/* =========================================================================
   multipage · Material Design 3 baseline (pure CSS, no build)
   Shared by every page. Tokens + chrome + one block per page layout.
   ========================================================================= */

/* ---- MD3 tokens : LIGHT ---- */
:root,
[data-theme="light"] {
  --primary:#6750A4; --on-primary:#FFFFFF; --primary-container:#EADDFF; --on-primary-container:#21005D;
  --secondary:#625B71; --secondary-container:#E8DEF8; --on-secondary-container:#1D192B;
  --tertiary:#7D5260; --tertiary-container:#FFD8E4;
  --background:#FEF7FF; --on-background:#1D1B20; --surface:#FEF7FF;
  --surface-container:#F3EDF7; --surface-container-high:#ECE6F0; --surface-variant:#E7E0EC;
  --on-surface:#1D1B20; --on-surface-variant:#49454F;
  --outline:#79747E; --outline-variant:#CAC4D0; --error:#B3261E; --success:#2E7D32;
  --elev-1:0 1px 2px rgba(0,0,0,.10),0 1px 3px 1px rgba(0,0,0,.06);
  --elev-2:0 2px 6px 2px rgba(0,0,0,.10),0 1px 2px rgba(0,0,0,.12);
  --elev-3:0 4px 8px 3px rgba(0,0,0,.12),0 1px 3px rgba(0,0,0,.14);
  --radius-sm:8px; --radius:16px; --radius-lg:28px;
  --font-body:"Roboto Flex","Roboto","Noto Sans TC",system-ui,sans-serif;
}
/* ---- MD3 tokens : DARK ---- */
[data-theme="dark"] {
  --primary:#D0BCFF; --on-primary:#381E72; --primary-container:#4F378B; --on-primary-container:#EADDFF;
  --secondary:#CCC2DC; --secondary-container:#4A4458; --on-secondary-container:#E8DEF8;
  --tertiary:#EFB8C8; --tertiary-container:#633B48;
  --background:#141218; --on-background:#E6E0E9; --surface:#141218;
  --surface-container:#211F26; --surface-container-high:#2B2930; --surface-variant:#49454F;
  --on-surface:#E6E0E9; --on-surface-variant:#CAC4D0;
  --outline:#938F99; --outline-variant:#49454F; --error:#F2B8B5; --success:#A5D6A7;
}

/* ---- Reset / base ---- */
* { box-sizing:border-box; }
html { scroll-behavior:smooth; }
body {
  margin:0; font-family:var(--font-body); background:var(--background); color:var(--on-background);
  -webkit-font-smoothing:antialiased; transition:background .2s,color .2s; overflow-x:hidden;
}
a { color:inherit; text-decoration:none; }
.material-symbols-rounded { font-variation-settings:"FILL" 0,"wght" 400,"GRAD" 0,"opsz" 24; line-height:1; user-select:none; }
.skip-link {
  position:absolute; left:-999px; top:8px; z-index:60; background:var(--primary); color:var(--on-primary);
  padding:8px 14px; border-radius:var(--radius-lg);
}
.skip-link:focus { left:12px; }

/* ---- App bar ---- */
.appbar { position:sticky; top:0; z-index:30; background:var(--surface-container); box-shadow:var(--elev-1); }
.appbar__inner { max-width:1100px; margin:0 auto; padding:10px 16px; display:flex; align-items:center; gap:12px; }
.brand { display:flex; align-items:center; gap:8px; font-weight:700; font-size:1.1rem; color:var(--on-surface); min-width:0; overflow:hidden; }
.brand__logo { color:var(--primary); flex:0 0 auto; }
.brand__name { overflow:hidden; text-overflow:ellipsis; white-space:nowrap; }
.appbar__actions { margin-left:auto; display:flex; align-items:center; gap:8px; flex:0 0 auto; }
.icon-btn { display:inline-flex; align-items:center; gap:4px; border:none; background:transparent; color:var(--on-surface-variant);
  border-radius:var(--radius-lg); padding:8px 10px; cursor:pointer; font:inherit; transition:background .15s; }
.icon-btn:hover { background:var(--surface-container-high); }
.icon-btn__txt { font-size:.85rem; font-weight:500; }

