/* SQL 智学 — Terminal Brutalism (refined v2)
   Design tokens & component styles, applied directly to native DOM
   produced by src/ui/*.js. No CSS framework. */

/* ──────────────────────────────────────────────────
   Design tokens
   ────────────────────────────────────────────────── */
:root {
  /* Surface */
  --bg:           #080808;
  --bg-panel:     #131313;
  --bg-panel-2:   #181818;
  --bg-input:     #0e0e0e;

  /* Borders */
  --br:           #1f1f1f;
  --br-strong:    #2a2a2a;
  --br-glow:      #3a3a3a;

  /* Text — WCAG AA against #080808 */
  --tx:           #e2e2e2;
  --tx-2:         #a3a3a3;
  --tx-3:         #6a6a6a;
  --tx-mute:      #404040;

  /* Accent — Catppuccin-inspired soft mint */
  --accent:       #a6e3a1;
  --accent-dim:   #4d6e4b;
  --accent-bg:    rgba(166, 227, 161, 0.07);
  --accent-glow:  rgba(166, 227, 161, 0.18);

  /* PASS reserved fluorescent */
  --pass:         #50fa7b;
  --pass-bg:      rgba(80, 250, 123, 0.10);
  --ok:           var(--pass);

  --warn:         #f9e2af;
  --warn-dim:     #6e6240;
  --warn-bg:      rgba(249, 226, 175, 0.08);

  --fail:         #f38ba8;
  --fail-bg:      rgba(243, 139, 168, 0.10);

  --info:         #89b4fa;
  --info-dim:     #4a6285;
  --info-bg:      rgba(137, 180, 250, 0.08);
  --info-glow:    rgba(137, 180, 250, 0.18);
  --magenta:      #cba6f7;

  /* Type scale — bumped +1px globally for Chinese legibility (Windows
     ClearType renders sub-12px CJK glyphs poorly). The previous scale
     was 10/11/12/13/14/18/20; this is 11/12/13/14/15/19/22. The names
     keep their semantics so per-element overrides still read clearly.
     --fs-2xl is reserved for hero numbers (report stat cards). */
  --fs-xxs:       11px;
  --fs-xs:        12px;
  --fs-sm:        13px;
  --fs-base:      14px;
  --fs-md:        15px;
  --fs-lg:        19px;
  --fs-xl:        22px;
  --fs-2xl:       28px;

  /* Spacing */
  --gap-xs:       8px;
  --gap-sm:       12px;
  --gap-md:       20px;
  --gap-lg:       28px;

  --r:            4px;

  --mono: "JetBrains Mono", "Noto Sans Mono", ui-monospace, "SF Mono", "Cascadia Mono", "Consolas", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", monospace;
}

/* ──────────────────────────────────────────────────
   Reset & base
   ────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { background: var(--bg); }
body {
  background:
    radial-gradient(circle at 12% -5%,  rgba(166,227,161,0.05), transparent 35%),
    radial-gradient(circle at 88% 105%, rgba(249,226,175,0.04), transparent 40%),
    var(--bg);
  background-attachment: fixed;
  color: var(--tx);
  font-family: var(--mono);
  font-size: var(--fs-base);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

[contenteditable], textarea, input { caret-color: var(--accent); }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: var(--br-strong); border-radius: 999px; }
::-webkit-scrollbar-thumb:hover { background: var(--br-glow); }
::-webkit-scrollbar-track { background: transparent; }

/* ──────────────────────────────────────────────────
   App shell — produced by src/main.js
   ────────────────────────────────────────────────── */
#app { min-height: 100vh; }

#app > header {
  position: sticky; top: 0; z-index: 20;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--br-strong);
  padding: 10px 24px;
  display: flex; align-items: center; gap: 24px;
  margin: 0;
}
#app > header h1 {
  margin: 0;
  font-size: var(--fs-base);
  font-weight: 600; color: var(--accent);
  letter-spacing: 0.02em;
  display: flex; align-items: center; gap: 8px;
}
#app > header h1::before {
  content: "▮";
  animation: blink 1.2s steps(1) infinite;
}
@keyframes blink { 50% { opacity: 0.3; } }

.app-nav { display: flex; gap: 0; flex: 1; }
.app-nav .btn {
  padding: 12px 20px;
  background: transparent; border: 0;
  color: var(--tx-3);
  font-family: var(--mono); font-size: var(--fs-sm); font-weight: 500;
  cursor: pointer;
  position: relative;
  transition: color 0.15s;
}
.app-nav .btn:hover { color: var(--tx); }
.app-nav .btn.btn-active { color: var(--accent); }
.app-nav .btn.btn-active::before {
  content: ''; position: absolute; left: 12px; right: 12px; bottom: -11px;
  height: 2px; background: var(--accent);
  box-shadow: 0 0 8px var(--accent-glow);
}

main.app-route {
  padding: var(--gap-md) var(--gap-lg);
  max-width: 1640px;
  margin: 0 auto;
}
@media (max-width: 1280px) {
  main.app-route { padding: var(--gap-md); }
}
@media (max-width: 1024px) {
  main.app-route { padding: var(--gap-sm); }
}

/* ──────────────────────────────────────────────────
   Panel — base for sections
   ────────────────────────────────────────────────── */
.panel {
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  position: relative;
  margin-bottom: var(--gap-md);
}
.panel::before {
  content: ''; position: absolute; left: 0; right: 0; top: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--br-glow), transparent);
}
.panel-body { padding: var(--gap-md); }

.ilabel {
  display: flex; align-items: baseline; gap: 8px;
  font-size: var(--fs-xs); color: var(--tx-3);
  margin-bottom: var(--gap-sm);
  text-transform: lowercase; letter-spacing: 0.04em;
}
.ilabel::before { content: "▸"; color: var(--accent-dim); }
.ilabel .meta { margin-left: auto; color: var(--tx-mute); }

/* ──────────────────────────────────────────────────
   Buttons
   ────────────────────────────────────────────────── */
.btn {
  background: transparent;
  border: 1px solid var(--br-strong);
  color: var(--tx);
  padding: 6px 14px;
  font-family: var(--mono); font-size: var(--fs-xs); font-weight: 500;
  cursor: pointer; border-radius: var(--r);
  transition: all 0.15s;
}
.btn:hover { border-color: var(--br-glow); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary {
  border-color: var(--accent-dim); color: var(--accent); background: var(--accent-bg);
}
.btn-primary:hover { background: var(--accent); color: var(--bg); border-color: var(--accent); }
.btn-danger:hover { border-color: var(--fail); color: var(--fail); }
.btn-ghost { border: 0; color: var(--tx-3); }
.btn-ghost:hover { color: var(--tx); }

/* ──────────────────────────────────────────────────
   Forms
   ────────────────────────────────────────────────── */
input[type="text"], input[type="url"], input[type="password"], textarea, select {
  font-family: var(--mono); font-size: var(--fs-base);
  background: var(--bg-input);
  border: 1px solid var(--br-strong);
  color: var(--tx);
  padding: 8px 12px;
  border-radius: var(--r);
  outline: none;
  width: 100%;
}
input:focus, textarea:focus, select:focus {
  border-color: var(--accent-dim);
  background: var(--bg);
}

label {
  display: block; margin-bottom: var(--gap-sm);
  font-size: var(--fs-sm); color: var(--tx-2);
}
label > span:first-child {
  display: block; font-size: var(--fs-xs);
  color: var(--tx-3); text-transform: lowercase;
  letter-spacing: 0.04em; margin-bottom: 4px;
}
label > span:first-child::before { content: "▸ "; color: var(--accent-dim); }

/* ──────────────────────────────────────────────────
   Practice view — superseded layout (kept here only as a marker;
   the live rules are at the bottom of this file).
   ────────────────────────────────────────────────── */

/* Theme picker */
.theme-picker { border: 0; padding: 0; margin: 0; }
.theme-picker legend { font-size: 0; height: 0; padding: 0; }
.theme-picker .theme-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 6px;
  margin-bottom: var(--gap-sm);
}
.theme-option {
  display: flex; align-items: center; gap: 6px;
  padding: 8px 10px;
  background: var(--bg-input); border: 1px solid var(--br-strong);
  border-radius: var(--r); cursor: pointer;
  font-size: var(--fs-sm); color: var(--tx-2);
  transition: all 0.15s;
}
.theme-option:hover { color: var(--tx); border-color: var(--br-glow); }
.theme-option input { display: none; }
.theme-option:has(input:checked) {
  color: var(--accent); border-color: var(--accent-dim); background: var(--accent-bg);
}
.theme-option:has(input:checked)::before { content: "× "; }
.theme-option:not(:has(input:checked))::before { content: "+ "; color: var(--tx-mute); }

.theme-custom textarea { min-height: 60px; resize: vertical; }

/* Difficulty buttons */
.difficulty-picker { border: 0; padding: 0; margin: 0; }
.difficulty-picker legend { font-size: 0; height: 0; padding: 0; }
.diff-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; }
.diff-btn {
  background: var(--bg-input); border: 1px solid var(--br-strong);
  color: var(--tx-2); padding: 8px 4px;
  font-family: var(--mono); font-size: var(--fs-sm); font-weight: 500;
  cursor: pointer; border-radius: var(--r);
  transition: all 0.15s;
  position: relative;
}
.diff-btn:hover { color: var(--tx); border-color: var(--br-glow); }
.diff-btn.active {
  color: var(--accent); border-color: var(--accent-dim); background: var(--accent-bg);
}
.diff-btn.active::before {
  content: ''; position: absolute; left: 8px; right: 8px; top: -1px;
  height: 2px; background: var(--accent); border-radius: 1px;
}

/* Topic chips */
.topic-chips { border: 0; padding: 0; margin: 0; }
.topic-chips legend { font-size: 0; height: 0; padding: 0; }
.topic-chips-list { display: flex; flex-wrap: wrap; gap: 4px; }
/* .chip / .chip-selected definition lives further down (search "chip pill")
   — keeping a single source of truth avoids the L283/L1834 split that
   used to leave stale ::before prefixes from a removed older design. */

