/* ==========================================================
   Brain2VLM project page
   Palette is taken from the project's own poster (navy field,
   cyan rule) and from the paper figures, where the linear
   baseline is boxed in red and our decoder in violet.
   ========================================================== */

:root {
  --bg: #ffffff;
  --bg-sunk: #f5f7fa;
  --panel: #ffffff;
  --text: #191c21;
  --text-soft: #565e6b;
  --rule: #dfe4ea;
  --rule-strong: #b9c2cd;

  --navy: #16365f;
  --navy-soft: #2b5c93;
  --cyan: #17a9c4;

  --linear: #c0392b;   /* ridge baseline, red box in the paper */
  --ours: #7d3cb5;     /* residual MLP, purple box in the paper */
  --gt: #3c4450;

  --zc: #2f6f9f;       /* diffusion latent z  */
  --cc: #d98e04;       /* CLIP embedding c    */

  --link: #1772d0;
  --link-hover: #f09228;
  --shadow: 0 1px 2px rgba(20, 34, 56, .08);

  --maxw: 940px;
  --wide: 1120px;
}

[data-theme="dark"] {
  --bg: #15171c;
  --bg-sunk: #1b1e24;
  --panel: #1b1e24;
  --text: #e3e5e8;
  --text-soft: #9aa3b0;
  --rule: #2c313a;
  --rule-strong: #414855;

  --navy: #9cc2ef;
  --navy-soft: #7fa9dc;
  --cyan: #3fd0e6;

  --linear: #ef7a68;
  --ours: #c08cf5;
  --gt: #c3cad4;

  --zc: #6bb4f5;
  --cc: #f0b429;

  --link: #6bb4f5;
  --link-hover: #ffb35c;
  --shadow: 0 1px 2px rgba(0, 0, 0, .4);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 16.5px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  font-variant-numeric: tabular-nums;
}

h1, h2, h3, .display, .statnum, .barval {
  font-family: 'Barlow Semi Condensed', 'Lato', Helvetica, sans-serif;
}

a { color: var(--link); text-decoration: none; }
a:hover { color: var(--link-hover); text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
  border-radius: 2px;
}

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }
.wrap-wide { max-width: var(--wide); margin: 0 auto; padding: 0 22px; }

/* ---------- top bar ---------- */

.topbar {
  position: sticky; top: 0; z-index: 40;
  background: var(--bg);
  border-bottom: 1px solid var(--rule);
}
.topbar-in {
  max-width: var(--wide); margin: 0 auto; padding: 9px 22px;
  display: flex; align-items: center; gap: 16px;
}
.topbar a.home { color: var(--text-soft); font-size: 14.5px; }
.topbar a.home:hover { color: var(--link-hover); }
.topbar .crumb { color: var(--text-soft); font-size: 14.5px; }
.topbar .spacer { flex: 1; }
.topbar nav { display: flex; gap: 15px; flex-wrap: wrap; }
.topbar nav a { font-size: 14.5px; color: var(--text-soft); }
.topbar nav a:hover { color: var(--link-hover); text-decoration: none; }

.theme-toggle {
  font: inherit; font-size: 13.5px;
  background: transparent; color: var(--text-soft);
  border: 1px solid var(--rule); border-radius: 999px;
  padding: 3px 12px; cursor: pointer;
}
.theme-toggle:hover { border-color: var(--rule-strong); color: var(--text); }
[data-theme="dark"] .t-dark { display: none; }
.t-light { display: none; }
[data-theme="dark"] .t-light { display: inline; }