/* ---- Cross-page nav ---- */
.pagenav {
  position:sticky; top:56px; z-index:25; border-bottom:1px solid var(--outline-variant);
  background:color-mix(in srgb,var(--background) 88%,transparent); backdrop-filter:saturate(180%) blur(8px);
}
.pagenav__inner { max-width:1100px; margin:0 auto; padding:8px 12px; display:flex; gap:8px; overflow-x:auto; scrollbar-width:none; }
.pagenav__inner::-webkit-scrollbar { display:none; }
.navpill {
  display:inline-flex; align-items:center; gap:6px; flex:0 0 auto; padding:7px 14px; border-radius:var(--radius-lg);
  font-size:.85rem; font-weight:500; color:var(--on-surface-variant); border:1px solid var(--outline-variant);
  background:transparent; white-space:nowrap; cursor:pointer; transition:background .15s,color .15s,border-color .15s;
}
.navpill .material-symbols-rounded { font-size:18px; }
.navpill:hover { background:var(--surface-container-high); }
.navpill--active { background:var(--secondary-container); color:var(--on-secondary-container); border-color:transparent; }

/* ---- Page scaffold ---- */
.page { max-width:1100px; margin:0 auto; padding:32px 16px 16px; }
.page-head { margin-bottom:22px; }
.page-head h1 { margin:0 0 6px; font-size:clamp(1.6rem,4vw,2.2rem); font-weight:700; letter-spacing:-.01em; color:var(--on-surface); }
.page-head__sub { margin:0; max-width:62ch; font-size:1rem; line-height:1.5; color:var(--on-surface-variant); }
.empty { color:var(--on-surface-variant); }

/* ---- Hero stats (hub) ---- */
.hero__stats { display:grid; grid-template-columns:repeat(auto-fit,minmax(140px,1fr)); gap:14px; margin:0 0 26px; }
.hero__stat { background:var(--surface-container); border-radius:var(--radius); padding:20px 18px; display:flex; flex-direction:column; gap:4px; border:1px solid var(--outline-variant); }
.hero__stat-value { font-size:2rem; font-weight:700; color:var(--primary); font-variant-numeric:tabular-nums; line-height:1.1; }
.hero__stat-label { font-size:.85rem; color:var(--on-surface-variant); }

/* ---- Cards grid ---- */
.grid { display:grid; grid-template-columns:repeat(auto-fill,minmax(260px,1fr)); gap:16px; }
.card { background:var(--surface-container); border-radius:var(--radius); padding:20px; cursor:pointer;
  border:1px solid transparent; transition:box-shadow .18s,transform .18s,border-color .18s; display:flex; flex-direction:column; gap:10px; }
.card:hover,.card:focus-visible { box-shadow:var(--elev-2); transform:translateY(-2px); border-color:var(--outline-variant); outline:none; }
.card--nav .card__icon { font-size:28px; color:var(--primary); }
.card__title { margin:0; font-size:1.05rem; font-weight:600; color:var(--on-surface); }
.card__summary { margin:0; font-size:.9rem; line-height:1.5; color:var(--on-surface-variant); }
.card__tags { margin-top:auto; display:flex; flex-wrap:wrap; gap:6px; }
.tag { font-size:.72rem; color:var(--on-surface-variant); background:var(--surface-variant); padding:2px 8px; border-radius:var(--radius-sm); }

/* ---- Toolbar / search / chips ---- */
.toolbar { display:flex; flex-wrap:wrap; gap:12px; align-items:center; margin-bottom:14px; }
.search { flex:1 1 220px; min-width:160px; padding:10px 14px; border-radius:var(--radius-lg); border:1px solid var(--outline-variant);
  background:var(--surface-container); color:var(--on-surface); font:inherit; }
.search:focus { outline:2px solid var(--primary); outline-offset:1px; }
.chips { display:flex; flex-wrap:wrap; gap:8px; }
.chip { padding:7px 14px; border-radius:var(--radius-lg); font-size:.85rem; font-weight:500; color:var(--on-surface-variant);
  border:1px solid var(--outline-variant); background:transparent; cursor:pointer; transition:background .15s,color .15s; }
.chip:hover { background:var(--surface-container-high); }
.chip--active { background:var(--secondary-container); color:var(--on-secondary-container); border-color:transparent; }
.result-count { margin:0 0 14px; font-size:.85rem; color:var(--on-surface-variant); }