/* Schema panel */
.schema-panel h3 { font-size: 0; height: 0; padding: 0; margin: 0; }
.schema-empty {
  padding: var(--gap-md); color: var(--tx-3);
  background: var(--bg-input); border: 1px dashed var(--br);
  border-radius: var(--r); text-align: center;
  font-size: var(--fs-sm);
}
.schema-table {
  margin-bottom: var(--gap-sm);
  border: 1px solid var(--br); border-radius: var(--r);
  overflow: hidden;
  background: var(--bg-input);
}
.schema-table h4 {
  margin: 0; padding: 8px 12px;
  background: var(--bg-panel-2); border-bottom: 1px solid var(--br);
  font-size: var(--fs-sm); font-weight: 500;
  color: var(--accent);
}
.schema-table h4::before { content: "▸ "; color: var(--accent-dim); }
.schema-cols {
  width: 100%; border-collapse: collapse;
  font-size: var(--fs-xs); margin: 0;
}
.schema-cols th {
  text-align: left; padding: 6px 12px;
  color: var(--tx-3); background: transparent;
  font-weight: 500; text-transform: lowercase;
  letter-spacing: 0.04em;
  border-bottom: 1px solid var(--br);
}
.schema-cols td {
  padding: 4px 12px; color: var(--tx-2);
  border: 0;
}
.schema-cols tr:last-child td { padding-bottom: 8px; }
.schema-pk { padding: 6px 12px; margin: 0; font-size: var(--fs-xs); color: var(--accent); }
.schema-fk { padding: 4px 12px 8px; margin: 0; font-size: var(--fs-xs); color: var(--magenta); list-style: none; }
.schema-fk li { padding: 2px 0; }
.schema-fk li::before { content: "↗ "; color: var(--magenta); }

/* ──────────────────────────────────────────────────
   Editor — legacy textarea path (kept for non-highlighted use cases).
   The active editor is the highlighted mirror (.sql-editor-wrap) defined
   below; rules here intentionally narrow their selector with
   `:not(.sql-editor-textarea)` so they never override the mirror.
   ────────────────────────────────────────────────── */
.editor-view { padding: 0; }
textarea.sql-editor:not(.sql-editor-textarea),
textarea[data-sql-editor]:not(.sql-editor-textarea) {
  font-family: var(--mono);
  font-size: var(--fs-md);
  line-height: 1.7;
  padding: 16px 20px;
  background: var(--bg-input);
  color: var(--tx);
  min-height: 160px;
  border: 1px solid var(--br);
  border-radius: var(--r);
  outline: none;
  resize: vertical;
  tab-size: 2;
}
textarea.sql-editor:not(.sql-editor-textarea):focus {
  background: #0a0a0a;
  border-color: var(--accent-dim);
}

.editor-actions {
  display: flex; gap: 8px; margin-top: var(--gap-sm); flex-wrap: wrap; align-items: center;
}

/* Dual editor for set_vs_join_compare */
.dual-editor-view .dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap-md);
}
@media (max-width: 900px) {
  .dual-editor-view .dual-grid { grid-template-columns: 1fr; }
}
.dual-pane h4 {
  margin: 0 0 8px; padding: 0;
  font-size: var(--fs-xs); color: var(--tx-3);
  text-transform: lowercase; letter-spacing: 0.04em;
  font-weight: 500;
}
.dual-pane h4::before { content: "▸ "; color: var(--accent-dim); }

/* ──────────────────────────────────────────────────
   Verdict
   ────────────────────────────────────────────────── */
.verdict {
  margin-bottom: var(--gap-md);
  display: flex; align-items: stretch; min-height: 56px;
  border: 1px solid;
  border-radius: var(--r); overflow: hidden;
  font-size: var(--fs-base);
  background: transparent !important;
  color: inherit !important;
}
.verdict::before {
  content: ''; width: 4px; flex-shrink: 0;
  background: currentColor;
}
.verdict::after {
  content: attr(data-tag);
  padding: 0 14px;
  display: grid; place-items: center;
  font-weight: 700; letter-spacing: 0.05em;
  flex-shrink: 0;
}
.verdict-correct {
  border-color: var(--pass) !important;
  background: var(--pass-bg) !important;
  color: var(--pass) !important;
}
.verdict-correct::after { content: "PASS"; }
.verdict-wrong {
  border-color: var(--fail) !important;
  background: var(--fail-bg) !important;
  color: var(--fail) !important;
}
.verdict-wrong::after { content: "FAIL"; }
.verdict > * {
  padding: 14px 16px;
  font-style: normal !important;
  display: flex; align-items: center; gap: 8px;
  flex: 1;
  color: inherit !important;
}
.verdict-diff { color: inherit; opacity: 0.85; font-size: var(--fs-xs); }

.sandbox-error {
  padding: 12px 16px !important; color: var(--fail) !important;
  background: var(--fail-bg); border: 1px solid var(--fail);
  border-radius: var(--r); margin-bottom: var(--gap-md);
}

.truncation-banner {
  padding: 8px 14px !important;
  background: var(--warn-bg) !important; color: var(--warn) !important;
  border: 1px solid var(--warn-dim);
  border-radius: var(--r);
  font-size: var(--fs-xs);
  margin-bottom: var(--gap-sm);
}

/* ──────────────────────────────────────────────────
   Result table
   ────────────────────────────────────────────────── */
table.result-table, table[data-result-table] {
  width: 100%; border-collapse: collapse;
  font-family: var(--mono); font-size: var(--fs-sm);
  background: var(--bg-panel);
  border: 1px solid var(--br); border-radius: var(--r);
  overflow: hidden;
}
.result-table th {
  text-align: left; padding: 8px 14px;
  background: var(--bg-input); color: var(--info);
  font-weight: 500; font-size: var(--fs-xs);
  text-transform: lowercase; letter-spacing: 0.04em;
  border-bottom: 1px solid var(--br-strong);
}
.result-table td {
  padding: 8px 14px; color: var(--tx);
  border-bottom: 1px solid var(--br);
}
.result-table tr:last-child td { border-bottom: 0; }
.result-table tr:hover td { background: var(--bg-input); }

/* Compact result verdict bar */
.result-empty {
  color: var(--tx-3);
  font-size: var(--fs-sm);
  font-style: italic;
  padding: 12px;
  text-align: center;
}
.result-verdict {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  border-radius: var(--r);
  font-size: var(--fs-sm);
}
.result-verdict-ok {
  background: var(--pass-bg);
  border: 1px solid var(--pass);
  color: var(--pass);
}
.result-verdict-fail {
  background: var(--fail-bg);
  border: 1px solid var(--fail);
  color: var(--fail);
}
.result-verdict-icon {
  font-size: var(--fs-lg);
  font-weight: 700;
  line-height: 1;
}
.result-verdict-label {
  font-weight: 600;
}
.result-verdict-detail {
  font-size: var(--fs-xs);
  opacity: 0.85;
}
.result-show-btn {
  margin-top: 8px;
  font-size: var(--fs-xs);
  padding: 4px 14px;
  background: transparent;
  border: 1px solid var(--br-strong);
  color: var(--tx-2);
  border-radius: 3px;
  cursor: pointer;
  transition: all 120ms ease;
}
.result-show-btn:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
}

/* Result modal */
.result-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1200;
  /* The dialog host (.app-dialog) has pointer-events:none so the empty
     overlay never eats clicks under it. Each modal MUST re-enable
     pointer-events on its own backdrop, otherwise the dismiss-on-outside
     click and any inner buttons stop working. (See quota-dialog for the
     same pattern.) */
  pointer-events: auto;
}
.result-modal-card {
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  width: 720px;
  max-width: 92vw;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 16px 48px rgba(0,0,0,0.6);
}
.result-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--br);
  flex-shrink: 0;
}
.result-modal-header h3 {
  margin: 0;
  font-size: var(--fs-lg);
  color: var(--tx);
}
.result-modal-content {
  overflow: auto;
  padding: 12px;
  flex: 1;
  min-height: 0;
}
.result-modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  padding: 12px 16px;
  border-top: 1px solid var(--br);
  flex-shrink: 0;
}
.result-modal-truncation {
  padding: 6px 12px;
  background: var(--warn-bg);
  color: var(--warn);
  border: 1px solid var(--warn-dim);
  border-radius: var(--r);
  font-size: var(--fs-xs);
  margin-bottom: 8px;
}

/* Comparison layout */
.result-modal-verdict {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  border-radius: var(--r);
  font-size: var(--fs-sm);
  font-weight: 600;
  margin-bottom: 12px;
}
.result-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
@media (max-width: 700px) {
  .result-comparison { grid-template-columns: 1fr; }
}
.result-compare-section {
  min-width: 0;
  overflow: auto;
}
.result-compare-title {
  margin: 0 0 6px;
  font-size: var(--fs-sm);
  font-weight: 600;
  padding: 4px 8px;
  border-radius: 3px;
}
.result-compare-user {
  color: var(--info);
  background: rgba(137, 180, 250, 0.08);
}
.result-compare-expected {
  color: var(--pass);
  background: rgba(80, 250, 123, 0.08);
}
.result-compare-empty {
  color: var(--tx-3);
  font-style: italic;
  font-size: var(--fs-sm);
  padding: 8px;
}
.result-modal-error {
  color: var(--fail);
  padding: 12px;
  background: var(--fail-bg);
  border: 1px solid var(--fail);
  border-radius: var(--r);
  font-size: var(--fs-sm);
}

/* ──────────────────────────────────────────────────
   Tutor — sticky right column
   ────────────────────────────────────────────────── */
.tutor-view {
  position: sticky; top: 64px;
  max-height: calc(100vh - 80px);
  display: flex; flex-direction: column;
  background: var(--bg-panel);
  border: 1px solid var(--br); border-radius: var(--r);
  padding: var(--gap-md);
}
.tutor-view::before {
  content: ''; position: absolute; left: 0; right: 0; top: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--br-glow), transparent);
}
/* (Legacy .tutor-view h3 styling removed — the tutor view now uses
   .tutor-header with .tutor-role-chip + .tutor-new-btn instead.) */