/* ---------- hero ---------- */

.hero { padding: 46px 0 6px; }

.venue {
  display: inline-flex; align-items: center; gap: 9px;
  font-size: 14px; letter-spacing: .01em;
  color: var(--navy); font-weight: 700;
}
.venue .tick { width: 26px; height: 3px; background: var(--cyan); display: inline-block; }

h1.title {
  font-size: clamp(44px, 8.4vw, 88px);
  font-weight: 700; letter-spacing: -.022em;
  line-height: .95; margin: 14px 0 6px;
  color: var(--navy);
}
.subtitle {
  font-size: clamp(19px, 2.6vw, 25px);
  line-height: 1.3; font-weight: 400;
  color: var(--text); max-width: 27em; margin: 0 0 22px;
}
.authors { font-size: 16px; margin: 0 0 4px; }
.authors b { font-weight: 700; }
.authors sup { color: var(--navy-soft); font-size: 12px; }
.affil { font-size: 13.5px; color: var(--text-soft); margin: 0 0 22px; max-width: 46em; }
.affil sup { color: var(--navy-soft); }

.links { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 34px; }
.links a, .links button {
  font: inherit; font-size: 14.5px; font-weight: 700;
  display: inline-flex; align-items: center; gap: 7px;
  padding: 7px 15px; border-radius: 999px;
  border: 1px solid var(--rule-strong);
  background: var(--panel); color: var(--text);
  cursor: pointer; text-decoration: none;
}
.links a:hover, .links button:hover {
  border-color: var(--navy); color: var(--navy);
  text-decoration: none;
}
.links a svg, .links button svg { width: 15px; height: 15px; fill: currentColor; }

/* ---------- hero triptych ---------- */

.triptych {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 14px; margin: 0 0 10px;
}
.tri { margin: 0; }
.tri figcaption {
  font-size: 12.5px; font-weight: 700; color: var(--text-soft);
  padding-top: 7px;
}
.tri img {
  width: 100%; aspect-ratio: 1; object-fit: cover; display: block;
  border: 2px solid var(--rule);
}
.tri-gt img { border-color: var(--gt); }
.tri-lin img { border-color: var(--linear); }
.tri-mlp img { border-color: var(--ours); }
.tri-gt figcaption { color: var(--gt); }
.tri-lin figcaption { color: var(--linear); }
.tri-mlp figcaption { color: var(--ours); }

.tri-foot {
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  font-size: 13.5px; color: var(--text-soft);
  border-top: 1px solid var(--rule); padding-top: 10px; margin-bottom: 40px;
}
.dots { display: flex; gap: 5px; }
.dot {
  width: 9px; height: 9px; padding: 0; border-radius: 50%;
  border: 1px solid var(--rule-strong); background: transparent; cursor: pointer;
}
.dot[aria-current="true"] { background: var(--navy); border-color: var(--navy); }

/* ---------- sections ---------- */

section { padding: 40px 0; scroll-margin-top: 58px; }
section + section { border-top: 1px solid var(--rule); }

h2 {
  font-size: clamp(26px, 3.4vw, 36px); font-weight: 700;
  letter-spacing: -.015em; line-height: 1.1;
  margin: 0 0 6px; color: var(--text);
}
h2 .num {
  color: var(--cyan); font-weight: 700;
  margin-right: 10px; font-size: .8em; vertical-align: 2px;
}
h3 { font-size: 19px; margin: 26px 0 6px; font-weight: 700; }
.lede { font-size: 17.5px; color: var(--text-soft); max-width: 34em; margin: 0 0 24px; }
p { max-width: 38em; }
.note { font-size: 14px; color: var(--text-soft); max-width: 42em; }

.pull {
  border-left: 3px solid var(--cyan);
  padding: 2px 0 2px 18px; margin: 26px 0;
  font-size: 19px; line-height: 1.45; max-width: 32em;
}

/* ---------- interactive panel shell ---------- */

.panel {
  background: var(--bg-sunk);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--navy);
  padding: 20px 22px 24px;
  margin: 8px 0 14px;
}
.panel-head {
  display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap;
  margin-bottom: 16px;
}
.panel-head h3 { margin: 0; font-size: 17px; }
.panel-head .hint { font-size: 13.5px; color: var(--text-soft); }

