/* ==========================================================
   VNCultureVQA project page – theme on top of Bulma
   ========================================================== */

:root {
  --red: #b3261e;
  --red-dark: #8c1d18;
  --red-soft: #fbe9e7;
  --gold: #c8961e;
  --gold-soft: #f6ebcd;
  --ink: #1f1a17;
  --ink-2: #4d4540;
  --muted: #7a716a;
  --paper: #fbf7f0;
  --surface: #fffdf9;
  --line: rgba(31, 26, 23, 0.10);
  --line-strong: rgba(31, 26, 23, 0.18);
  --radius: 14px;
  --shadow: 0 1px 2px rgba(31, 26, 23, 0.04), 0 8px 24px rgba(31, 26, 23, 0.06);

  /* Ordinal red ramp: context levels L1→L3 and difficulty groups (validated) */
  --ord-1: #eb9a8f;
  --ord-2: #d2493d;
  --ord-3: #8c1d18;
  /* Single-series bars */
  --single: #c8961e;

  --font-head: 'Be Vietnam Pro', 'Noto Sans', system-ui, sans-serif;
  --font-body: 'Noto Sans', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

html { scroll-behavior: smooth; scroll-padding-top: 4.5rem; background: var(--paper); }
body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  overflow-x: hidden;
}

h1, h2, h3, h4, .title, .subtitle { font-family: var(--font-head); color: var(--ink); }
a { color: var(--red); }
a:hover { color: var(--red-dark); }
.content p { color: var(--ink-2); }
.content strong, strong { color: var(--ink); }
.mono { font-family: var(--font-mono); }
.brand-name { font-family: var(--font-head); font-weight: 800; color: var(--red); letter-spacing: -0.01em; }

/* ---------- Navbar ---------- */
.navbar.site-nav {
  position: sticky; top: 0; z-index: 40;
  background: rgba(251, 247, 240, 0.88);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-nav .navbar-item, .site-nav .navbar-link {
  font-family: var(--font-head); font-weight: 500; color: var(--ink-2); font-size: 0.95rem;
}
.site-nav a.navbar-item:hover, .site-nav a.navbar-item.is-active {
  background: transparent; color: var(--red);
}
.site-nav .navbar-brand .navbar-item { font-weight: 800; color: var(--red); font-size: 1.1rem; }
.site-nav .navbar-burger span { background-color: var(--ink); }
.site-nav .navbar-menu.is-active { background: var(--paper); box-shadow: var(--shadow); }

/* ---------- Hero ---------- */
.hero.site-hero { position: relative; background: var(--paper); overflow: hidden; }
.site-hero::before {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 6px;
  background: linear-gradient(90deg, var(--red) 0%, var(--red) 60%, var(--gold) 60%, var(--gold) 100%);
}
.site-hero::after {
  /* faint lotus-like radial ornament */
  content: ""; position: absolute; width: 640px; height: 640px; right: -220px; top: -260px;
  background: radial-gradient(circle, rgba(200, 150, 30, 0.14) 0%, rgba(200, 150, 30, 0) 65%);
  pointer-events: none;
}
.site-hero .hero-body { padding-top: 4.5rem; padding-bottom: 2.5rem; position: relative; z-index: 1; }
.publication-title {
  font-family: var(--font-head); font-weight: 800; line-height: 1.15 !important;
  letter-spacing: -0.02em; font-size: clamp(2rem, 4.6vw, 3.25rem) !important;
}
.publication-title .brand-name { display: block; font-size: 1.12em; margin-bottom: 0.2rem; }
.publication-authors { font-family: var(--font-head); color: var(--ink-2); }
.publication-authors a { color: var(--ink) !important; border-bottom: 1px dashed var(--line-strong); }
.publication-authors a:hover { color: var(--red) !important; border-bottom-color: var(--red); }
.author-block { display: inline-block; margin: 0 0.4rem; }
.affiliations { font-size: 1rem; color: var(--muted); }
.affiliations .author-block { margin: 0 0.6rem; }
.contrib-note { font-size: 0.85rem; color: var(--muted); margin-top: 0.35rem; }

.publication-links { margin-top: 1.5rem; display: flex; flex-wrap: wrap; justify-content: center; gap: 0.6rem; }
.publication-links .button {
  font-family: var(--font-head); font-weight: 600;
  background: var(--ink); color: #fff; border: none; border-radius: 999px;
  padding-left: 1.15rem; padding-right: 1.15rem; transition: background 0.15s, transform 0.15s;
}
.publication-links .button:hover { background: var(--red); color: #fff; transform: translateY(-1px); }
.publication-links .button .icon { margin-right: 0.25rem !important; }