.tutor-thread {
  display: flex; flex-direction: column; gap: 14px;
  flex: 1; min-height: 0;
  overflow-y: auto;
  list-style: none;
  margin: 0;
  padding: 4px 0;
}
.tutor-msg {
  display: grid; grid-template-columns: 28px 1fr; gap: 10px;
  align-items: flex-start; font-size: var(--fs-base);
}
.tutor-msg::before {
  width: 28px; height: 28px;
  display: grid; place-items: center;
  font-family: var(--mono); font-size: var(--fs-xs); font-weight: 700;
  border: 1px solid currentColor; border-radius: var(--r);
}
.tutor-msg[data-role="assistant"] { color: var(--accent); }
.tutor-msg[data-role="user"] { color: var(--warn); }
.tutor-msg[data-role="assistant"]::before { content: ">_"; }
.tutor-msg[data-role="user"]::before { content: "$_"; }
.tutor-content {
  padding: 10px 14px;
  background: var(--bg-input); border: 1px solid var(--br);
  border-radius: var(--r);
  line-height: 1.65;
  color: var(--tx);
}
.tutor-msg[data-role="user"] .tutor-content {
  border-color: var(--warn-dim); background: var(--warn-bg);
}
.tutor-pending {
  font-size: var(--fs-xs); color: var(--tx-3);
  padding: 4px 0 0 38px;
  display: flex; align-items: center; gap: 4px;
}
.tutor-pending::before {
  content: "● ● ●";
  letter-spacing: 4px; color: var(--accent);
  animation: bob 1.2s ease-in-out infinite;
}
@keyframes bob {
  0%, 60%, 100% { opacity: 0.4; }
  30% { opacity: 1; }
}

.tutor-composer-row {
  margin-top: var(--gap-sm);
  display: grid; grid-template-columns: 1fr auto; gap: 8px;
}
.tutor-composer {
  background: var(--bg-input);
  border: 1px solid var(--br-strong);
  color: var(--tx);
  padding: 8px 12px;
  font-family: var(--mono); font-size: var(--fs-base);
  border-radius: var(--r);
  resize: vertical; min-height: 48px; max-height: 200px;
}
.tutor-composer:focus { border-color: var(--accent-dim); outline: none; }
.tutor-refsql {
  margin-top: var(--gap-sm);
  padding: 12px;
  background: var(--bg-input); border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono); font-size: var(--fs-sm);
  color: var(--accent);
  white-space: pre-wrap; overflow-x: auto;
}

/* ──────────────────────────────────────────────────
   Settings view
   ────────────────────────────────────────────────── */
.settings-form {
  max-width: 720px;
}
.settings-form h2 {
  font-size: var(--fs-lg); font-weight: 600;
  color: var(--accent); margin: 0 0 var(--gap-md);
}
.settings-form h2::before { content: "❯ "; color: var(--accent-dim); }
.settings-cors-notice {
  padding: 12px 16px;
  background: var(--bg-input); border: 1px solid var(--br);
  border-left: 3px solid var(--warn);
  border-radius: var(--r);
  font-size: var(--fs-sm); color: var(--tx-2);
  margin-bottom: var(--gap-md); line-height: 1.7;
}
.settings-field { margin-bottom: var(--gap-md); }
.settings-key-row { display: grid; grid-template-columns: 1fr auto; gap: 8px; }
.settings-key-mask {
  display: block; margin-top: 6px;
  font-family: var(--mono); font-size: var(--fs-xs); color: var(--tx-3);
}
.settings-actions { display: flex; gap: 8px; margin-top: var(--gap-md); }
.settings-status {
  margin-top: var(--gap-md); padding: 10px 14px;
  background: var(--bg-input); border: 1px solid var(--br);
  border-radius: var(--r); font-size: var(--fs-sm); color: var(--tx-2);
}

/* ──────────────────────────────────────────────────
   History view
   ────────────────────────────────────────────────── */
.history-header {
  display: flex; align-items: center; gap: var(--gap-sm);
  margin-bottom: var(--gap-md);
}
.history-header h2 {
  margin: 0; font-size: var(--fs-lg); font-weight: 600;
  color: var(--accent);
}
.history-header h2::before { content: "❯ "; color: var(--accent-dim); }
.history-filter {
  display: flex; align-items: center; gap: 6px;
  font-size: var(--fs-sm); color: var(--tx-2);
  cursor: pointer; user-select: none;
  padding: 6px 12px;
  border: 1px solid var(--br-strong); border-radius: var(--r);
}
.history-filter:has(input:checked) {
  color: var(--warn); border-color: var(--warn-dim); background: var(--warn-bg);
}

.history-list {
  list-style: none; padding: 0; margin: 0;
  display: flex; flex-direction: column; gap: 8px;
}
.history-item {
  padding: 12px 16px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  display: grid; grid-template-columns: 4px 1fr; gap: 12px;
  align-items: stretch;
  position: relative;
}
.history-item::before {
  content: ''; background: var(--tx-mute);
  border-radius: 2px;
}
.history-item[data-history-correct="true"]::before { background: var(--pass); }
.history-item[data-history-correct="false"]::before { background: var(--fail); }
.history-item > .history-meta,
.history-item > .history-sql {
  grid-column: 2;
}
.history-meta {
  font-size: var(--fs-xs); color: var(--tx-3);
  margin-bottom: 6px;
  display: flex; gap: 8px;
}
.history-meta time { color: var(--tx-2); }
.history-verdict { font-weight: 600; }
.history-item[data-history-correct="true"] .history-verdict { color: var(--pass); }
.history-item[data-history-correct="false"] .history-verdict { color: var(--fail); }
.history-sql {
  margin: 0; padding: 8px 12px;
  background: var(--bg-input); border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono); font-size: var(--fs-sm);
  color: var(--tx);
  white-space: pre-wrap; overflow-x: auto;
}

.history-empty {
  padding: 48px; text-align: center;
  color: var(--tx-3);
  background: var(--bg-panel);
  border: 1px dashed var(--br);
  border-radius: var(--r);
  font-size: var(--fs-sm);
}

/* ──────────────────────────────────────────────────
   Report view (R16) — multi-section ability report.
   Built around three visual primitives:
     • SVG bar rows (.bar-row)
     • Stat cards (.stat-card) for the overview hero
     • AI score cards (.score-card) for the multi-dimensional grid
   The whole .report-body is the snapshot target for PDF export, so
   keep it self-contained (no dependency on parent CSS).
   ────────────────────────────────────────────────── */

.report-view {
  display: flex;
  flex-direction: column;
  gap: var(--gap-md);
}
.report-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gap-sm);
  flex-wrap: wrap;
}
.report-title {
  margin: 0;
  font-size: var(--fs-lg);
  font-weight: 600;
  color: var(--accent);
}
.report-title::before { content: "❯ "; color: var(--accent-dim); }
.report-actions {
  display: flex; gap: 8px; flex-wrap: wrap;
}

.report-empty {
  padding: 32px; text-align: center;
  color: var(--tx-3); font-size: var(--fs-sm);
  background: var(--bg-panel); border: 1px dashed var(--br);
  border-radius: var(--r);
}
.report-empty-mini {
  color: var(--tx-3); font-size: var(--fs-sm); margin: 8px 0; font-style: italic;
}

/* ── Body container — the PDF snapshot target. ── */
.report-body {
  display: flex;
  flex-direction: column;
  gap: var(--gap-md);
  padding: var(--gap-md);
  background: var(--bg-panel); border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono);
  font-size: var(--fs-sm);
  color: var(--tx);
  line-height: 1.7;
}

/* ── Section frames ── */
.report-section {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px 18px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
}
.report-section-title {
  margin: 0;
  font-size: var(--fs-md);
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.02em;
  display: flex; align-items: center; gap: 8px;
}
.report-section-title::before { content: "◆"; color: var(--accent-dim); font-size: var(--fs-xs); }
.report-section-tag {
  font-size: var(--fs-xs);
  font-weight: 500;
  padding: 1px 7px;
  background: var(--magenta);
  color: var(--bg);
  border-radius: 999px;
  letter-spacing: 0.04em;
}
.report-section-reco { border-left: 3px solid var(--magenta); }
.report-section-noai { border-left: 3px solid var(--warn-dim); }

/* ── Overview hero cards ── */
.report-overview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 10px;
}
.stat-card {
  display: flex; flex-direction: column;
  padding: 10px 14px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
}
.stat-label {
  font-size: var(--fs-xs);
  color: var(--tx-3);
  letter-spacing: 0.04em;
  text-transform: lowercase;
}
.stat-big-row {
  display: flex; align-items: baseline; gap: 4px;
  margin-top: 4px;
}
.stat-big {
  font-size: var(--fs-2xl);
  font-weight: 700;
  color: var(--accent);
  font-family: var(--mono);
  letter-spacing: -0.01em;
}
.stat-unit {
  font-size: var(--fs-xs);
  color: var(--tx-3);
}
.report-summary {
  margin: 0;
  padding: 10px 14px;
  background: var(--bg-panel);
  border-left: 3px solid var(--accent);
  border-radius: 3px;
  color: var(--tx-2);
  font-size: var(--fs-sm);
  line-height: 1.7;
  font-style: italic;
}

/* ── Bar rows (difficulty / topic mastery) ── */
.report-bar-list {
  display: flex; flex-direction: column; gap: 8px;
}
.bar-row {
  display: grid;
  grid-template-columns: minmax(120px, 1.2fr) minmax(0, 3fr) minmax(110px, auto);
  align-items: center;
  gap: 12px;
}
.bar-label {
  display: flex; flex-direction: column; min-width: 0;
}
.bar-label-text {
  font-size: var(--fs-sm);
  color: var(--tx);
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.bar-label-meta {
  font-size: var(--fs-xxs);
  color: var(--tx-3);
  letter-spacing: 0.04em;
  text-transform: lowercase;
}
.bar-svg {
  width: 100%;
  height: 14px;
  display: block;
  overflow: visible;
}
.bar-track { fill: var(--bg); }
.bar-fill-pass { fill: var(--pass); }
.bar-fill-warn { fill: var(--warn); }
.bar-fill-fail { fill: var(--fail); }
.bar-fill-mute { fill: var(--tx-mute); }
.bar-ratio {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  font-variant-numeric: tabular-nums;
  text-align: right;
  white-space: nowrap;
}
.bar-ratio-pass { color: var(--pass); }
.bar-ratio-warn { color: var(--warn); }
.bar-ratio-fail { color: var(--fail); }
.bar-ratio-mute { color: var(--tx-3); }

.rate-badge {
  display: inline-block;
  padding: 1px 8px;
  font-size: var(--fs-xs);
  font-weight: 600;
  border-radius: 999px;
  margin-left: 6px;
}
.rate-badge-pass { color: var(--pass); border: 1px solid var(--pass); background: var(--pass-bg); }
.rate-badge-warn { color: var(--warn); border: 1px solid var(--warn-dim); background: var(--warn-bg); }
.rate-badge-fail { color: var(--fail); border: 1px solid var(--fail); background: var(--fail-bg); }