/* ---- Article ---- */
.reading-progress { position:fixed; top:0; left:0; height:3px; width:0; background:var(--primary); z-index:40; transition:width .1s linear; }
.article-layout { display:grid; grid-template-columns:200px 1fr; gap:32px; align-items:start; }
.toc { position:sticky; top:108px; }
.toc__inner { display:flex; flex-direction:column; gap:4px; border-left:2px solid var(--outline-variant); }
.toc-link { padding:6px 14px; font-size:.9rem; color:var(--on-surface-variant); border-left:2px solid transparent; margin-left:-2px; }
.toc-link:hover { color:var(--on-surface); }
.toc-link--active { color:var(--primary); border-left-color:var(--primary); font-weight:600; }
.prose { max-width:70ch; color:var(--on-surface-variant); }
.prose h2 { color:var(--on-surface); font-size:1.4rem; margin:0 0 12px; scroll-margin-top:120px; }
.prose h3 { color:var(--on-surface); font-size:1.12rem; margin:22px 0 8px; }
.prose p { line-height:1.75; margin:0 0 14px; }
.prose ul { margin:0 0 14px; padding-left:22px; line-height:1.75; }
.prose blockquote { margin:0 0 16px; padding:8px 18px; border-left:4px solid var(--primary); color:var(--on-surface); font-style:italic; }
.prose pre { background:var(--surface-container); padding:14px 16px; border-radius:var(--radius); overflow:auto; border:1px solid var(--outline-variant); }
.prose code { font-family:"Roboto Mono",ui-monospace,monospace; font-size:.85rem; }
.article-section { margin-bottom:28px; }

/* ---- Dashboard ---- */
.stat-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(160px,1fr)); gap:16px; margin-bottom:20px; }
.stat-card { background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:18px; display:flex; flex-direction:column; gap:6px; }
.stat-label { font-size:.82rem; color:var(--on-surface-variant); }
.stat-value { font-size:1.6rem; font-weight:700; color:var(--on-surface); font-variant-numeric:tabular-nums; }
.stat-unit { font-size:.85rem; font-weight:500; color:var(--on-surface-variant); }
.stat-delta { font-size:.8rem; font-weight:600; }
.stat-delta--up { color:var(--success); }
.stat-delta--down { color:var(--error); }
.panel-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(280px,1fr)); gap:16px; margin-bottom:20px; }
.panel { margin:0; background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:18px; }
.panel figcaption { font-weight:600; color:var(--on-surface); margin-bottom:10px; }
.panel--wide { grid-column:1/-1; }
.chart-wrap { width:100%; }
.chart-wrap svg { width:100%; height:auto; display:block; }
.bar-rect { fill:var(--primary); transition:fill .15s; }
.bar-rect:hover { fill:var(--tertiary); }
.bar-value { fill:var(--on-surface); font-size:13px; font-weight:600; font-family:var(--font-body); }
.bar-label { fill:var(--on-surface-variant); font-size:12px; font-family:var(--font-body); }
.axis-line { stroke:var(--outline-variant); stroke-width:1.5; }
.line-path { stroke:var(--primary); stroke-width:2.5; }
.line-area { fill:var(--primary); opacity:.12; }
.line-dot { fill:var(--primary); }

/* ---- Data table ---- */
.table-wrap { overflow-x:auto; border-radius:var(--radius); border:1px solid var(--outline-variant); }
.data-table,.cmp-table { width:100%; border-collapse:collapse; background:var(--surface-container); font-size:.9rem; }
.data-table th,.data-table td { padding:11px 14px; text-align:left; border-bottom:1px solid var(--outline-variant); color:var(--on-surface); white-space:nowrap; }
.data-table thead th { background:var(--surface-container-high); font-weight:600; color:var(--on-surface-variant); position:sticky; top:0; }
.th-sort { cursor:pointer; user-select:none; }
.th-sort:hover { color:var(--primary); }
.data-table tbody tr:hover { background:var(--surface-container-high); }
.row-link { color:var(--primary); }

