/* TUCO project page, v2.
   One content column (960 px) for every element; plain section titles; minimal chrome.
   Type: Source Serif 4 (title, section headings), Inter (text, UI), JetBrains Mono (BibTeX).
   Accent: #6a3d9a, the purple that marks TUCO in the paper's figures. */

:root {
  --bg: #ffffff;
  --surface: #f7f6fa;
  --ink: #1c1a22;
  --ink-2: #3a3743;
  --muted: #6c6877;
  --rule: #e4e1ea;
  --rule-soft: #efedf3;

  --accent: #6a3d9a;
  --accent-ink: #55307f;
  --accent-tint: #f3eefa;

  --tbd-bg: #fff3cf;
  --tbd-ink: #7a4a00;
  --tbd-line: #d9a12a;

  --serif: "Source Serif 4", "Source Serif Pro", Georgia, "Times New Roman", serif;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --content: 960px;
  --gutter: 16px;
}

/* ---------- base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink-2);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-wrap: break-word;
}
img, video { max-width: 100%; }
img { height: auto; }
p { margin: 0 0 1em; }
a { color: var(--accent-ink); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--accent); }
strong { color: var(--ink); font-weight: 600; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
sup { font-size: 0.66em; line-height: 0; position: relative; top: -0.15em; }

.vh {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.skip { position: absolute; left: 12px; top: -48px; z-index: 10; background: var(--ink); color: #fff;
  padding: 8px 14px; border-radius: 8px; font-size: 14px; text-decoration: none; }
.skip:focus { top: 12px; color: #fff; }

/* the single content column */
.page {
  width: min(var(--content), calc(100% - 2 * var(--gutter)));
  margin: 0 auto;
  padding-bottom: 88px;
}

/* placeholder marker: must never look like final content */
.tbd {
  font-family: var(--mono);
  font-size: 0.82em;
  font-weight: 500;
  color: var(--tbd-ink);
  background: var(--tbd-bg);
  border: 1px dashed var(--tbd-line);
  border-radius: 4px;
  padding: 0.05em 0.4em;
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
}

/* ---------- hero ---------- */
.hero { padding-top: clamp(44px, 8vw, 84px); text-align: center; }
.title { margin: 0 0 22px; font-family: var(--serif); color: var(--ink); font-weight: 600; }
.title-acr {
  display: block;
  font-weight: 700;
  font-size: clamp(52px, 9vw, 76px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--accent);
  margin-bottom: 12px;
}
.title-sub {
  display: block;
  max-width: 820px;
  margin-inline: auto;
  font-size: clamp(22px, 3vw, 31px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  text-wrap: balance;
}
.authors {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 2px 20px;
  max-width: 820px;
  margin: 0 auto 6px;
  font-size: 17.5px;
  color: var(--ink);
}
.author { white-space: nowrap; }
.author .tbd { white-space: normal; }
.authors sup { color: var(--accent); font-weight: 600; margin-left: 1px; }
.authors sup .tbd { font-size: 1em; }
.affiliations {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 0 20px;
  margin: 0 0 2px;
  font-size: 15px;
  color: var(--muted);
}
.affiliations sup { color: var(--accent); font-weight: 600; margin-right: 2px; }
.equal { margin: 0 0 22px; font-size: 13.5px; color: var(--muted); }

.links { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.pill {
  display: inline-flex; align-items: center; gap: 7px;
  min-height: 40px;
  padding: 8px 17px 8px 14px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.2;
  text-decoration: none;
  transition: background-color .15s ease;
}
.pill svg { width: 17px; height: 17px; flex: none; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.pill small { font-size: 12px; font-weight: 500; opacity: 0.8; margin-left: 3px; }
a.pill:hover { background: var(--accent); color: #fff; }
.pill.is-disabled { opacity: 0.4; cursor: not-allowed; }

/* ---------- teaser ---------- */
.teaser { margin-top: 40px; }
.teaser video {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  background: #fff;
  border: 1px solid var(--rule);
  border-radius: 8px;
}

/* ---------- sections ---------- */
.section { padding-top: clamp(48px, 6vw, 72px); scroll-margin-top: 8px; }
h2 {
  margin: 0 0 22px;
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(26px, 3vw, 30px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  text-align: center;
  color: var(--ink);
}
.justify { text-align: justify; hyphens: auto; -webkit-hyphens: auto; }

.points { margin: 0 0 1em; padding-left: 1.15em; }
.points li { margin-bottom: 0.55em; padding-left: 0.2em; }
.points li::marker { color: var(--muted); }
.points li:last-child { margin-bottom: 0; }