/* ── AI multi-dimensional score cards ── */
.report-score-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}
.score-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 12px 14px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-left-width: 3px;
  border-radius: var(--r);
}
.score-card-pass { border-left-color: var(--pass); }
.score-card-warn { border-left-color: var(--warn); }
.score-card-fail { border-left-color: var(--fail); }
.score-card-head {
  display: flex; align-items: baseline; justify-content: space-between; gap: 8px;
}
.score-card-name {
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--tx);
}
.score-card-num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--fs-md);
  color: var(--accent);
}
.score-card-num strong { font-size: var(--fs-lg); }
.score-card-max { color: var(--tx-3); font-size: var(--fs-xs); }
.score-card-bar-track {
  width: 100%;
  height: 6px;
  background: var(--bg-input);
  border-radius: 1px;
  overflow: hidden;
}
.score-card-bar { height: 100%; transition: width 280ms ease; }
.score-card-bar-pass { background: var(--pass); }
.score-card-bar-warn { background: var(--warn); }
.score-card-bar-fail { background: var(--fail); }
.score-card-comment {
  margin: 0;
  font-size: var(--fs-xs);
  color: var(--tx-2);
  line-height: 1.5;
}

/* ── Weak topics list ── */
.weak-topic-list {
  list-style: none; margin: 0; padding: 0;
  display: flex; flex-direction: column; gap: 10px;
}
.weak-topic-item {
  padding: 10px 12px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-left: 3px solid var(--fail);
  border-radius: var(--r);
}
.weak-topic-head {
  display: flex; align-items: center; gap: 10px;
  margin-bottom: 4px;
}
.weak-topic-rank {
  font-family: var(--mono);
  font-weight: 700;
  color: var(--fail);
  font-size: var(--fs-sm);
}
.weak-topic-name { font-weight: 600; flex: 1; }
.weak-topic-rate {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--fs-sm);
  color: var(--fail);
  font-weight: 600;
}
.weak-topic-advice {
  margin: 0;
  font-size: var(--fs-sm);
  color: var(--tx-2);
  line-height: 1.6;
  padding-left: 4px;
}

.report-recommendation {
  margin: 0;
  padding: 12px 14px;
  background: var(--bg-panel);
  border: 1px solid var(--magenta);
  border-radius: var(--r);
  color: var(--tx);
  font-size: var(--fs-sm);
  line-height: 1.75;
  white-space: pre-wrap;
}

.report-raw-md {
  margin: 8px 0 0;
  padding: 10px 12px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono);
  font-size: var(--fs-sm);
  color: var(--tx-2);
  white-space: pre-wrap;
  max-height: 320px;
  overflow: auto;
}

/* ── Print / PDF stylesheet ── */
@media print {
  /* Hide app chrome — we only want the report. */
  body { background: white; color: #111; }
  #app > header, .app-nav, .app-dialog, .app-toast,
  .report-toolbar, .storage-fallback-banner { display: none !important; }
  main.app-route { padding: 0; max-width: 100%; }
  .report-view { gap: 8px; }
  .report-body {
    background: white;
    border: 0;
    color: #111;
    padding: 0;
  }
  .report-section {
    background: #f7f8f6;
    border-color: #d8dad4;
    page-break-inside: avoid;
    color: #111;
  }
  .report-section-title { color: #2a6e3a; }
  .stat-card, .score-card, .weak-topic-item, .report-recommendation,
  .report-summary, .report-raw-md {
    background: white;
    border-color: #d8dad4;
    color: #111;
  }
  .stat-big, .score-card-num { color: #2a6e3a; }
  .bar-track { fill: #e7e8e3; }
  .bar-label-text, .stat-label, .bar-label-meta, .stat-unit,
  .score-card-comment, .weak-topic-advice { color: #333; }
  .bar-ratio-pass, .rate-badge-pass, .score-card-bar-pass { color: #1f7a35; }
  .bar-ratio-warn, .rate-badge-warn, .score-card-bar-warn { color: #8a6a00; }
  .bar-ratio-fail, .rate-badge-fail, .score-card-bar-fail,
  .weak-topic-rank, .weak-topic-rate { color: #b3304a; }
}

/* ──────────────────────────────────────────────────
   Quota dialog (R15.6 / Property 12)
   Selectors data-quota-dialog / data-quota-export are protected by tests.
   ────────────────────────────────────────────────── */
.app-dialog { position: fixed; inset: 0; pointer-events: none; z-index: 1500; }
.quota-dialog {
  position: fixed; top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  background: var(--bg-panel);
  padding: 24px;
  border: 1px solid var(--accent-dim); border-radius: var(--r);
  box-shadow: 0 16px 48px rgba(0,0,0,0.6);
  pointer-events: auto;
  max-width: 480px; width: 90%;
}
.quota-dialog h3 {
  margin: 0 0 var(--gap-sm);
  font-size: var(--fs-lg); color: var(--warn);
}
.quota-dialog h3::before { content: "⚠ "; }
.quota-dialog p { color: var(--tx-2); font-size: var(--fs-base); margin: 0 0 var(--gap-md); }

/* ──────────────────────────────────────────────────
   Error toast (R14.6)
   ────────────────────────────────────────────────── */
.app-toast {
  position: fixed; top: 70px; right: 16px; z-index: 1000;
  max-width: 360px;
}
.error-toast, [data-error-toast] {
  background: var(--bg-panel);
  color: var(--fail);
  border: 1px solid var(--fail);
  border-radius: var(--r);
  padding: 12px 16px;
  margin-bottom: var(--gap-sm);
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
  font-size: var(--fs-sm);
  display: flex; align-items: flex-start; gap: 12px;
}
.error-toast-text { flex: 1; }

/* ──────────────────────────────────────────────────
   Storage fallback banner (R2.5)
   ────────────────────────────────────────────────── */
.storage-fallback-banner {
  position: sticky; top: 0; z-index: 50;
  padding: 8px 16px !important;
  background: var(--warn-bg) !important; color: var(--warn) !important;
  border-bottom: 1px solid var(--warn-dim);
  font-size: var(--fs-xs) !important;
  text-align: center;
}

/* ──────────────────────────────────────────────────
   Progress dialog (agent step-by-step status)
   Surfaces SchemaGen / QuestionGen retry attempts so users see exactly
   which validation step failed instead of a generic "格式异常" toast.
   ────────────────────────────────────────────────── */
.progress-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1100;
  pointer-events: auto;
}
.progress-card {
  background: var(--bg-panel);
  border: 1px solid var(--accent-dim);
  border-radius: var(--r);
  padding: 20px 24px;
  width: 540px;
  max-width: 92vw;
  max-height: 80vh;
  overflow: auto;
  box-shadow: 0 16px 48px rgba(0,0,0,0.6);
}
.progress-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--accent-dim);
}
.progress-title {
  font-size: var(--fs-lg);
  color: var(--accent);
  font-weight: 600;
}
.progress-steps {
  list-style: none; margin: 0; padding: 0;
  display: flex; flex-direction: column; gap: 8px;
}
.progress-step {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 10px 12px;
  border: 1px solid var(--accent-dim);
  border-radius: 6px;
  background: var(--bg-input);
  transition: border-color 120ms ease, background 120ms ease;
}
.progress-glyph {
  font-family: var(--mono);
  font-size: var(--fs-base);
  width: 1em; flex-shrink: 0;
  text-align: center;
}
.progress-step-body { flex: 1; min-width: 0; }
.progress-step-label {
  font-size: var(--fs-base);
  color: var(--tx);
}
.progress-step-detail {
  font-size: var(--fs-xs);
  color: var(--tx-3);
  margin-top: 4px;
  word-break: break-word;
  white-space: pre-wrap;
}
.progress-step-pending .progress-glyph { color: var(--tx-3); }
.progress-step-running { border-color: var(--accent); }
.progress-step-running .progress-glyph {
  color: var(--accent);
  animation: progress-pulse 1.4s ease-in-out infinite;
}
.progress-step-ok      { border-color: var(--ok, #5dc36d); }
.progress-step-ok .progress-glyph { color: var(--ok, #5dc36d); }
.progress-step-fail    { border-color: var(--fail, #e25a5a); }
.progress-step-fail .progress-glyph { color: var(--fail, #e25a5a); }
.progress-step-fail .progress-step-detail { color: var(--fail, #e25a5a); }

@keyframes progress-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.35; }
}

.progress-final {
  margin-top: 16px;
  padding: 10px 12px;
  border-radius: 6px;
  font-size: var(--fs-sm);
  white-space: pre-wrap;
  word-break: break-word;
}
.progress-final-done {
  background: rgba(93, 195, 109, 0.12);
  color: var(--ok, #5dc36d);
  border: 1px solid var(--ok, #5dc36d);
}
.progress-final-error {
  background: rgba(226, 90, 90, 0.12);
  color: var(--fail, #e25a5a);
  border: 1px solid var(--fail, #e25a5a);
}

/* Recovery action buttons rendered under .progress-final on error.
   Right-aligned, wrap on narrow viewports, sit inside the dialog card. */
.progress-actions {
  display: flex;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}
.progress-actions .btn {
  white-space: nowrap;
}


/* ──────────────────────────────────────────────────
   Practice — three-column full-viewport layout
   The page fills `100vh - <header>` and uses a CSS grid with two
   draggable splitter columns. Inside each column, the panels form a
   flex chain so the editor / result / tutor bodies inherit the full
   available height (no scroll-island).
   ────────────────────────────────────────────────── */
:root {
  /* Header is sticky at the top of #app. Keep this in sync with the actual
     padded nav height so fixed-height practice views do not spill vertically. */
  --app-header-h: 64px;
  /* Default column widths — practice-view writes these inline as well,
     overriding the defaults below if a saved layout is present. */
  --col-side: 300px;
  --col-tutor: 380px;
  /* Default in-column row heights (top row); the bottom row of each
     column is `1fr` so it fills whatever's left. practice-view rewrites
     these inline from the persisted layout when present. The editor
     row gets a generous default so the SQL textarea has room to breathe;
     users can still drag the splitter to override. */
  --row-question: 220px;
  --row-editor: 520px;
}

main.app-route:has(> .practice-view) {
  /* Practice owns its vertical gutters and fills the viewport. */
  max-width: 1900px;
  padding: 0;
}

.practice-view {
  display: grid;
  grid-template-columns:
    var(--col-side, 300px)
    8px
    minmax(0, 1fr)
    8px
    var(--col-tutor, 380px);
  gap: 0;
  align-items: stretch;
  height: calc(100vh - var(--app-header-h));
  min-height: 480px;
  padding: var(--gap-sm) 0;
}