.switch { display: inline-flex; border: 1px solid var(--rule-strong); border-radius: 999px; overflow: hidden; }
.switch button {
  font: inherit; font-size: 13.5px; font-weight: 700;
  padding: 5px 14px; border: 0; background: transparent;
  color: var(--text-soft); cursor: pointer;
}
.switch button + button { border-left: 1px solid var(--rule-strong); }
.switch button[aria-pressed="true"] { background: var(--navy); color: #fff; }
[data-theme="dark"] .switch button[aria-pressed="true"] { color: #15171c; }
.switch button:hover:not([aria-pressed="true"]) { color: var(--text); }

.controls { display: flex; gap: 14px; flex-wrap: wrap; align-items: center; margin-bottom: 16px; }
.ctl-label { font-size: 13px; color: var(--text-soft); font-weight: 700; }

/* ---------- hierarchy explorer ---------- */

.hier { display: grid; grid-template-columns: 1.15fr 1fr; gap: 26px; align-items: start; }
.hier svg { width: 100%; height: auto; display: block; }

.roi { cursor: pointer; }
.roi .roi-fill { fill: var(--rule); stroke: var(--rule-strong); stroke-width: 1.5; transition: fill .18s; }
.roi:hover .roi-fill { fill: var(--rule-strong); }
.roi .roi-text { fill: var(--text); font-size: 12px; font-weight: 700; pointer-events: none; }
.roi.on-early .roi-fill { fill: var(--zc); stroke: var(--zc); }
.roi.on-ventral .roi-fill { fill: var(--cc); stroke: var(--cc); }
.roi.on-early .roi-text, .roi.on-ventral .roi-text { fill: #fff; }
[data-theme="dark"] .roi.on-early .roi-text,
[data-theme="dark"] .roi.on-ventral .roi-text { fill: #15171c; }

.flowline { stroke-width: 2.5; fill: none; opacity: .22; transition: opacity .25s, stroke-width .25s; }
.flowline.live { opacity: 1; stroke-width: 4; }
.axistext { fill: var(--text-soft); font-size: 11.5px; font-family: 'Lato', sans-serif; }
.latentbox { transition: opacity .25s; }
.latentbox.dim { opacity: .28; }

.readout { border-top: 1px solid var(--rule); padding-top: 4px; }
.readout .kicker { font-size: 13px; font-weight: 700; color: var(--text-soft); margin: 14px 0 2px; }
.readout .verdict { font-size: 21px; font-weight: 700; line-height: 1.25; margin: 0 0 10px; font-family: 'Barlow Semi Condensed', sans-serif; }
.readout p { font-size: 14.5px; max-width: none; }

.barrow { margin: 9px 0; }
.barrow .barlabel { font-size: 13px; color: var(--text-soft); display: flex; justify-content: space-between; }
.bartrack { height: 16px; background: var(--rule); position: relative; overflow: hidden; }
.barfill { height: 100%; width: 0; transition: width .7s cubic-bezier(.2,.7,.3,1); }
.barfill.ridge { background: var(--linear); }
.barfill.mlp { background: var(--ours); }
.barval { font-weight: 700; }

.delta {
  display: inline-block; font-weight: 700; font-size: 15px;
  border: 1px solid currentColor; padding: 1px 9px; border-radius: 999px;
  color: var(--ours);
}

/* ---------- pipeline stepper ---------- */

.stepper svg { width: 100%; height: auto; display: block; }
.stage { transition: opacity .3s; }
.stage.dim { opacity: .25; }
.stagebox { fill: var(--panel); stroke: var(--rule-strong); stroke-width: 1.5; }
.stage.active .stagebox { stroke: var(--navy); stroke-width: 2.5; }
.stagelabel { fill: var(--text); font-size: 12.5px; font-weight: 700; font-family: 'Lato', sans-serif; }
.stagesub { fill: var(--text-soft); font-size: 11px; font-family: 'Lato', sans-serif; }