/* figures: always the full content width */
.fig { margin: 0 0 26px; }
.fig img { display: block; width: 100%; }
.zoom { display: block; cursor: zoom-in; }
#simulation .fig { margin-bottom: 34px; }
#simulation .fig:last-child { margin-bottom: 0; }

.caption { margin: 12px 0 0; text-align: center; font-size: 14px; line-height: 1.5; color: var(--muted); }

/* ---------- rollout grid ---------- */
.rollouts { display: grid; gap: 26px; margin-top: 40px; }
.row-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 10px; }
.row-label { margin: 0; font-family: var(--sans); font-size: 15.5px; font-weight: 600; line-height: 1.3; color: var(--ink); }
.row-play {
  display: inline-flex; align-items: center; gap: 6px;
  min-height: 32px;
  padding: 5px 13px 5px 10px;
  border: 1px solid var(--rule);
  border-radius: 999px;
  background: #fff;
  color: var(--ink-2);
  font: 500 13px/1 var(--sans);
  cursor: pointer;
  white-space: nowrap;
}
.row-play[hidden] { display: none; }
.row-play:hover { border-color: var(--accent); color: var(--accent-ink); }
.row-play svg { width: 13px; height: 13px; fill: currentColor; flex: none; }
.row-play .i-pause, .row-play[aria-pressed="true"] .i-play { display: none; }
.row-play[aria-pressed="true"] .i-pause { display: block; }
.row-play[aria-pressed="true"] { border-color: var(--accent); color: var(--accent-ink); }
.row-clips { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.clip { margin: 0; min-width: 0; }
.clip-head { margin-bottom: 6px; text-align: center; font-size: 13.5px; line-height: 1.35; }
.clip-name { color: var(--ink-2); font-weight: 500; }
.clip-rate { color: var(--muted); white-space: nowrap; font-variant-numeric: lining-nums tabular-nums; }
.clip.is-ours .clip-name { color: var(--accent-ink); font-weight: 600; }
.clip.is-ours .clip-rate { color: var(--accent-ink); }
.clip-media { position: relative; border-radius: 6px; overflow: hidden; background: #16141c; }
.clip-media video { display: block; width: 100%; height: auto; }
.rollouts.is-interactive .clip-media { cursor: pointer; }
.rollouts.is-interactive .clip-media::after {
  content: "";
  position: absolute; left: 50%; top: 50%;
  width: 40px; height: 40px; margin: -20px 0 0 -20px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.9) 55% 50% / 16px no-repeat url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6 3.5v17l14-8.5z' fill='%231c1a22'/%3E%3C/svg%3E");
  pointer-events: none;
  transition: opacity .15s ease;
}
.rollouts.is-interactive .clip.is-playing .clip-media::after { opacity: 0; }

/* ---------- real-world: lead claim + chart ---------- */
.setup { margin: 0 0 32px; }
.intro { margin-bottom: 1.4em; }
#method .intro { margin-bottom: 28px; }
.steps { margin-top: 4px; }
.steps li { margin-bottom: 0.8em; }
#simulation p:not(.intro) { margin-bottom: 14px; }
.chart { margin: 0; }
.chart-title { margin: 0 0 8px; font-family: var(--sans); font-size: 16px; font-weight: 600; color: var(--ink); }
.chart-legend {
  display: flex; flex-wrap: wrap;
  gap: 4px 18px;
  margin: 0 0 6px; padding: 0;
  list-style: none;
  font-size: 13.5px; line-height: 1.5;
  color: var(--ink-2);
}
.chart-legend li { display: inline-flex; align-items: center; gap: 7px; white-space: nowrap; }
.chart-legend .key { width: 24px; height: 12px; flex: none; overflow: visible; }
.chart-legend .key-ours { color: var(--ink); font-weight: 600; }
.chart-plot { position: relative; touch-action: pan-y; }
.chart-plot svg { display: block; width: 100%; height: auto; overflow: visible; }
.chart-plot:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
.chart-tip {
  position: absolute; top: 0; left: 0; z-index: 2;
  min-width: 190px;
  padding: 8px 10px;
  background: #fff;
  border: 1px solid var(--rule);
  border-radius: 6px;
  box-shadow: 0 4px 14px rgba(28, 20, 50, 0.12);
  font-size: 12.5px; line-height: 1.5;
  color: var(--ink-2);
  pointer-events: none;
}
.chart-tip[hidden] { display: none; }
.chart-tip .tip-head { font-weight: 600; color: var(--ink); margin-bottom: 2px; }
.chart-tip .tip-row { display: flex; align-items: center; gap: 7px; }
.chart-tip .tip-row svg { width: 16px; height: 8px; flex: none; }
.chart-tip .tip-name { flex: 1; }
.chart-tip .tip-val { font-variant-numeric: tabular-nums; color: var(--ink); }
.chart-tip .tip-ours { font-weight: 600; color: var(--ink); }
.chart-note { margin: 6px 0 0; font-size: 13px; line-height: 1.5; color: var(--muted); }