/* Placeholder marker for content the authors still need to supply */
.todo {
  display: inline-block; font-family: var(--font-mono); font-size: 0.68rem; font-weight: 700;
  letter-spacing: 0.04em; color: var(--red-dark); background: var(--gold-soft);
  border: 1px dashed var(--gold); border-radius: 6px; padding: 0 0.35rem; margin-left: 0.35rem;
  vertical-align: middle; line-height: 1.5;
}
.publication-links .button .todo { color: var(--ink); margin-left: 0.4rem; }
/* ---------- Hero gallery (mosaic) ---------- */
.mosaic-band { padding: 0 1.5rem 2.5rem; }
.mosaic {
  display: grid; grid-template-columns: repeat(10, minmax(0, 1fr)); gap: 4px;
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 6px; box-shadow: var(--shadow);
}
.mosaic .tile {
  position: relative; aspect-ratio: 4 / 3; overflow: hidden; border-radius: 4px;
  background: rgba(31, 26, 23, 0.05);
}
.mosaic .tile img {
  display: block; width: 100%; height: 100%; object-fit: cover; cursor: zoom-in;
  transition: transform 0.25s ease;
}
.mosaic .tile:hover img { transform: scale(1.06); }
.mosaic .tile.is-empty {
  display: flex; align-items: center; justify-content: center; color: rgba(31, 26, 23, 0.22);
  background: repeating-linear-gradient(45deg, rgba(200, 150, 30, 0.08) 0 6px, transparent 6px 12px), var(--paper);
  font-size: 0.9rem;
}
.mosaic-caption {
  text-align: center; font-size: 0.88rem; font-style: italic; color: var(--muted); margin-top: 0.75rem;
}
.mosaic-caption b { color: var(--ink-2); font-style: normal; }
/* ---------- Figures ---------- */
figure.paper-figure { margin: 0; }
figure.paper-figure img {
  display: block; width: 100%; height: auto; border-radius: 10px; cursor: zoom-in;
  background: #fff;
}
figure.paper-figure.framed {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem;
}
figure.paper-figure figcaption, .chart-caption {
  font-size: 0.9rem; color: var(--muted); margin-top: 0.75rem; line-height: 1.5;
}
figure.paper-figure figcaption b, .chart-caption b { color: var(--ink-2); font-family: var(--font-head); }

/* ---------- Stat cards ---------- */
.stats-band { padding: 1rem 1.5rem 3rem; }
.stat-grid {
  display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 1rem;
}
.stat-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.1rem 1rem; text-align: center; box-shadow: var(--shadow); position: relative; overflow: hidden;
}
.stat-card::before {
  content: ""; position: absolute; left: 0; right: 0; top: 0; height: 3px; background: var(--red);
}
.stat-card:nth-child(even)::before { background: var(--gold); }
.stat-value {
  font-family: var(--font-head); font-weight: 800; font-size: clamp(1.5rem, 2.6vw, 2.1rem);
  color: var(--ink); line-height: 1.1;
}
.stat-label { font-size: 0.85rem; color: var(--muted); margin-top: 0.35rem; }

/* ---------- Sections ---------- */
.section { padding: 4rem 1.5rem; }
.section.alt { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { text-align: center; margin-bottom: 2.25rem; }
.section-kicker {
  font-family: var(--font-head); font-size: 0.8rem; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--red); margin-bottom: 0.4rem;
}
.section-head .title { font-weight: 800; letter-spacing: -0.015em; margin-bottom: 0.6rem !important; }
.section-head .lead { color: var(--ink-2); max-width: 720px; margin: 0 auto; }
.sub-title {
  font-family: var(--font-head); font-weight: 700; font-size: 1.3rem; margin: 2.75rem 0 1rem;
  display: flex; align-items: center; gap: 0.6rem;
}
.sub-title::before {
  content: ""; width: 10px; height: 10px; border-radius: 3px; background: var(--red);
  transform: rotate(45deg); flex: none;
}

/* ---------- Generic cards ---------- */
.card-plain {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.35rem 1.4rem; height: 100%; box-shadow: var(--shadow);
}
.section.alt .card-plain { background: var(--paper); box-shadow: none; }
.card-plain h4 { font-weight: 700; font-size: 1.05rem; margin-bottom: 0.4rem; }
.card-plain p { color: var(--ink-2); font-size: 0.95rem; }
.icon-chip {
  width: 2.6rem; height: 2.6rem; border-radius: 12px; display: inline-flex; align-items: center;
  justify-content: center; background: var(--red-soft); color: var(--red); font-size: 1.1rem; margin-bottom: 0.8rem;
}
.icon-chip.gold { background: var(--gold-soft); color: #8a6512; }

