/* ===== BLANC project page ===== */
:root {
  --bg: #f7f8fb;
  --bg-soft: #eef1f7;
  --card: #ffffff;
  --border: #e2e6ee;
  --fg: #161b26;
  --fg-soft: #5a6475;
  --accent: #4357d6;      /* body / indigo */
  --accent-2: #12a38a;    /* adaptive blocks / teal */
  --hl: #dbe4ff;          /* table highlight, matches paper */
  --max-w: 1040px;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(16,24,40,.04), 0 6px 24px rgba(16,24,40,.06);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f131a; --bg-soft: #171c25; --card: #151a22; --border: #262d3a;
    --fg: #e7eaf0; --fg-soft: #9aa4b5; --accent: #8193ff; --accent-2: #3fd1b4;
    --hl: rgba(129,147,255,.16); --shadow: none;
  }
}
:root[data-theme="dark"] {
  --bg: #0f131a; --bg-soft: #171c25; --card: #151a22; --border: #262d3a;
  --fg: #e7eaf0; --fg-soft: #9aa4b5; --accent: #8193ff; --accent-2: #3fd1b4;
  --hl: rgba(129,147,255,.16); --shadow: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 72px; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: "Inter", system-ui, -apple-system, "Noto Sans", sans-serif;
  line-height: 1.65; -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
code { background: var(--bg-soft); padding: 1px 6px; border-radius: 6px; font-size: .88em; }
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 16px; }
.sc { font-variant: small-caps; letter-spacing: .02em; }

/* nav */
nav.topnav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(10px); border-bottom: 1px solid var(--border);
}
nav.topnav .container { display: flex; align-items: center; gap: 16px; height: 56px; }
nav.topnav .links { margin-left: auto; }
.brand {
  font-weight: 800; letter-spacing: .08em;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
nav .links a { color: var(--fg-soft); margin-left: 20px; font-size: .92rem; font-weight: 500; }
nav .links a:hover { color: var(--fg); text-decoration: none; }
@media (max-width: 720px) { nav .links a { margin-left: 12px; font-size: .8rem; } }
@media (max-width: 560px) { nav .links { display: none; } .theme-toggle { margin-left: auto; } }

/* hero */
header.hero { padding: 60px 0 28px; text-align: center; }
.hero h1 { font-size: 2.3rem; line-height: 1.2; margin: 0 0 10px; font-weight: 800; }
.hero h1 .name {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero .subtitle { font-size: 1.25rem; font-weight: 600; color: var(--fg); margin: 0 0 14px; }
@media (max-width: 640px) { .hero h1 { font-size: 1.75rem; } .hero .subtitle { font-size: 1.05rem; } }
.venue { color: var(--fg-soft); font-weight: 600; letter-spacing: .05em; margin-bottom: 18px; }
.authors { font-size: 1.06rem; line-height: 1.9; }
.authors a { color: var(--fg); }
.authors a:hover { color: var(--accent); }
.affil { color: var(--fg-soft); margin-top: 4px; }
.corr { color: var(--fg-soft); font-size: .88rem; margin-top: 4px; }
.btn-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-top: 24px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 9px 18px;
  border-radius: 999px; background: var(--fg); color: var(--bg);
  font-weight: 600; font-size: .94rem; transition: transform .15s, opacity .15s;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); opacity: .9; }
.btn svg { width: 17px; height: 17px; fill: currentColor; }
.btn.disabled { opacity: .45; pointer-events: none; }
.btn .hf { font-size: 1.05rem; line-height: 1; }

/* sections */
section { padding: 44px 0; border-top: 1px solid var(--border); }
section h2 { font-size: 1.6rem; text-align: center; margin: 0 0 22px; }
section h3 { font-size: 1.15rem; margin: 30px 0 10px; }
p { margin: 0 0 14px; }
.lead { color: var(--fg-soft); text-align: center; max-width: 780px; margin: -8px auto 26px; }