/* Each column lays out its panels. Side + main use grid so a horizontal
   splitter can drag the top row's height; tutor stays a flex column
   because it only contains a single panel. */
.practice-side {
  display: grid;
  grid-template-rows: var(--row-question, 240px) 8px minmax(0, 1fr);
  gap: 0;
  min-height: 0;
  min-width: 0;
  padding: 0 4px;
}
.practice-main {
  display: grid;
  grid-template-rows: var(--row-editor, 360px) 8px minmax(0, 1fr);
  gap: 0;
  min-height: 0;
  min-width: 0;
  padding: 0;
}
.practice-tutor {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 0;
  min-width: 0;
  padding: 0 4px;
}
.practice-side  { padding-left: var(--gap-sm); padding-right: 0; }
.practice-tutor { padding-left: 0; padding-right: var(--gap-sm); }

/* Grid children: each panel must clamp to its assigned row so the
   splitter delta is honoured (without min-height:0 a tall body would
   force its row to grow regardless of the row track size). */
.practice-side  > .pf,
.practice-main  > .pf { min-height: 0; overflow: hidden; }

/* Tutor column fills its column. */
.practice-tutor > .pf { flex: 1 1 0; min-height: 0; }

/* Re-enable scrolling inside fully-stretched panel bodies, and remove
   the per-panel native resize handle — the column splitters cover the
   resize need now. */
.practice-side .pf-body,
.practice-main .pf-body,
.practice-tutor .pf-body {
  resize: none;
  overflow: auto;
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  max-height: none;
}

/* Splitter — vertical bar between columns. */
.splitter {
  user-select: none;
  background: transparent;
  position: relative;
  flex-shrink: 0;
}
.splitter-v {
  width: 8px;
  cursor: col-resize;
  align-self: stretch;
  display: flex;
  align-items: center;
  justify-content: center;
}
.splitter-v::before {
  content: "";
  width: 2px;
  height: 40px;
  background: var(--br-strong);
  border-radius: 1px;
  transition: background 120ms ease, height 120ms ease;
}
.splitter-v:hover::before,
.splitter-v.splitter-dragging::before {
  background: var(--accent);
  height: 60px;
}

/* Horizontal splitter — sits between two stacked panels in a column. */
.splitter-h {
  height: 8px;
  cursor: row-resize;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
}
.splitter-h::before {
  content: "";
  height: 2px;
  width: 40px;
  background: var(--br-strong);
  border-radius: 1px;
  transition: background 120ms ease, width 120ms ease;
}
.splitter-h:hover::before,
.splitter-h.splitter-dragging::before {
  background: var(--accent);
  width: 60px;
}

@media (max-width: 1024px) {
  .practice-view {
    grid-template-columns: 1fr;
    height: auto;
    gap: var(--gap-sm);
    padding: var(--gap-sm);
  }
  .practice-side, .practice-main, .practice-tutor {
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: var(--gap-sm);
    grid-template-rows: none;
  }
  .splitter-v, .splitter-h { display: none; }
  .practice-side  > .pf:first-child { flex: 0 0 auto; min-height: 200px; }
  .practice-side  > .pf:last-child  { flex: 0 0 auto; min-height: 280px; }
  .practice-main > .pf:first-child  { flex: 0 0 auto; min-height: 360px; }
  .practice-main > .pf:last-child   { flex: 0 0 auto; min-height: 200px; }
  .practice-tutor > .pf             { flex: 0 0 auto; min-height: 360px; }
}

/* Editor: make the wrap fill the panel body so the textarea grows. */
.practice-main .editor-view {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}
.practice-main .editor-view > .sql-editor-host {
  flex: 1;
  min-height: 0;
  display: flex;
}
.practice-main .editor-view > .sql-editor-host > .sql-editor-wrap {
  flex: 1;
  min-height: 0;
  resize: none;
}
.practice-main .editor-actions { flex: 0 0 auto; }

/* Result panel content fills its body, but result-table / verdict are
   intrinsically sized — push them to the top and let the body scroll. */
.practice-main .result-mount,
.practice-main [data-result-mount] {
  flex: 1;
  min-height: 0;
  overflow: auto;
}

/* Tutor: full-height chat with composer pinned at the bottom. */
.practice-tutor .tutor-view {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  position: static;     /* override the legacy sticky rule */
  max-height: none;
  padding: 0;
  border: 0;
  background: transparent;
}
.practice-tutor .tutor-thread {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
}
.practice-tutor .tutor-composer-row { flex: 0 0 auto; }
.practice-tutor .tutor-ref-card     { flex: 0 0 auto; }

/* Tutor header — new conversation button + AI 助手 role chip */
.tutor-header {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0 6px;
}
.tutor-role-chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 10px;
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--accent);
  border: 1px solid var(--accent-dim);
  border-radius: 999px;
  background: var(--accent-bg);
  user-select: none;
}
.tutor-role-chip::before {
  content: "◉";
  color: var(--accent);
  font-size: 8px;
  animation: tutor-pulse 2.4s ease-in-out infinite;
}
@keyframes tutor-pulse {
  0%, 100% { opacity: 0.55; }
  50% { opacity: 1; }
}
.tutor-header .tutor-new-btn {
  margin-left: auto;
}
.tutor-new-btn {
  font-size: var(--fs-xs);
  padding: 3px 10px;
  background: transparent;
  border: 1px solid var(--br-strong);
  color: var(--tx-2);
  border-radius: 3px;
  cursor: pointer;
  transition: all 120ms ease;
}
.tutor-new-btn:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
}

/* ─── Tutor (在线问答) keeps the mint accent but earns a clear role
   identity through chrome shape (role chip + softer bubbles) rather
   than a left-edge accent stripe. ─── */
.practice-tutor > .pf > .pf-header {
  background: linear-gradient(90deg, var(--accent-bg) 0%, var(--bg-panel-2) 60%);
}
.practice-tutor .tutor-msg[data-role="assistant"] .tutor-content {
  border-radius: 10px;
  padding: 12px 16px;
  line-height: 1.7;
}

/* Quick action chips */
.tutor-chips {
  flex: 0 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 6px 0;
}
.tutor-chip {
  font-size: var(--fs-xs);
  padding: 4px 12px;
  background: var(--bg-input);
  border: 1px solid var(--br-strong);
  color: var(--tx-2);
  border-radius: 14px;
  cursor: pointer;
  white-space: nowrap;
  transition: all 120ms ease;
  font-family: inherit;
}
.tutor-chip:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
  background: var(--accent-bg);
}
.tutor-chip:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* Empty state */
.tutor-empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 32px 16px;
  color: var(--tx-3);
  gap: 6px;
}
.tutor-empty-icon {
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border: 1px solid var(--br-strong);
  border-radius: 50%;
  font-size: var(--fs-lg);
  color: var(--accent-dim);
  margin-bottom: 8px;
}
.tutor-empty-state p {
  margin: 0;
  font-size: var(--fs-sm);
}
.tutor-empty-state .meta {
  font-size: var(--fs-xs);
}

/* Ref-answer card — sits between thread and composer. */
.tutor-ref-card {
  margin-top: 6px;
  border: 1px solid var(--accent-dim);
  border-radius: var(--r);
  background: var(--bg-input);
  overflow: hidden;
}
.tutor-ref-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 6px 10px;
  background: var(--accent-bg);
  color: var(--accent);
  font-size: var(--fs-xs);
  border-bottom: 1px solid var(--accent-dim);
}
.tutor-ref-card .tutor-refsql {
  margin: 0;
  padding: 10px 12px;
  border: 0;
  border-left: 0;
  background: transparent;
  font-size: var(--fs-sm);
  max-height: 240px;
  overflow: auto;
}
.tutor-ref-card .tutor-refsql code { font: inherit; background: transparent; }

/* Header extra slot — the Tutor panel uses it for the ref-answer button. */
.pf-header-extra {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  flex-shrink: 0;
}
.pf-header-extra .pf-action,
.pf-header-extra .pf-action-ref {
  padding: 4px 14px;
  height: auto;
  min-width: 88px;
  font-size: var(--fs-xs);
  font-family: inherit;
  background: transparent;
  border: 1px solid var(--accent-dim);
  color: var(--accent);
  border-radius: 3px;
  cursor: pointer;
  white-space: nowrap;
  transition: all 120ms ease;
}
.pf-header-extra .pf-action:hover,
.pf-header-extra .pf-action-ref:hover {
  background: var(--accent-bg);
  border-color: var(--accent);
}
.pf-header-extra .pf-action:disabled,
.pf-header-extra .pf-action-ref:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  border-color: var(--br);
  color: var(--tx-3);
}

/* Make sure the panel header lays out title/meta/extra/actions on one row
   with the meta truncating instead of pushing the buttons out. */
.pf-header { flex-wrap: nowrap; }
.pf-meta {
  flex: 1 1 auto;
  min-width: 0;
}


/* Sub-controls in the Setup panel */
.field-row { display: flex; flex-direction: column; gap: 6px; }
.field-label {
  font-size: var(--fs-xs);
  color: var(--tx-3);
  text-transform: lowercase;
  letter-spacing: 0.04em;
  display: flex; align-items: center; gap: 8px;
}
.compact-row { display: flex; flex-wrap: wrap; gap: 6px; }
.theme-option {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px;
  border: 1px solid var(--br);
  border-radius: var(--r);
  cursor: pointer;
  background: var(--bg-input);
  font-size: var(--fs-sm);
  transition: all 120ms ease;
}
.theme-option:hover { border-color: var(--br-strong); }
.theme-option-selected {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
}
.theme-option input { accent-color: var(--accent); margin: 0; }
.theme-custom { display: flex; flex-direction: column; gap: 6px; margin-top: 4px; }
.theme-custom textarea {
  background: var(--bg-input);
  color: var(--tx);
  border: 1px solid var(--br);
  border-radius: var(--r);
  padding: 8px;
  font: inherit;
  resize: vertical;
}
.diff-btn {
  display: flex; flex-direction: column; align-items: flex-start;
  padding: 4px 10px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
  color: var(--tx-2);
  cursor: pointer;
  font-family: inherit;
  transition: all 120ms ease;
}
.diff-btn:hover { border-color: var(--br-strong); color: var(--tx); }
.diff-btn.active {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
}
.diff-level { font-weight: 700; font-size: var(--fs-sm); line-height: 1.2; }
.diff-label { font-size: var(--fs-xxs); color: inherit; opacity: 0.85; line-height: 1.2; }
.diff-hint {
  font-size: var(--fs-xs);
  color: var(--tx-3);
  margin: 0;
}
.topic-chips-list {
  display: flex; flex-wrap: wrap; gap: 3px;
  max-height: 180px;
  overflow-y: auto;
}
/* chip pill — used by topic picker (.topic-chips-list) and any other
   "tag-like" toggle. Single source of truth for the chip aesthetic. */
.chip {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 2px 8px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: 999px;
  font-size: var(--fs-xs);
  cursor: pointer;
  user-select: none;
  transition: all 120ms ease;
  line-height: 1.4;
  color: var(--tx-2);
}
.chip:hover { border-color: var(--br-strong); color: var(--tx); }
.chip-selected {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
}
.chip input { display: none; }
.meta { color: var(--tx-3); font-size: var(--fs-xs); }
.meta-ok { color: var(--accent); }