/* ---- Timeline ---- */
.timeline { list-style:none; margin:0; padding:0; position:relative; }
.timeline::before { content:""; position:absolute; left:7px; top:6px; bottom:6px; width:2px; background:var(--outline-variant); }
.tl-item { position:relative; padding:0 0 18px 36px; }
.tl-item:last-child { padding-bottom:0; }
.tl-dot { position:absolute; left:0; top:6px; width:16px; height:16px; border-radius:50%; background:var(--primary); border:3px solid var(--background); box-shadow:0 0 0 2px var(--primary); }
.tl-card { background:var(--surface-container); border-radius:var(--radius); padding:14px 18px; border:1px solid var(--outline-variant); }
.tl-date { font-size:.78rem; font-weight:600; letter-spacing:.04em; color:var(--primary); }
.tl-title { margin:4px 0 6px; font-size:1.05rem; color:var(--on-surface); }
.tl-body { margin:0; font-size:.9rem; line-height:1.5; color:var(--on-surface-variant); }

/* ---- Bento ---- */
.bento { display:grid; grid-template-columns:repeat(4,1fr); grid-auto-rows:120px; gap:14px; }
.tile { background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:18px; display:flex; flex-direction:column; gap:6px; overflow:hidden; }
.tile--accent { background:linear-gradient(135deg,var(--primary-container),var(--secondary-container)); border-color:transparent; }
.tile--lg { grid-column:span 2; grid-row:span 2; }
.tile--tall { grid-row:span 2; }
.tile--wide { grid-column:span 2; }
.tile--md { grid-column:span 2; }
.tile__icon { font-size:26px; color:var(--primary); }
.tile__value { font-size:1.7rem; font-weight:700; color:var(--on-surface); }
.tile__title { margin:0; font-size:1rem; color:var(--on-surface); }
.tile__body { margin:0; font-size:.85rem; line-height:1.45; color:var(--on-surface-variant); }

/* ---- Kanban ---- */
.kanban { display:grid; grid-auto-flow:column; grid-auto-columns:minmax(240px,1fr); gap:14px; overflow-x:auto; padding-bottom:8px; }
.kb-col { background:var(--surface-container-high); border-radius:var(--radius); padding:12px; }
.kb-col__head { display:flex; align-items:center; gap:8px; font-weight:600; color:var(--on-surface); margin-bottom:10px; padding:0 4px; }
.kb-col__count { font-size:.75rem; background:var(--secondary-container); color:var(--on-secondary-container); border-radius:var(--radius-lg); padding:1px 8px; }
.kb-col__body { display:flex; flex-direction:column; gap:10px; }
.kb-card { background:var(--surface); border:1px solid var(--outline-variant); border-radius:var(--radius-sm); padding:12px 14px; display:flex; flex-direction:column; gap:8px; }
.kb-card__title { margin:0; font-size:.95rem; color:var(--on-surface); }
.kb-card__body { margin:0; font-size:.82rem; line-height:1.45; color:var(--on-surface-variant); }

/* ---- Accordion (faq) ---- */
.accordion { display:flex; flex-direction:column; gap:10px; }
.acc-item { background:var(--surface-container); border-radius:var(--radius); border:1px solid var(--outline-variant); overflow:hidden; }
.acc-q { display:flex; align-items:center; justify-content:space-between; gap:12px; padding:16px 18px; cursor:pointer; font-weight:600; color:var(--on-surface); list-style:none; }
.acc-q::-webkit-details-marker { display:none; }
.acc-chevron { transition:transform .2s; color:var(--on-surface-variant); }
.acc-item[open] .acc-chevron { transform:rotate(180deg); }
.acc-a { padding:0 18px 18px; font-size:.92rem; line-height:1.6; color:var(--on-surface-variant); }

/* ---- Comparison ---- */
.cmp-table th,.cmp-table td { padding:14px 16px; text-align:center; border-bottom:1px solid var(--outline-variant); color:var(--on-surface); }
.cmp-table thead th { vertical-align:bottom; }
.cmp-feat { text-align:left !important; font-weight:600; color:var(--on-surface-variant); }
.cmp-plan { font-weight:700; font-size:1.05rem; }
.cmp-price { color:var(--primary); font-weight:600; }
.cmp-note { font-size:.78rem; color:var(--on-surface-variant); }
.cmp-col--hl { background:var(--secondary-container); }
.cmp-yes { color:var(--success); }
.cmp-no { color:var(--outline); }