/* "Show values": the chart's data as a compact table */
.chart-values { margin-top: 10px; }
.chart-values > summary {
  display: inline-flex; align-items: center; gap: 7px;
  list-style: none;
  cursor: pointer;
  font-size: 13.5px; font-weight: 500;
  color: var(--ink-2);
}
.chart-values > summary::-webkit-details-marker { display: none; }
.chart-values > summary::before {
  content: "";
  width: 6px; height: 6px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(-45deg);
  transition: transform .15s ease;
}
.chart-values[open] > summary::before { transform: rotate(45deg); }
.chart-values > summary:hover { color: var(--accent-ink); }
.values-scroll { margin-top: 10px; overflow-x: auto; -webkit-overflow-scrolling: touch; }
table.values { width: 100%; border-collapse: collapse; font-size: 14px; line-height: 1.35; font-variant-numeric: lining-nums tabular-nums; }
table.values th, table.values td { padding: 7px 10px; border-bottom: 1px solid var(--rule-soft); text-align: left; }
table.values thead th { font-size: 13px; font-weight: 600; color: var(--muted); border-bottom: 1px solid var(--ink); }
table.values .num { text-align: right; white-space: nowrap; width: 14%; }
table.values tbody th { font-weight: 400; color: var(--ink); }
table.values td { color: var(--ink-2); }
table.values tr.ours > * { font-weight: 700; color: var(--ink); background: var(--accent-tint); }

.findings { margin-top: 30px; }

/* ---------- BibTeX ---------- */
.bib { position: relative; }
.bib pre {
  margin: 0;
  padding: 18px 20px;
  background: var(--surface);
  border: 1px solid var(--rule-soft);
  border-radius: 8px;
  white-space: pre-wrap;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.65;
  color: var(--ink);
}
.bib pre .tbd { font-size: 1em; }
.copy {
  position: absolute; top: 10px; right: 10px;
  padding: 5px 11px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background: #fff;
  color: var(--muted);
  font: 500 12.5px/1.2 var(--sans);
  cursor: pointer;
}
.copy:hover { color: var(--accent-ink); border-color: var(--accent); }

/* ---------- lightbox ---------- */
dialog.lightbox { padding: 0; border: 0; background: transparent; max-width: 96vw; max-height: 96vh; overflow: visible; }
dialog.lightbox::backdrop { background: rgba(14, 12, 22, 0.86); }
.lightbox-bar { display: flex; justify-content: flex-end; align-items: center; gap: 14px; height: 44px; }
.lightbox-full { color: #fff; font-size: 14px; }
.lightbox-full:hover { color: #e4dbf3; }
.lightbox-close {
  width: 36px; height: 36px;
  border: 0; border-radius: 50%;
  background: rgba(255, 255, 255, 0.14);
  color: #fff; font-size: 24px; line-height: 1;
  cursor: pointer;
}
.lightbox-close:hover { background: rgba(255, 255, 255, 0.26); }
dialog.lightbox img {
  display: block;
  margin: 0 auto;
  width: auto; height: auto;
  max-width: 96vw;
  max-height: calc(96vh - 52px);
  background: #fff;
  border-radius: 6px;
  cursor: zoom-out;
}

/* ---------- phones ---------- */
@media (max-width: 720px) {
  body { font-size: 16px; line-height: 1.68; }
  .justify { text-align: left; }
  .authors { font-size: 16.5px; gap: 2px 14px; }
  .affiliations { font-size: 14.5px; gap: 0 14px; }
  .pill { padding: 7px 15px 7px 12px; font-size: 14.5px; }
  .teaser { margin-top: 30px; }
  .row-clips { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px 10px; }
  .clip-head { min-height: 2.7em; }
  .chart-legend { font-size: 12.5px; gap: 2px 14px; }
  .setup { margin-bottom: 26px; }
  table.values { font-size: 13px; }
  table.values th, table.values td { padding: 7px 5px; }
  table.values .num { width: auto; }
  .bib pre { font-size: 12px; padding: 14px; }
}