.steptext { min-height: 96px; margin-top: 6px; }
.steptext .stepname { font-size: 19px; font-weight: 700; font-family: 'Barlow Semi Condensed', sans-serif; }
.steptext p { font-size: 15px; margin: 4px 0 0; }

.stepnav { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-top: 12px; }
.btn {
  font: inherit; font-size: 14px; font-weight: 700;
  border: 1px solid var(--rule-strong); background: var(--panel); color: var(--text);
  padding: 5px 14px; border-radius: 999px; cursor: pointer;
}
.btn:hover { border-color: var(--navy); color: var(--navy); }
.btn[disabled] { opacity: .45; cursor: default; }
.btn.primary { background: var(--navy); border-color: var(--navy); color: #fff; }
[data-theme="dark"] .btn.primary { color: #15171c; }

/* ---------- reconstruction explorer ---------- */

.recon { display: grid; grid-template-columns: 1fr 1.25fr; gap: 26px; align-items: start; }
.thumbs { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; }
.thumbs button { padding: 0; border: 2px solid transparent; background: none; cursor: pointer; line-height: 0; }
.thumbs img { width: 100%; aspect-ratio: 1; object-fit: cover; display: block; }
.thumbs button[aria-pressed="true"] { border-color: var(--navy); }
.thumbs button:hover { border-color: var(--cyan); }

.compare { position: relative; user-select: none; touch-action: none; }
.compare .layer { display: block; width: 100%; aspect-ratio: 1; object-fit: cover; }
.compare .over { position: absolute; inset: 0; overflow: hidden; width: 50%; }
.compare .over img { width: 100%; height: 100%; object-fit: cover; display: block; }
.compare .handle {
  position: absolute; top: 0; bottom: 0; width: 3px; background: var(--cyan);
  transform: translateX(-1.5px); cursor: ew-resize;
}
.compare .knob {
  position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  width: 30px; height: 30px; border-radius: 50%; background: var(--cyan);
  display: grid; place-items: center; color: #08232a; font-size: 13px; font-weight: 700;
}
.compare .tag {
  position: absolute; bottom: 8px; font-size: 12px; font-weight: 700;
  padding: 2px 8px; color: #fff; background: rgba(0,0,0,.62);
}
.compare .tag.l { left: 8px; }
.compare .tag.r { right: 8px; }

.recon-side { display: grid; grid-template-columns: 1fr 1.6fr; gap: 14px; align-items: start; }
.seenwrap { margin: 0; }
.seenwrap img { width: 100%; aspect-ratio: 1; object-fit: cover; display: block; border: 2px solid var(--gt); }
.seenwrap .cap { font-size: 12.5px; font-weight: 700; color: var(--gt); padding-top: 6px; }
.coco { font-size: 14px; color: var(--text-soft); margin-top: 10px; }
.coco b { color: var(--text); }

/* ---------- charts ---------- */

.chartbox { position: relative; }
.chartbox svg { width: 100%; height: auto; display: block; overflow: visible; }
.gridline { stroke: var(--rule); stroke-width: 1; }
.axisline { stroke: var(--rule-strong); stroke-width: 1.2; }
.ticktext { fill: var(--text-soft); font-size: 11px; font-family: 'Lato', sans-serif; }
.serieslabel { font-size: 12.5px; font-weight: 700; font-family: 'Lato', sans-serif; }
.errbar { stroke-width: 1.4; }
.pt { cursor: pointer; }

.legend { display: flex; gap: 16px; flex-wrap: wrap; font-size: 13.5px; color: var(--text-soft); margin-top: 10px; }
.legend span { display: inline-flex; align-items: center; gap: 6px; }
.swatch { width: 13px; height: 13px; display: inline-block; border-radius: 2px; }
.legend button {
  font: inherit; font-size: 13.5px; background: none; border: 0; cursor: pointer;
  color: var(--text-soft); display: inline-flex; align-items: center; gap: 6px; padding: 0;
}
.legend button[aria-pressed="false"] { opacity: .38; }