/* ---- Leaderboard ---- */
.seg { display:inline-flex; gap:4px; background:var(--surface-container-high); border-radius:var(--radius-lg); padding:4px; margin-bottom:18px; }
.seg__btn { border:none; background:transparent; color:var(--on-surface-variant); padding:8px 18px; border-radius:var(--radius-lg); cursor:pointer; font:inherit; font-weight:500; }
.seg__btn--active { background:var(--primary); color:var(--on-primary); }
.lb-list { list-style:none; margin:0 0 18px; padding:0; display:flex; flex-direction:column; gap:8px; }
.lb-row { display:grid; grid-template-columns:auto auto 1fr auto auto; align-items:center; gap:12px; background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:12px 16px; }
.lb-rank { font-variant-numeric:tabular-nums; font-weight:700; color:var(--on-surface-variant); min-width:1.5em; }
.lb-tier { font-weight:700; width:1.8em; height:1.8em; display:inline-grid; place-items:center; border-radius:50%; color:#fff; font-size:.8rem; }
.lb-tier--S { background:#B3261E; } .lb-tier--A { background:#7D5260; } .lb-tier--B { background:#6750A4; }
.lb-tier--C { background:#625B71; } .lb-tier--D { background:#79747E; }
.lb-name { font-weight:600; color:var(--on-surface); }
.lb-meta { font-size:.82rem; color:var(--on-surface-variant); }
.lb-score { font-weight:700; font-variant-numeric:tabular-nums; color:var(--primary); }
.lb-tier-group { margin-bottom:16px; }
.lb-tier-head { display:inline-grid; place-items:center; min-width:2em; height:2em; border-radius:var(--radius-sm); color:#fff; font-weight:700; padding:0 10px; margin-bottom:10px; }

/* ---- Scrolly ---- */
.scrolly { display:grid; grid-template-columns:1fr 1fr; gap:32px; align-items:start; }
.scrolly-sticky { position:sticky; top:120px; height:60vh; display:flex; }
.scrolly-visual { flex:1; display:flex; align-items:center; justify-content:center; background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius-lg); padding:24px; }
.scrolly-stat { font-size:2.4rem; font-weight:700; text-align:center; }
.scrolly-steps { display:flex; flex-direction:column; gap:60vh; padding:20vh 0; }
.scrolly-step { background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:20px 22px; opacity:.4; transition:opacity .3s; }
.scrolly-step p { margin:0; font-size:1.1rem; line-height:1.6; color:var(--on-surface); }
.scrolly-step--active { opacity:1; }

/* ---- Map ---- */
.map-layout { display:grid; grid-template-columns:1fr 300px; gap:18px; align-items:start; }
.map-box { height:460px; border-radius:var(--radius); overflow:hidden; border:1px solid var(--outline-variant); background:var(--surface-container); }
.map-fallback { height:100%; display:flex; align-items:center; justify-content:center; color:var(--on-surface-variant); padding:20px; text-align:center; }
.map-list { list-style:none; margin:0; padding:0; display:flex; flex-direction:column; gap:8px; max-height:460px; overflow:auto; }
.place { display:flex; flex-direction:column; gap:3px; background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius-sm); padding:12px 14px; cursor:pointer; }
.place:hover,.place:focus-visible { border-color:var(--primary); outline:none; }
.place b { color:var(--on-surface); }
.place span { font-size:.82rem; color:var(--on-surface-variant); }

/* ---- Dialog ---- */
.dialog { border:none; border-radius:var(--radius-lg); background:var(--surface-container-high); color:var(--on-surface); max-width:600px; width:calc(100% - 32px); padding:0; box-shadow:var(--elev-3); }
.dialog::backdrop { background:rgba(0,0,0,.5); }
.dialog__bar { display:flex; align-items:center; padding:8px 12px; border-bottom:1px solid var(--outline-variant); position:sticky; top:0; background:var(--surface-container-high); }
.dialog__spacer { flex:1; }
.dialog__body { padding:24px; }
.dialog__body h2 { margin-top:0; color:var(--on-surface); }
.dialog__body p { color:var(--on-surface-variant); line-height:1.65; }
.dialog__body .card__tags { margin:0 0 14px; }

/* ---- Footer ---- */
.footer { text-align:center; padding:32px 16px; margin-top:32px; color:var(--on-surface-variant); font-size:.85rem; border-top:1px solid var(--outline-variant); }