.tldr {
  display: flex; gap: 14px; align-items: flex-start;
  background: var(--card); border: 1px solid var(--border); border-left: 4px solid var(--accent-2);
  border-radius: var(--radius); padding: 18px 22px; box-shadow: var(--shadow);
}
.tldr-badge {
  flex: none; font-weight: 800; font-size: .78rem; letter-spacing: .08em;
  color: #fff; background: var(--accent-2); padding: 3px 10px; border-radius: 999px; margin-top: 3px;
}
.tldr p { margin: 0; }

.abstract p { text-align: justify; hyphens: auto; }

figure { margin: 0 0 8px; }
.fig {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 14px; box-shadow: var(--shadow);
}
.fig img, .fig video { width: 100%; height: auto; display: block; border-radius: 6px; }
figcaption { color: var(--fg-soft); font-size: .92rem; margin-top: 10px; text-align: center; }
figcaption b { color: var(--fg); }
.narrow { max-width: 720px; margin-left: auto; margin-right: auto; }

/* challenge / contribution cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; margin-top: 8px; }
.card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; box-shadow: var(--shadow);
}
.cards.cols-2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 720px) { .cards.cols-2 { grid-template-columns: 1fr; } }
.card .k { font-size: .78rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--accent); }
.card.teal .k { color: var(--accent-2); }
.card h4 { margin: 6px 0 8px; font-size: 1.05rem; }
.card p { margin: 0; color: var(--fg-soft); font-size: .95rem; }

/* stat row */
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 14px; margin: 22px 0 6px; }
.stat { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; text-align: center; }
.stat .v { font-size: 1.6rem; font-weight: 800; color: var(--accent); }
.stat .l { font-size: .85rem; color: var(--fg-soft); }

/* tables */
.table-wrap { overflow-x: auto; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); }
table { border-collapse: collapse; width: 100%; font-size: .9rem; font-variant-numeric: tabular-nums; }
th, td { padding: 8px 10px; text-align: center; white-space: nowrap; }
th:first-child, td:first-child { text-align: left; }
thead th { font-weight: 600; border-bottom: 1px solid var(--border); }
thead tr.group th { color: var(--fg-soft); font-weight: 700; font-size: .82rem; }
tbody tr + tr td { border-top: 1px solid var(--border); }
tr.ours td { background: var(--hl); font-weight: 500; }
td.best, tr.ours td.best { font-weight: 800; }
td.second { text-decoration: underline; text-underline-offset: 3px; }
.tnote { color: var(--fg-soft); font-size: .85rem; margin-top: 8px; text-align: center; }

.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; align-items: start; }
@media (max-width: 820px) { .two-col { grid-template-columns: 1fr; } }

/* tabs for qualitative */
.tabs { display: flex; justify-content: center; gap: 8px; margin-bottom: 14px; flex-wrap: wrap; }
.tab {
  border: 1px solid var(--border); background: var(--card); color: var(--fg-soft);
  padding: 7px 16px; border-radius: 999px; font: inherit; font-size: .9rem; font-weight: 600; cursor: pointer;
}
.tab[aria-selected="true"] { background: var(--fg); color: var(--bg); border-color: var(--fg); }
.tab-panel[hidden] { display: none; }

/* placeholder for videos */
.placeholder {
  border: 2px dashed var(--border); border-radius: var(--radius); padding: 40px 20px;
  text-align: center; color: var(--fg-soft); background: var(--bg-soft);
}

/* bibtex */
.bib { position: relative; }
.bib pre {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px; overflow-x: auto; font-size: .85rem; line-height: 1.55; margin: 0;
}
.copy-btn {
  position: absolute; top: 10px; right: 10px; border: 1px solid var(--border); background: var(--card);
  color: var(--fg-soft); border-radius: 8px; padding: 4px 10px; font: inherit; font-size: .8rem; cursor: pointer;
}
.copy-btn:hover { color: var(--fg); }

footer { padding: 28px 0 40px; text-align: center; color: var(--fg-soft); font-size: .85rem; border-top: 1px solid var(--border); }