/* Compact field-row spacing inside the question-gen panel. */
.practice-side .field-row { gap: 4px; }
.practice-side .compact-row { gap: 4px; }

/* Question prompt panel */
.question-meta { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 8px; }
.badge {
  display: inline-block;
  padding: 2px 8px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: 999px;
  font-size: var(--fs-xs);
  color: var(--tx-2);
}
.badge-difficulty {
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 700;
}
.question-prompt {
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-left: 3px solid var(--accent);
  border-radius: var(--r);
  padding: 12px 14px;
  font-size: var(--fs-md);
  line-height: 1.7;
  white-space: pre-wrap;
  color: var(--tx);
}
.question-empty {
  color: var(--tx-3);
  font-style: italic;
  padding: 14px;
  text-align: center;
}

/* Reference answer inside question card */
.question-ref-section {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--br);
}
.question-ref-btn {
  font-size: var(--fs-xs);
  padding: 4px 14px;
  min-width: 88px;
  width: auto;
  text-align: center;
  background: transparent;
  border: 1px solid var(--accent-dim);
  color: var(--accent);
  border-radius: 3px;
  cursor: pointer;
  white-space: nowrap;
  transition: all 120ms ease;
}
.question-ref-btn:hover {
  background: var(--accent-bg);
  border-color: var(--accent);
}
.question-ref-sql {
  margin-top: 8px;
  padding: 10px 12px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono);
  font-size: var(--fs-sm);
  line-height: 1.5;
  white-space: pre-wrap;
  overflow-x: auto;
  color: var(--tx);
}
/* The <code> wrapper inherits the browser default (typically Courier),
   which clashes with the JetBrains Mono used everywhere else. Force it
   to inherit from <pre> so syntax-highlighted spans pick up var(--mono).
   Same trick used by .sql-editor-mirror code and .history-sql code. */
.question-ref-sql code {
  font: inherit;
  background: transparent;
  padding: 0;
  border: 0;
  color: inherit;
}

/* Custom question prompt textarea */
.qgen-body {
  display: flex;
  flex-direction: column;
  height: 100%;
}
.qgen-custom-input {
  width: 100%;
  min-height: 44px;
  max-height: 120px;
  resize: vertical;
  margin-top: 8px;
  padding: 8px 10px;
  background: var(--bg-input);
  border: 1px solid var(--br-strong);
  border-radius: var(--r);
  color: var(--tx);
  font-size: var(--fs-base);
  line-height: 1.5;
}

/* ─── 「出题」 console identity ───
   The panel hosts a one-shot configuration action. (The previous
   accent left-edge stripe was removed at user request — the mono meta
   text in the header is enough to set it apart from the question
   panel above it.) */
.practice-side > [data-panel-role="qgen"] > .pf-header > .pf-meta {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  color: var(--tx-2);
  letter-spacing: 0.02em;
}
.practice-side > [data-panel-role="qgen"].pf-collapsed > .pf-header > .pf-meta {
  color: var(--accent);
}

/* Toolbar buttons inside the qgen panel header (collapsed state).
   We deliberately use smaller padding + neutral colour so they read as
   "controls", not as primary CTAs. */
.qgen-toolbar-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 9px;
  font-size: var(--fs-xs);
  font-family: var(--mono);
  background: transparent;
  border: 1px solid var(--br-strong);
  color: var(--tx-2);
  border-radius: 3px;
  cursor: pointer;
  white-space: nowrap;
  transition: all 120ms ease;
  min-width: 0;        /* override pf-header-extra .pf-action min-width */
}
.qgen-toolbar-btn:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
  background: var(--accent-bg);
}
.qgen-toolbar-btn[data-action="qgen-reroll"] {
  border-color: var(--accent-dim);
  color: var(--accent);
  background: var(--accent-bg);
  font-weight: 600;
}
.qgen-toolbar-btn[data-action="qgen-reroll"]:hover {
  background: var(--accent);
  color: var(--bg);
}
.qgen-toolbar-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  border-color: var(--br);
  color: var(--tx-3);
  background: transparent;
}
/* Toolbar buttons override the generic pf-header-extra .pf-action rule
   so they don't pick up the chunky 88px min-width. */
.pf-header-extra .qgen-toolbar-btn {
  min-width: 0;
  padding: 3px 9px;
  height: auto;
}

/* ──────────────────────────────────────────────────
   Panel component (createPanel)
   ────────────────────────────────────────────────── */
.pf {
  display: flex;
  flex-direction: column;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  overflow: hidden;
  min-height: 0;
}
.pf-header {
  display: flex; align-items: center; gap: 8px;
  padding: 8px 12px;
  background: var(--bg-panel-2);
  border-bottom: 1px solid var(--br);
  user-select: none;
}
.pf-title {
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 0.02em;
}
.pf-meta {
  flex: 1;
  font-size: var(--fs-xs);
  color: var(--tx-3);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.pf-actions { display: flex; gap: 4px; flex-shrink: 0; }
.pf-action {
  width: 24px; height: 22px;
  display: inline-flex; align-items: center; justify-content: center;
  border: 1px solid transparent;
  background: transparent;
  color: var(--tx-2);
  cursor: pointer;
  border-radius: 3px;
  font-family: inherit;
  font-size: var(--fs-sm);
  padding: 0;
  transition: all 120ms ease;
}
.pf-action:hover {
  color: var(--accent);
  background: var(--accent-bg);
  border-color: var(--accent-dim);
}
.pf-body {
  padding: var(--gap-sm);
  /* native vertical resize handle is provided by `resize: vertical` set
     on the host inline; keep min-height generous so the handle is reachable. */
  min-height: 80px;
}
.pf-collapsed > .pf-body { display: none; }
.pf-collapsed > .pf-header { border-bottom: 0; }

/* Hover-popover variant — when collapsed, the header looks like a tab. */
.pf-pophover.pf-collapsed > .pf-header {
  cursor: pointer;
}
.pf-popover {
  background: var(--bg-panel);
  border: 1px solid var(--br-strong);
  border-radius: var(--r);
  box-shadow: 0 12px 40px rgba(0,0,0,0.6);
  padding: var(--gap-sm);
  max-height: 70vh;
  overflow: auto;
  z-index: 1300;
}

/* Fullscreen — pin to viewport, dim everything else. */
.pf-fullscreen {
  position: fixed !important;
  inset: 16px;
  z-index: 1400;
  box-shadow: 0 24px 80px rgba(0,0,0,0.7);
  border: 1px solid var(--accent-dim);
}
.pf-fullscreen > .pf-body {
  /* a fullscreen panel should fill its frame and ignore the original
     resize handle. */
  resize: none !important;
  overflow: auto;
  flex: 1;
  min-height: 0;
}
.pf-fullscreen { display: flex; flex-direction: column; }
body.pf-has-fullscreen::before {
  content: "";
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  z-index: 1399;
}

/* ──────────────────────────────────────────────────
   SQL syntax highlighting
   Used by both the live editor mirror and static <pre>s in tutor / refSql.
   ────────────────────────────────────────────────── */
.sql-kw   { color: var(--magenta); font-weight: 600; }
.sql-str  { color: var(--warn); }
.sql-num  { color: var(--info); }
.sql-com  { color: var(--tx-3); font-style: italic; }
.sql-id   { color: var(--tx); }
.sql-op   { color: var(--accent); }
.sql-punc { color: var(--tx-2); }

/* ──────────────────────────────────────────────────
   Live highlighted SQL editor (gutter + mirror + textarea overlay).
   Layout (left → right):
     [gutter (line numbers)]  [stage: mirror + textarea]
   The stage is a positioning context: mirror absolutely fills it, the
   textarea also fills it with transparent text so the caret sits on
   top of the highlighted mirror.
   ────────────────────────────────────────────────── */
.sql-editor-host { width: 100%; height: 100%; display: flex; }
.sql-editor-wrap {
  position: relative;
  flex: 1;
  display: flex;
  flex-direction: row;
  border: 1px solid var(--br);
  border-radius: var(--r);
  background: var(--bg-input);
  font-family: var(--mono);
  font-size: var(--fs-md);
  line-height: 1.55;
  min-height: 200px;
  overflow: hidden;
}
.sql-editor-wrap:focus-within { border-color: var(--accent); }

/* CodeMirror 6 host — the `.cm-editor` is created inside `.sql-editor-wrap`
   by createHighlightedEditor. Stretch it to fill so the editor scales
   with whatever container the practice / dual / settings view drops it
   into. Most colour decisions live inline via EditorView.theme() so we
   only handle layout + a few stubbornly-internal CodeMirror styles
   (focus outline, panels) here. */
.sql-editor-wrap > .cm-editor {
  width: 100%;
  height: 100%;
  flex: 1;
  min-height: 0;
}
.sql-editor-wrap > .cm-editor.cm-focused {
  outline: none;
}
.sql-editor-wrap .cm-panels {
  background: var(--bg-panel-2);
  color: var(--tx);
  border-color: var(--br);
}
.sql-editor-wrap .cm-panel input {
  background: var(--bg-input);
  color: var(--tx);
  border: 1px solid var(--br-strong);
  border-radius: var(--r);
  padding: 4px 8px;
}

/* Gutter — line numbers, monospace, right-aligned. */
.sql-editor-gutter {
  flex: 0 0 auto;
  width: 44px;
  padding: 12px 8px 12px 0;
  margin: 0;
  background: var(--bg);
  border-right: 1px solid var(--br);
  color: var(--tx-3);
  font: inherit;
  line-height: inherit;
  text-align: right;
  user-select: none;
  pointer-events: none;
  overflow: hidden;
  white-space: nowrap;
  position: relative;
}
.sql-editor-gutter-inner {
  /* Slid up/down via transform when the user scrolls the textarea so
     line numbers always line up with the corresponding source lines. */
  position: absolute;
  top: 12px;
  right: 8px;
  left: 0;
  will-change: transform;
}
.sql-editor-gutter .sql-editor-ln {
  display: block;
  font-variant-numeric: tabular-nums;
  text-align: right;
  padding-right: 0;
}