/* ---- Responsive ---- */
@media (max-width:860px) {
  .article-layout { grid-template-columns:1fr; }
  .toc { position:static; }
  .toc__inner { flex-direction:row; flex-wrap:wrap; border-left:none; }
  .scrolly { grid-template-columns:1fr; }
  .scrolly-sticky { position:sticky; top:64px; height:auto; }
  .scrolly-steps { gap:30vh; padding:10vh 0; }
  .map-layout { grid-template-columns:1fr; }
  .map-list { flex-direction:row; max-height:none; }
  .bento { grid-template-columns:repeat(2,1fr); }
  .tile--lg,.tile--wide,.tile--md { grid-column:span 2; }
}
@media (max-width:600px) {
  .grid { grid-template-columns:1fr; }
  .bento { grid-template-columns:1fr; }
  .tile--lg,.tile--wide,.tile--md,.tile--tall { grid-column:span 1; grid-row:span 1; }
  .lb-row { grid-template-columns:auto auto 1fr auto; }
  .lb-meta { display:none; }
  .icon-btn__txt { font-size:.8rem; }
}
@media (max-width:375px) {
  .appbar__inner,.pagenav__inner,.page { padding-left:12px; padding-right:12px; }
  .page-head h1 { font-size:1.4rem; }
}

/* Respect reduced motion */
@media (prefers-reduced-motion:reduce) {
  html { scroll-behavior:auto; }
  * { transition:none !important; }
}

/* =======================================================================
   AI 治理百科 — 編輯極簡主題（覆蓋 MD3 基底）
   暖色單色畫布 · slate-ink 強調色 · 襯線標題 · 極細邊框 · 無漸層重陰影
   ===================================================================== */

/* ---- tokens : light ---- */
:root, [data-theme="light"] {
  --primary:#355070; --on-primary:#FFFFFF;
  --primary-container:#DCE6EF; --on-primary-container:#1F3850;
  --secondary:#6A6962; --secondary-container:#EBE8E0; --on-secondary-container:#3A372F;
  --tertiary:#7A5C3E; --tertiary-container:#EFE6DA;
  --background:#F7F6F3; --on-background:#20242A;
  --surface:#FFFFFF;
  --surface-container:#FFFFFF; --surface-container-high:#F1EFEA; --surface-variant:#EEEBE5;
  --on-surface:#20242A; --on-surface-variant:#6A6962;
  --outline:#C5C1B8; --outline-variant:#E5E2DB;
  --error:#9F2F2D; --success:#346538;
  --elev-1:0 1px 2px rgba(20,20,15,.04);
  --elev-2:0 2px 10px rgba(20,20,15,.06);
  --elev-3:0 10px 30px rgba(20,20,15,.12);
  --radius-sm:6px; --radius:10px; --radius-lg:12px;
  --font-body:"Noto Sans TC",-apple-system,BlinkMacSystemFont,"Segoe UI","Helvetica Neue",sans-serif;
  --font-serif:"Noto Serif TC","Newsreader",Georgia,"Times New Roman",serif;
  --font-mono:"Noto Sans Mono","SF Mono",ui-monospace,monospace;
}
/* ---- tokens : dark ---- */
[data-theme="dark"] {
  --primary:#92B3CF; --on-primary:#0E2233;
  --primary-container:#2A3C4E; --on-primary-container:#CFE0EE;
  --secondary:#A8A69E; --secondary-container:#2C2A25; --on-secondary-container:#E7E3DB;
  --tertiary:#C9A883; --tertiary-container:#3A2F22;
  --background:#15171B; --on-background:#E7E3DB;
  --surface:#1B1E22;
  --surface-container:#1C1F24; --surface-container-high:#23272D; --surface-variant:#2A2E34;
  --on-surface:#E7E3DB; --on-surface-variant:#A8A69E;
  --outline:#4C5057; --outline-variant:#31353B;
  --error:#E5928F; --success:#9FC8A3;
}

/* ---- editorial typography ---- */
body { font-family:var(--font-body); letter-spacing:.003em; }
.page-head h1, .prose h2, .dialog__body h2 {
  font-family:var(--font-serif); font-weight:600; letter-spacing:-.005em;
}
.page-head h1 { font-size:clamp(1.7rem,4.2vw,2.4rem); line-height:1.2; }
.prose h2 { font-size:1.45rem; line-height:1.3; }
.prose h3 { font-weight:600; }
.brand__name { font-family:var(--font-serif); font-weight:600; }
.tl-date, .quiz-n, .hero__stat-value, .stat-value { font-family:var(--font-mono); font-variant-numeric:tabular-nums; }