/* ===== video results gallery ===== */
.aff-sep { margin: 0 8px; }
.pills { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; margin: 0 0 16px; }
.pill {
  background: var(--card); border: 1px solid var(--border); color: var(--fg-soft);
  padding: 7px 18px; border-radius: 999px; font: inherit; font-weight: 600; font-size: .9rem;
  cursor: pointer; transition: .15s;
}
.pill:hover { color: var(--fg); border-color: var(--accent); }
.pill.active { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; border-color: transparent; }
.prompt-line { text-align: center; font-style: italic; max-width: 820px; margin: 0 auto 4px; min-height: 1.6em; }
.prompt-sub { text-align: center; color: var(--fg-soft); font-size: .9rem; margin: 0 auto 20px; min-height: 1.4em; }
.method-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
@media (max-width: 900px) { .method-grid { grid-template-columns: repeat(2, 1fr); } }
.method-cell { position: relative; margin: 0; }
.method-cell video {
  width: 100%; aspect-ratio: 492 / 554; object-fit: cover; display: block;
  background: #fff; border: 1px solid var(--border); border-radius: 12px;
}
.method-cell.ours video { border-color: var(--accent); box-shadow: 0 0 0 2px color-mix(in srgb, var(--accent) 40%, transparent); }
.tag {
  position: absolute; top: 8px; left: 8px; z-index: 2;
  padding: 2px 9px; border-radius: 6px; font-size: .78rem; font-weight: 700;
  background: rgba(22,27,38,.78); color: #fff;
}
.tag.ref { background: rgba(18,163,138,.9); }
.tag.ours { background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
.chip { display: inline-block; padding: 1px 8px; border-radius: 6px; font-weight: 700; font-size: .8rem; }
.chip.ours { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; }
.note { text-align: center; color: var(--fg-soft); font-size: .88rem; margin-top: 14px; }

/* ===== theme toggle ===== */
.theme-toggle {
  flex: none; width: 36px; height: 36px; display: inline-grid; place-items: center;
  border: 1px solid var(--border); border-radius: 999px; background: var(--card);
  color: var(--fg-soft); cursor: pointer; transition: color .15s, border-color .15s;
}
.theme-toggle:hover { color: var(--fg); border-color: var(--accent); }
.theme-toggle svg { width: 18px; height: 18px; fill: currentColor; }
.theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: block; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: none; }
}
body, nav.topnav, .card, .stat, .table-wrap, .tldr { transition: background-color .2s, color .2s, border-color .2s; }

/* ===== headline stat row ===== */
section.headline { border-top: none; padding: 8px 0 34px; }
.stats-4 { grid-template-columns: repeat(4, 1fr); margin: 0; }
@media (max-width: 860px) { .stats-4 { grid-template-columns: repeat(2, 1fr); } }
.stat .l { line-height: 1.4; }
.stat .s { font-size: .78rem; color: var(--fg-soft); opacity: .8; margin-top: 6px; font-variant-numeric: tabular-nums; }

/* ===== video play / pause ===== */
.video-controls { display: flex; align-items: center; justify-content: center; gap: 14px; flex-wrap: wrap; margin-top: 14px; }
.video-controls .note { margin: 0; }
.play-toggle {
  display: inline-flex; align-items: center; gap: 6px;
  border: 1px solid var(--border); background: var(--card); color: var(--fg);
  padding: 6px 14px; border-radius: 999px; font: inherit; font-size: .88rem; font-weight: 600; cursor: pointer;
}
.play-toggle:hover { border-color: var(--accent); }
.play-toggle svg { width: 15px; height: 15px; fill: currentColor; }
.play-toggle .icon-play { display: none; }
.play-toggle[aria-pressed="true"] .icon-play { display: block; }
.play-toggle[aria-pressed="true"] .icon-pause { display: none; }

/* ===== videos as the above-the-fold teaser ===== */
header.hero { padding: 40px 0 20px; }
section.teaser-videos { border-top: none; padding: 8px 0 28px; }
.teaser-videos .pills { margin-bottom: 10px; }
.teaser-videos .prompt-sub { margin-bottom: 14px; }