.sql-editor-stage {
  position: relative;
  flex: 1;
  min-width: 0;
  overflow: hidden;
}
.sql-editor-mirror {
  position: absolute;
  inset: 0;
  margin: 0;
  padding: 12px 14px;
  border: 0;
  font: inherit;
  letter-spacing: 0;
  white-space: pre-wrap;
  word-break: break-word;
  overflow-wrap: anywhere;
  tab-size: 2;
  pointer-events: none;
  color: var(--tx);
  background: transparent;
  overflow: auto;
}
.sql-editor-mirror code {
  display: block;
  font: inherit;
  background: transparent;
  border: 0;
  padding: 0;
  color: inherit;
}
/* Textarea sits on top of the mirror inside the stage. */
.sql-editor-stage > .sql-editor-textarea {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 12px 14px;
  border: 0;
  font: inherit;
  letter-spacing: 0;
  white-space: pre-wrap;
  word-break: break-word;
  overflow-wrap: anywhere;
  tab-size: 2;
  background: transparent !important;
  color: transparent !important;
  caret-color: var(--accent) !important;
  resize: none !important;
  outline: none;
  overflow: auto;
}
.sql-editor-stage > .sql-editor-textarea::placeholder {
  color: var(--tx-3) !important;
}
.sql-editor-stage > .sql-editor-textarea::selection {
  background: rgba(166, 227, 161, 0.25);
  color: transparent !important;
}

.editor-actions {
  display: flex; gap: 10px; padding: 10px 0 0;
  flex-wrap: wrap;
}

.dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap-sm);
}
@media (max-width: 800px) { .dual-grid { grid-template-columns: 1fr; } }
.practice-main [data-editor-mount] > .dual-editor-view {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}
.practice-main .dual-editor-view > .dual-grid {
  flex: 1;
  min-height: 0;
}
.practice-main .dual-pane {
  display: flex;
  flex-direction: column;
  min-height: 0;
  min-width: 0;
}
.practice-main .dual-pane > .sql-editor-host {
  flex: 1;
  min-height: 0;
}
.practice-main .dual-pane > .sql-editor-host > .sql-editor-wrap {
  flex: 1;
  min-height: 0;
}
.dual-pane h4 {
  margin: 0 0 6px;
  color: var(--tx-2);
  font-size: var(--fs-sm);
  flex: 0 0 auto;
}

/* ──────────────────────────────────────────────────
   Markdown rendering inside Tutor messages
   ────────────────────────────────────────────────── */
.markdown { color: var(--tx); }
.markdown > *:first-child { margin-top: 0; }
.markdown > *:last-child  { margin-bottom: 0; }
.markdown .md-heading {
  margin: 14px 0 6px;
  color: var(--accent);
  font-weight: 600;
  font-size: var(--fs-md);
  line-height: 1.4;
}
.markdown h1.md-heading { font-size: var(--fs-lg); }
.markdown h2.md-heading { font-size: var(--fs-md); }
.markdown h3.md-heading,
.markdown h4.md-heading,
.markdown h5.md-heading,
.markdown h6.md-heading { font-size: var(--fs-base); }
.markdown .md-p   { margin: 6px 0; line-height: 1.7; }
.markdown .md-list {
  margin: 6px 0;
  padding-left: 1.4em;
  display: flex; flex-direction: column; gap: 2px;
}
.markdown .md-list li::marker { color: var(--accent); }
.markdown .md-quote {
  margin: 8px 0;
  padding: 6px 12px;
  border-left: 3px solid var(--accent-dim);
  color: var(--tx-2);
  background: var(--accent-bg);
}
.markdown .md-inline-code {
  background: var(--bg-input);
  border: 1px solid var(--br);
  padding: 1px 5px;
  border-radius: 3px;
  font-size: var(--fs-xs);
  color: var(--warn);
}
.markdown .md-code {
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
  padding: 10px 12px;
  margin: 8px 0;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: var(--fs-sm);
  line-height: 1.5;
}
.markdown .md-code code {
  background: transparent;
  border: 0;
  padding: 0;
  color: var(--tx);
  font: inherit;
}
.markdown a {
  color: var(--info);
  text-decoration: underline;
  text-underline-offset: 2px;
}
.markdown a:hover { color: var(--accent); }

/* ──────────────────────────────────────────────────
   Tutor view tweaks for Markdown + reference SQL
   ────────────────────────────────────────────────── */
.tutor-content { width: 100%; min-width: 0; }
.tutor-content-user { white-space: pre-wrap; word-break: break-word; }
.tutor-msg { list-style: none; }
.tutor-refsql {
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-left: 3px solid var(--accent);
  border-radius: var(--r);
  padding: 10px 12px;
  margin: 8px 0;
  font-family: var(--mono);
  font-size: var(--fs-sm);
  white-space: pre-wrap;
  overflow-x: auto;
}
.tutor-refsql code { font: inherit; background: transparent; }

/* ──────────────────────────────────────────────────
   Database manager (替换原"主题"面板)
   ────────────────────────────────────────────────── */
.db-saved-list {
  display: flex; flex-direction: column; gap: 4px;
  margin: 0; padding: 0; list-style: none;
}
.db-saved-item {
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: 6px;
  align-items: center;
  padding: 6px 10px;
  border: 1px solid var(--br);
  border-radius: var(--r);
  background: var(--bg-input);
  font-size: var(--fs-xs);
  color: var(--tx);
  cursor: pointer;
  transition: all 120ms ease;
}
.db-saved-item:hover { border-color: var(--br-strong); }
.db-saved-item.db-saved-active {
  border-color: var(--accent);
  background: var(--accent-bg);
  color: var(--accent);
}
.db-saved-meta {
  font-size: var(--fs-xxs);
  color: var(--tx-3);
  white-space: nowrap;
}
.db-saved-actions { display: flex; gap: 4px; }
.db-icon-btn {
  width: 22px; height: 20px;
  border: 1px solid var(--br);
  background: transparent;
  color: var(--tx-2);
  cursor: pointer;
  border-radius: 3px;
  font-size: var(--fs-xs);
  display: inline-flex; align-items: center; justify-content: center;
  transition: all 120ms ease;
}
.db-icon-btn:hover { color: var(--accent); border-color: var(--accent); }
.db-icon-btn.danger:hover { color: var(--fail); border-color: var(--fail); }
.db-section-divider {
  border: 0;
  border-top: 1px dashed var(--br);
  margin: 12px 0 8px;
}
.db-section-title {
  font-size: var(--fs-xs);
  color: var(--tx-3);
  text-transform: lowercase;
  letter-spacing: 0.04em;
  margin: 0 0 6px;
}
.db-import-row {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  margin-top: 4px;
}
.db-import-row input[type="file"] {
  font-size: var(--fs-xs);
  color: var(--tx-2);
  flex: 1;
  min-width: 0;
}
.db-info-popover {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: var(--fs-xs);
  color: var(--tx-2);
}
.db-info-popover h5 {
  margin: 0;
  color: var(--accent);
  font-size: var(--fs-sm);
}
.db-info-tables {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 4px 12px;
}
.db-info-tables span:nth-child(odd) { color: var(--tx); }
.db-info-tables span:nth-child(even) { color: var(--tx-3); text-align: right; }

/* Practice panel bodies must pass the column height down to nested editor /
   result / tutor views. Column splitters handle resizing in this layout. */
.practice-side .pf-body,
.practice-main .pf-body,
.practice-tutor .pf-body {
  resize: none;
  overflow: auto;
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  max-height: none;
}

/* ──────────────────────────────────────────────────
   Database tab — full-page two-column layout
   ────────────────────────────────────────────────── */
.db-route {
  display: grid;
  grid-template-columns: minmax(280px, 360px) minmax(0, 1fr);
  gap: var(--gap-md);
  padding: var(--gap-md);
  align-items: start;
  min-height: calc(100vh - 60px);
}
@media (max-width: 800px) {
  .db-route { grid-template-columns: 1fr; }
}
.db-route-side {
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  padding: var(--gap-md);
  display: flex;
  flex-direction: column;
  gap: 8px;
  position: sticky;
  top: 64px;
  max-height: calc(100vh - 80px);
  overflow: auto;
}
.db-route-section-title {
  margin: 0 0 4px;
  font-size: var(--fs-xs);
  text-transform: lowercase;
  letter-spacing: 0.04em;
  color: var(--tx-3);
  font-weight: 500;
}
.db-saved-list { gap: 4px; }
.db-saved-item.db-saved-focus {
  outline: 1px solid var(--accent-dim);
}
.db-saved-name {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.db-route-main {
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-radius: var(--r);
  padding: var(--gap-md);
  min-height: 280px;
  min-width: 0;
}
.db-route-empty {
  text-align: center;
  padding: var(--gap-lg);
  color: var(--tx-2);
}
.db-route-empty p { margin: 6px 0; }
.db-route-detail-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--gap-md);
  border-bottom: 1px solid var(--br);
  padding-bottom: var(--gap-sm);
  margin-bottom: var(--gap-md);
}
.db-route-name {
  margin: 0;
  font-size: var(--fs-lg);
  color: var(--accent);
  font-weight: 600;
}
.db-route-active-badge {
  display: inline-block;
  margin-left: 8px;
  padding: 1px 8px;
  background: var(--accent-bg);
  border: 1px solid var(--accent);
  border-radius: 999px;
  font-size: var(--fs-xxs);
  color: var(--accent);
}
.db-route-detail-actions {
  display: flex; gap: 8px;
}
.db-route-tables {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(320px, 100%), 1fr));
  gap: var(--gap-md);
  margin-bottom: var(--gap-md);
}
.db-route-table {
  border: 1px solid var(--br);
  border-radius: var(--r);
  background: var(--bg-input);
  padding: 12px;
  min-width: 0;
  overflow: auto;
}
.db-route-table-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 8px;
}
.db-route-table-head h4 {
  margin: 0;
  color: var(--tx);
  font-size: var(--fs-md);
  font-weight: 600;
}
.db-route-ddl {
  border: 1px solid var(--br);
  border-radius: var(--r);
  background: var(--bg-input);
  margin-top: var(--gap-sm);
}
.db-route-ddl > summary {
  cursor: pointer;
  padding: 8px 12px;
  color: var(--tx-2);
  font-size: var(--fs-sm);
  user-select: none;
}
.db-route-ddl > summary:hover { color: var(--accent); }
.db-route-ddl > pre {
  margin: 0;
  padding: 12px;
  border-top: 1px solid var(--br);
  border-radius: 0 0 var(--r) var(--r);
  border-left: 0;
  overflow-x: auto;
  overflow-wrap: anywhere;
}