/* ---- flatten surfaces : thin borders, whisper shadows ---- */
.appbar { box-shadow:none; border-bottom:1px solid var(--outline-variant);
  background:color-mix(in srgb,var(--surface) 88%,transparent); backdrop-filter:saturate(120%) blur(8px); }
.card, .hero__stat, .stat-card, .panel, .tl-card, .acc-item, .kb-card, .tile, .gl-item, .quiz-card { box-shadow:none; }
.card { border:1px solid var(--outline-variant); }
.card:hover, .card:focus-visible { box-shadow:var(--elev-2); transform:translateY(-2px); border-color:var(--outline); }
.tile--accent { background:var(--primary-container); border-color:transparent; }
.navpill--active { background:var(--secondary-container); color:var(--on-secondary-container); }
.chip--active { background:var(--on-surface); color:var(--surface); border-color:transparent; }
.tl-dot { box-shadow:0 0 0 2px var(--primary); }

/* ---- glossary ---- */
.glossary-list { display:grid; grid-template-columns:repeat(auto-fill,minmax(330px,1fr)); gap:12px; }
.gl-item { background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:14px 16px; }
.gl-term { display:flex; align-items:baseline; justify-content:space-between; gap:10px;
  font-weight:600; color:var(--on-surface); font-size:.98rem; line-height:1.4; margin-bottom:6px; }
.gl-cat { flex:0 0 auto; font-size:.66rem; letter-spacing:.03em; padding:2px 9px; border-radius:999px; white-space:nowrap; }
.gl-def { font-size:.86rem; line-height:1.6; color:var(--on-surface-variant); }
.gl-cat--law{background:#E1F0FB;color:#1F5E86;} .gl-cat--standard{background:#E9E5F6;color:#4B3B86;}
.gl-cat--org{background:#FAF0DA;color:#876200;} .gl-cat--ethics{background:#FBE7E6;color:#9F2F2D;}
.gl-cat--tech{background:#E4F1E7;color:#2F6A3C;} .gl-cat--concept{background:#ECEAE4;color:#59564D;}
.gl-cat--ipbiz{background:#FAE7DD;color:#9A4E2A;}
[data-theme="dark"] .gl-cat--law{background:#173a50;color:#9fc7e6;} [data-theme="dark"] .gl-cat--standard{background:#2c2848;color:#c3b8e8;}
[data-theme="dark"] .gl-cat--org{background:#43340f;color:#e6c589;} [data-theme="dark"] .gl-cat--ethics{background:#48201f;color:#e8a9a7;}
[data-theme="dark"] .gl-cat--tech{background:#1f3a26;color:#a6d6ae;} [data-theme="dark"] .gl-cat--concept{background:#2d2b26;color:#bdb9ae;}
[data-theme="dark"] .gl-cat--ipbiz{background:#3e2418;color:#e0b59c;}

/* ---- quiz ---- */
.quiz-score { font-size:.82rem; color:var(--on-surface-variant); margin:0 0 16px; padding:10px 0;
  border-bottom:1px solid var(--outline-variant); position:sticky; top:104px; background:var(--background); z-index:5; }
.quiz { display:flex; flex-direction:column; gap:16px; max-width:760px; }
.quiz-card { background:var(--surface-container); border:1px solid var(--outline-variant); border-radius:var(--radius); padding:18px 20px; }
.quiz-q { display:flex; gap:10px; align-items:baseline; font-weight:600; color:var(--on-surface); margin:0 0 14px; line-height:1.55; }
.quiz-n { flex:0 0 auto; display:inline-grid; place-items:center; min-width:1.7em; height:1.7em; border-radius:50%;
  background:var(--primary-container); color:var(--on-primary-container); font-size:.76rem; }
.quiz-opts { display:grid; gap:8px; }
.quiz-opt { text-align:left; padding:11px 14px; border:1px solid var(--outline-variant); border-radius:var(--radius-sm);
  background:var(--surface); color:var(--on-surface); font:inherit; cursor:pointer; transition:background .12s,border-color .12s; }
.quiz-opt:hover:not(:disabled) { background:var(--surface-container-high); border-color:var(--outline); }
.quiz-opt:disabled { cursor:default; }
.quiz-opt--correct { background:#EDF6EE; border-color:#9CCBA3; color:#2A5D33; font-weight:600; }
.quiz-opt--wrong { background:#FBEAEA; border-color:#E0A3A1; color:#9F2F2D; }
[data-theme="dark"] .quiz-opt--correct { background:#1E3A24; border-color:#3f6e47; color:#A9D6B0; }
[data-theme="dark"] .quiz-opt--wrong { background:#3E2020; border-color:#7a3f3d; color:#E6A9A7; }
.quiz-explain { margin-top:12px; padding:11px 14px; border-left:3px solid var(--primary);
  background:var(--surface-container-high); border-radius:0 var(--radius-sm) var(--radius-sm) 0;
  font-size:.86rem; line-height:1.65; color:var(--on-surface-variant); }