/* ---------- Taxonomy ---------- */
.tax-card { border-top: 4px solid var(--ord-1); }
.tax-card.g1 { border-top-color: var(--ord-2); }
.tax-card.g2 { border-top-color: var(--ord-3); }
.tax-share { font-family: var(--font-head); font-weight: 800; font-size: 1.9rem; line-height: 1; }
.tax-share small { font-size: 0.85rem; font-weight: 500; color: var(--muted); margin-left: 0.25rem; }
.level-row { display: flex; align-items: center; gap: 0.6rem; margin-top: 0.85rem; }
.level-id {
  flex: none; font-family: var(--font-mono); font-weight: 700; font-size: 0.78rem; color: var(--ink);
  background: rgba(31, 26, 23, 0.06); border-radius: 6px; padding: 0.1rem 0.4rem;
}
.level-name { flex: 1; font-size: 0.9rem; color: var(--ink-2); line-height: 1.3; }
.level-pct { flex: none; font-family: var(--font-head); font-weight: 700; font-size: 0.9rem; font-variant-numeric: tabular-nums; }
.level-bar { height: 6px; border-radius: 3px; background: rgba(31, 26, 23, 0.07); margin-top: 0.3rem; overflow: hidden; }
.level-bar > span { display: block; height: 100%; border-radius: 3px; background: var(--ord-1); }
.g1 .level-bar > span { background: var(--ord-2); }
.g2 .level-bar > span { background: var(--ord-3); }
.formula-box {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1rem 1.25rem; text-align: center; overflow-x: auto;
}
.section.alt .formula-box { background: var(--paper); }

/* ---------- Tabs (Bulma override) ---------- */
.tabs.vn-tabs ul { border-bottom-color: var(--line); }
.tabs.vn-tabs a {
  font-family: var(--font-head); font-weight: 600; color: var(--muted); border-bottom-width: 2px;
}
.tabs.vn-tabs a:hover { color: var(--ink); border-bottom-color: var(--line-strong); }
.tabs.vn-tabs li.is-active a { color: var(--red); border-bottom-color: var(--red); }
.tabs.is-toggle.vn-tabs a { border-color: var(--line-strong); background: var(--surface); }
.tabs.is-toggle.vn-tabs li.is-active a { background: var(--red); border-color: var(--red); color: #fff; }
.tab-pane { display: none; }
.tab-pane.is-active { display: block; animation: fadeIn 0.25s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }

/* ---------- Charts ---------- */
.chart-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.1rem 1.2rem 1rem; height: 100%; box-shadow: var(--shadow);
}
.chart-card h4 { font-family: var(--font-head); font-weight: 700; font-size: 1rem; margin-bottom: 0.15rem; }
.chart-card .chart-sub { font-size: 0.85rem; color: var(--muted); margin-bottom: 0.75rem; }
.chart-wrap { position: relative; height: 300px; }
.chart-wrap.tall { height: 360px; }

/* ---------- Example grid ---------- */
.example-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.1rem; }
.example-card {
  display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow);
}
.example-card .photo { aspect-ratio: 4 / 3; overflow: hidden; background: rgba(31, 26, 23, 0.05); }
.example-card .photo img { display: block; width: 100%; height: 100%; object-fit: cover; cursor: zoom-in; }
.example-card .qa { padding: 0.85rem 1rem 1rem; font-size: 0.9rem; line-height: 1.55; }
.example-card .qa p { margin: 0 0 0.45rem; color: var(--ink-2); }
.example-card .qa p:last-child { margin-bottom: 0; }
.example-card .qa .lbl {
  display: inline-block; min-width: 1.4rem; font-family: var(--font-head); font-weight: 700; color: var(--red);
}
.example-card .qa .q { color: var(--ink); font-weight: 500; }

/* ---------- Prose & formulas ---------- */
.prose { color: var(--ink-2); }
.prose p { color: var(--ink-2); }
.prose .katex-display { margin: 0.9rem 0 1.2rem; overflow-x: auto; overflow-y: hidden; padding: 0.2rem 0; }
.prose .katex { font-size: 1.08em; color: var(--ink); }