/* Database page packs a lot of identifiers into narrow card grid cells.
   Scope a one-step-down typography pass so long table/column names fit
   without truncation while keeping the sidebar/heading hierarchy. */
.db-route-name { font-size: var(--fs-md); }
.db-route-table-head h4,
.db-route-main .schema-table h4 { font-size: var(--fs-sm); }
.db-route-main .schema-cols { font-size: var(--fs-xxs); }
.db-route-main .schema-cols th,
.db-route-main .schema-cols td { padding-left: 8px; padding-right: 8px; }
.db-route-main .schema-pk,
.db-route-main .schema-fk { font-size: var(--fs-xxs); }
.db-route-main .db-route-ddl > summary { font-size: var(--fs-xs); }
.db-route-main .db-route-ddl > pre { font-size: var(--fs-xs); }

/* ──────────────────────────────────────────────────
   History view (May 2026 v2)
   ────────────────────────────────────────────────── */
.history-stats { flex: 1; }
.history-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-bottom: var(--gap-md);
  padding: 10px 12px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
}
.history-select {
  padding: 4px 8px;
  background: var(--bg-panel);
  border: 1px solid var(--br-strong);
  color: var(--tx);
  border-radius: var(--r);
  font: inherit;
  font-size: var(--fs-xs);
}
.history-search {
  flex: 1;
  min-width: 200px;
  padding: 4px 10px;
  background: var(--bg-panel);
  border: 1px solid var(--br-strong);
  color: var(--tx);
  border-radius: var(--r);
  font: inherit;
  font-size: var(--fs-xs);
}
.history-search:focus { outline: none; border-color: var(--accent); }

.history-item {
  display: flex; flex-direction: column;
  gap: 8px;
  padding: 12px 14px;
  background: var(--bg-panel);
  border: 1px solid var(--br);
  border-left: 3px solid var(--tx-mute);
  border-radius: var(--r);
  margin-bottom: 8px;
  position: static;
  transition: border-left-color 120ms ease;
}
.history-item::before { content: none; }
/* Tri-state question status — drives the left-edge stripe colour and
   the verdict pill. `data-question-status` is the new authoritative
   attribute (correct/recovered/wrong/pending). The old
   `data-history-correct` attribute is kept in the DOM for backward
   compat but no longer drives styling. */
.history-item[data-question-status="correct"]   { border-left-color: var(--pass); }
.history-item[data-question-status="recovered"] { border-left-color: var(--warn); }
.history-item[data-question-status="wrong"]     { border-left-color: var(--fail); }
.history-item[data-question-status="pending"]   { border-left-color: var(--tx-mute); }
.history-item-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 10px;
  flex-wrap: wrap;
}
.history-item-meta {
  display: flex; flex-wrap: wrap; gap: 4px;
  align-items: center;
}
.history-item-right {
  display: flex; gap: 10px; align-items: center;
  font-size: var(--fs-xs);
  flex-shrink: 0;
}
.history-item-db { color: var(--tx-3); }
.history-verdict {
  font-weight: 600;
  font-size: var(--fs-xs);
  padding: 2px 8px;
  border-radius: 3px;
}
.history-verdict-ok        { background: var(--pass-bg); color: var(--pass); }
.history-verdict-fail      { background: var(--fail-bg); color: var(--fail); }
/* New tri-state pills (correspond to data-question-status). */
.history-verdict-correct   { background: var(--pass-bg); color: var(--pass); border: 1px solid var(--pass); }
.history-verdict-recovered { background: var(--warn-bg); color: var(--warn); border: 1px solid var(--warn-dim); }
.history-verdict-wrong     { background: var(--fail-bg); color: var(--fail); border: 1px solid var(--fail); }
.history-verdict-pending   { background: transparent;    color: var(--tx-3); border: 1px solid var(--br-strong); }
/* Per-question summary line (e.g. "共 3 次提交，错 2 次，对 1 次") */
.history-item-attempts {
  margin: 4px 0 0;
  font-size: var(--fs-xs);
  color: var(--tx-3);
}
/* Per-attempt section inside the <details> pane — each one is bordered
   green/red so the user can see which submission was right vs wrong. */
.history-attempt {
  margin-top: 10px;
  padding: 8px 10px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-left: 3px solid var(--tx-mute);
  border-radius: var(--r);
}
.history-attempt-ok   { border-left-color: var(--pass); }
.history-attempt-fail { border-left-color: var(--fail); }
.history-attempt-ref  { border-left-color: var(--accent); }
.history-attempt-head {
  display: flex; gap: 8px; align-items: baseline; flex-wrap: wrap;
  margin-bottom: 6px;
}
.history-attempt-idx {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  color: var(--tx-2);
  font-weight: 600;
}
.history-attempt-verdict {
  font-size: var(--fs-xxs);
  font-weight: 600;
  margin-left: auto;
  letter-spacing: 0.04em;
}
.history-attempt-ok   .history-attempt-verdict { color: var(--pass); }
.history-attempt-fail .history-attempt-verdict { color: var(--fail); }
.history-item-prompt {
  margin: 0;
  padding: 8px 10px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
  font-size: var(--fs-sm);
  color: var(--tx);
  white-space: pre-wrap;
  line-height: 1.55;
}
.history-item-details {
  border-top: 1px dashed var(--br);
  padding-top: 8px;
}
.history-item-details > summary {
  cursor: pointer;
  color: var(--tx-3);
  font-size: var(--fs-xs);
  user-select: none;
}
.history-item-details > summary:hover { color: var(--accent); }
.history-item-sqls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 8px;
}
@media (max-width: 800px) {
  .history-item-sqls { grid-template-columns: 1fr; }
}
.history-sql-block h5 {
  margin: 0 0 4px;
  font-size: var(--fs-xs);
  color: var(--tx-3);
  font-weight: 500;
  text-transform: lowercase;
  letter-spacing: 0.04em;
}
.history-item-sqls .history-sql {
  margin: 0;
  padding: 8px 10px;
  background: var(--bg-input);
  border: 1px solid var(--br);
  border-radius: var(--r);
  font-family: var(--mono);
  font-size: var(--fs-xs);
  white-space: pre-wrap;
  word-break: break-word;
  max-height: 260px;
  overflow: auto;
}
.history-item-sqls .history-sql code { font: inherit; background: transparent; }
.history-diff,
.history-sandbox-error { margin-top: 6px; }
.history-sandbox-error { color: var(--fail); }
.history-item-actions { display: flex; justify-content: flex-end; }

/* ──────────────────────────────────────────────────
   History-questions modal (practice → 题目 panel header)
   ────────────────────────────────────────────────── */
.hq-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1200;
  /* See note on .result-modal-backdrop — the dialog host has
     pointer-events:none so each modal must re-enable on its backdrop,
     otherwise the close button and item clicks die silently. */
  pointer-events: auto;
}
.hq-modal-card {
  background: var(--bg-panel);
  border: 1px solid var(--accent-dim);
  border-radius: var(--r);
  width: 640px;
  max-width: 92vw;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 16px 48px rgba(0,0,0,0.6);
}
.hq-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--br);
}
.hq-modal-header h3 {
  margin: 0;
  font-size: var(--fs-lg);
  color: var(--accent);
}
.hq-modal-list {
  list-style: none;
  margin: 0;
  padding: 8px;
  overflow-y: auto;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.hq-modal-item {
  padding: 10px 12px;
  border: 1px solid var(--br);
  border-radius: var(--r);
  background: var(--bg-input);
  cursor: pointer;
  transition: all 120ms ease;
}
.hq-modal-item:hover {
  border-color: var(--accent);
  background: var(--accent-bg);
}
/* Tri-state left bar — visible at a glance which questions still need
   work without having to scroll into the row. Mirrors the history-view
   tri-state palette so the two surfaces feel consistent. */
.hq-modal-item[data-question-status="correct"]   { border-left: 3px solid var(--pass); }
.hq-modal-item[data-question-status="recovered"] { border-left: 3px solid var(--warn); }
.hq-modal-item[data-question-status="wrong"]     { border-left: 3px solid var(--fail); }
.hq-modal-item[data-question-status="pending"]   { border-left: 3px solid var(--tx-mute); }
.hq-modal-status {
  font-size: var(--fs-xxs);
  font-weight: 600;
  padding: 1px 7px;
  border-radius: 999px;
  letter-spacing: 0.04em;
}
.hq-modal-status-correct   { color: var(--pass); border: 1px solid var(--pass);     background: var(--pass-bg); }
.hq-modal-status-recovered { color: var(--warn); border: 1px solid var(--warn-dim); background: var(--warn-bg); }
.hq-modal-status-wrong     { color: var(--fail); border: 1px solid var(--fail);     background: var(--fail-bg); }
.hq-modal-status-pending   { color: var(--tx-3); border: 1px solid var(--br-strong); }
.hq-modal-attempts { color: var(--tx-3); }
.hq-modal-item-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
  margin-bottom: 6px;
}
.hq-modal-item-prompt {
  margin: 0;
  font-size: var(--fs-sm);
  color: var(--tx);
  white-space: pre-wrap;
  line-height: 1.5;
  max-height: 60px;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ──────────────────────────────────────────────────
   Editor + Tutor flex chain — make sure every wrapper passes height
   down so the editor textarea and the tutor thread fill their panels.
   ────────────────────────────────────────────────── */
.practice-main .pf-body > [data-editor-mount],
.practice-main [data-editor-mount] {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  height: 100%;
}
.practice-main [data-editor-mount] > .editor-view {
  flex: 1;
  min-height: 0;
  display: flex;
  flex-direction: column;
}
.practice-main .editor-view > .sql-editor-host {
  flex: 1;
  min-height: 0;
  display: flex;
}
.practice-main .editor-view > .sql-editor-host > .sql-editor-wrap {
  flex: 1;
  min-height: 0;
}

.practice-tutor .pf-body > [data-tutor-mount],
.practice-tutor [data-tutor-mount] {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  height: 100%;
}
.practice-tutor [data-tutor-mount] > .tutor-view {
  flex: 1;
  min-height: 0;
}