/* ---- flashcards ---- */
.flashgrid { display:grid; grid-template-columns:repeat(auto-fill,minmax(220px,1fr)); gap:14px; }
.flashcard { perspective:1200px; height:180px; cursor:pointer; }
.flashcard:focus-visible { outline:2px solid var(--primary); outline-offset:3px; border-radius:var(--radius); }
.flashcard__inner { position:relative; width:100%; height:100%; transform-style:preserve-3d;
  transition:transform .5s cubic-bezier(.2,.7,.2,1); }
.flashcard.flipped .flashcard__inner { transform:rotateY(180deg); }
.flashcard__face { position:absolute; inset:0; backface-visibility:hidden; -webkit-backface-visibility:hidden;
  display:flex; align-items:center; justify-content:center; text-align:center; padding:18px;
  border:1px solid var(--outline-variant); border-radius:var(--radius); overflow:auto; }
.flashcard__front { background:var(--surface-container); color:var(--on-surface); font-weight:600; font-size:1.02rem; font-family:var(--font-serif); }
.flashcard__back { background:var(--primary-container); color:var(--on-primary-container); transform:rotateY(180deg); font-size:.85rem; line-height:1.6; }

/* ---- source links (timeline cards + gallery dialog) ---- */
.tl-src { display:inline-block; margin-top:8px; font-size:.74rem; font-family:var(--font-mono); color:var(--primary); }
.tl-src:hover { text-decoration:underline; }
.dialog__src { margin-top:16px; padding-top:12px; border-top:1px solid var(--outline-variant); }
.dialog__body p { line-height:1.7; }

/* ---- reference lists (article footer + gallery dialog) ---- */
.ref-head { margin:0 0 8px; font-size:.78rem; font-weight:700; letter-spacing:.08em;
  text-transform:uppercase; color:var(--on-surface-variant); font-family:var(--font-mono); }
.ref-list { list-style:none; margin:0; padding:0; display:flex; flex-direction:column; gap:7px; }
.ref-list li { position:relative; padding-left:16px; }
.ref-list li::before { content:"›"; position:absolute; left:2px; top:0; color:var(--outline); }
.ref-link { font-size:.85rem; line-height:1.5; color:var(--primary); word-break:break-word; }
.ref-link:hover { text-decoration:underline; }
.prose .article-section:last-child .ref-list { margin-top:4px; }

/* ---- GitHub star button (appbar) ---- */
.gh-star { display:inline-flex; align-items:center; gap:6px; padding:6px 11px;
  border:1px solid var(--outline-variant); border-radius:var(--radius-lg);
  color:var(--on-surface-variant); font-size:.82rem; font-weight:500;
  transition:background .15s,border-color .15s,color .15s; }
.gh-star:hover { background:var(--surface-container-high); border-color:var(--outline); color:var(--on-surface); }
.gh-star .material-symbols-rounded { font-size:18px; color:#E3B341; }
.gh-star__count { font-family:var(--font-mono); font-variant-numeric:tabular-nums; min-width:1ch; }

/* ---- responsive : sticky offsets for the quiz score on small screens ---- */
@media (max-width:860px){ .quiz-score{ top:60px; } }
@media (max-width:600px){
  .glossary-list{ grid-template-columns:1fr; }
  .flashgrid{ grid-template-columns:repeat(auto-fill,minmax(150px,1fr)); }
}
@media (max-width:375px){ .gh-star__count{ display:none; } }