.tip {
  position: absolute; pointer-events: none; opacity: 0;
  background: var(--text); color: var(--bg);
  font-size: 12.5px; padding: 4px 9px; border-radius: 3px;
  transform: translate(-50%, -140%); white-space: nowrap; transition: opacity .12s;
}
.tip.on { opacity: 1; }

canvas.scatter { width: 100%; display: block; }

/* ---------- tables ---------- */

.tablewrap { overflow-x: auto; margin: 12px 0 8px; }
table.data { border-collapse: collapse; width: 100%; font-size: 14.5px; }
table.data th, table.data td { padding: 7px 11px; text-align: right; border-bottom: 1px solid var(--rule); }
table.data th:first-child, table.data td:first-child { text-align: left; }
table.data thead th { color: var(--text-soft); font-weight: 700; font-size: 13px; border-bottom: 1px solid var(--rule-strong); }
table.data td.best { font-weight: 700; color: var(--ours); }
table.data tbody tr:hover { background: var(--bg-sunk); }
table.data .grouphead { color: var(--text-soft); font-size: 13px; font-weight: 700; }

/* ---------- figures ---------- */

figure.fig { margin: 22px 0; }
figure.fig img {
  width: 100%; display: block; border: 1px solid var(--rule);
  background: #fff; cursor: zoom-in;
}
[data-theme="dark"] figure.fig img { filter: invert(0); }
figure.fig figcaption { font-size: 13.5px; color: var(--text-soft); padding-top: 9px; max-width: 44em; }
figure.fig figcaption b { color: var(--text); }

.lightbox {
  position: fixed; inset: 0; z-index: 90; display: none;
  background: rgba(8, 11, 16, .9); padding: 28px; cursor: zoom-out;
  align-items: center; justify-content: center;
}
.lightbox.on { display: flex; }
.lightbox img { max-width: 100%; max-height: 100%; background: #fff; }

/* ---------- takeaways ---------- */

.takeaways { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; margin: 22px 0 6px; }
.takeaway { padding: 0 20px; border-left: 2px solid var(--cyan); }
.takeaway:first-child { padding-left: 0; border-left: 0; }
.takeaway h3 { margin: 0 0 4px; font-size: 17px; }
.takeaway p { font-size: 14.5px; margin: 0; color: var(--text-soft); max-width: none; }
.takeaway .statnum { font-size: 30px; font-weight: 700; color: var(--navy); line-height: 1; display: block; margin-bottom: 6px; }

/* ---------- bibtex ---------- */

pre.bib {
  background: var(--bg-sunk); border: 1px solid var(--rule);
  padding: 16px 18px; overflow-x: auto; font-size: 13px; line-height: 1.5;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}
.copyrow { display: flex; gap: 10px; align-items: center; margin-top: 10px; }
.copied { font-size: 13.5px; color: var(--text-soft); opacity: 0; transition: opacity .2s; }
.copied.on { opacity: 1; }

/* ---------- footer ---------- */

footer {
  border-top: 1px solid var(--rule); padding: 28px 0 60px;
  font-size: 14px; color: var(--text-soft);
}
footer p { max-width: 42em; }

/* ---------- responsive ---------- */

@media (max-width: 860px) {
  .hier, .recon { grid-template-columns: 1fr; }
  .takeaways { grid-template-columns: 1fr; gap: 18px; }
  .takeaway { padding: 0 0 0 16px; border-left: 2px solid var(--cyan); }
  .takeaway:first-child { padding-left: 16px; border-left: 2px solid var(--cyan); }
  .topbar nav { display: none; }
  body { font-size: 16px; }
  .panel { padding: 16px 14px 20px; }
}
@media (max-width: 560px) {
  .thumbs { grid-template-columns: repeat(7, 1fr); }
  .recon-side { grid-template-columns: 1fr; }
  .triptych { gap: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  html { scroll-behavior: auto; }
}