/* ---------- Tables ---------- */
.table-wrap {
  overflow-x: auto; -webkit-overflow-scrolling: touch; border: 1px solid var(--line);
  border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow);
}
.section.alt .table-wrap { box-shadow: none; }
table.vn-table {
  width: 100%; border-collapse: collapse; font-size: 0.9rem; font-variant-numeric: tabular-nums;
  background: transparent; margin: 0 !important;
}
table.vn-table th, table.vn-table td {
  padding: 0.55rem 0.75rem; border-bottom: 1px solid var(--line); white-space: nowrap; vertical-align: middle;
}
table.vn-table thead th {
  font-family: var(--font-head); font-weight: 700; color: var(--ink); background: rgba(31, 26, 23, 0.035);
  font-size: 0.82rem; text-align: center;
}
table.vn-table thead tr.group-row th { border-bottom: 1px solid var(--line); color: var(--muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; font-size: 0.72rem; }
table.vn-table td.num, table.vn-table th.num { text-align: right; }
table.vn-table td.center { text-align: center; }
table.vn-table tbody tr:last-child td { border-bottom: none; }
table.vn-table tbody tr:hover td { background: rgba(200, 150, 30, 0.06); }
table.vn-table tr.ours td { background: var(--red-soft); font-weight: 700; color: var(--ink); }
table.vn-table tr.total-row td { font-weight: 700; border-top: 2px solid var(--line-strong); }
table.vn-table td.model-cell { font-family: var(--font-head); font-weight: 600; vertical-align: top; }
table.vn-table tr.model-start td { border-top: 2px solid var(--line-strong); }
table.vn-table td.best { font-weight: 800; color: var(--red-dark); background: var(--gold-soft); }
table.vn-table td.second { text-decoration: underline; text-decoration-color: var(--gold); text-underline-offset: 3px; }
.table-note { font-size: 0.82rem; color: var(--muted); margin-top: 0.6rem; }
.lvl-pill {
  display: inline-block; font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700;
  padding: 0.05rem 0.45rem; border-radius: 6px; color: #fff;
}
.lvl-pill.L1 { background: var(--ord-1); color: var(--ink); }
.lvl-pill.L2 { background: var(--ord-2); }
.lvl-pill.L3 { background: var(--ord-3); }

/* ---------- Discussion (details) ---------- */
details.discuss {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.25rem;
}
details.discuss summary {
  cursor: pointer; font-family: var(--font-head); font-weight: 700; list-style: none;
  display: flex; align-items: center; justify-content: space-between;
}
details.discuss summary::-webkit-details-marker { display: none; }
details.discuss summary::after { content: "+"; font-size: 1.3rem; color: var(--red); }
details.discuss[open] summary::after { content: "–"; }
details.discuss .content { margin-top: 0.75rem; }

/* ---------- BibTeX ---------- */
.bibtex-box { position: relative; }
.bibtex-box pre {
  background: #1f1a17; color: #f6ebcd; border-radius: var(--radius); padding: 1.25rem 1.4rem;
  font-family: var(--font-mono); font-size: 0.85rem; line-height: 1.6; white-space: pre; overflow-x: auto;
}
.copy-btn {
  position: absolute; top: 0.75rem; right: 0.75rem; font-family: var(--font-head); font-weight: 600;
  font-size: 0.8rem; color: #1f1a17; background: var(--gold-soft); border: none; border-radius: 8px;
  padding: 0.3rem 0.7rem; cursor: pointer;
}
.copy-btn:hover { background: #fff; }

/* ---------- Footer ---------- */
.footer.site-footer { background: var(--ink); color: rgba(255, 255, 255, 0.72); padding: 2.5rem 1.5rem 3rem; }
.site-footer a { color: var(--gold-soft); }
.site-footer a:hover { color: #fff; }
.site-footer .icon-link { font-size: 1.4rem; margin: 0 0.6rem; color: #fff; }
.site-footer p { font-size: 0.85rem; }
.site-footer .footer-brand { font-family: var(--font-head); font-weight: 800; color: #fff; font-size: 1.2rem; }

/* ---------- Lightbox ---------- */
.lightbox {
  position: fixed; inset: 0; z-index: 100; background: rgba(20, 16, 14, 0.88); display: none;
  align-items: center; justify-content: center; padding: 2rem; cursor: zoom-out;
}
.lightbox.is-open { display: flex; }
.lightbox img { max-width: 100%; max-height: 100%; border-radius: 8px; background: #fff; }

/* ---------- Responsive ---------- */
@media screen and (max-width: 1023px) {
  .stat-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .example-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .mosaic { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}
@media screen and (max-width: 768px) {
  .section { padding: 3rem 1rem; }
  .stats-band { padding: 0.5rem 1rem 2.5rem; }
  .stat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat-grid .stat-card:last-child { grid-column: span 2; }
  .example-grid { grid-template-columns: 1fr; }
  .mosaic { grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 3px; padding: 4px; }
  .mosaic-band { padding: 0 1rem 2rem; }
  .site-hero .hero-body { padding: 3rem 1rem 1.75rem; }
  .chart-wrap { height: 260px; }
  .chart-wrap.tall { height: 320px; }
  .sub-title { font-size: 1.15rem; }
  .content.has-text-justified { text-align: left !important; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .tab-pane.is-active { animation: none; }
}