/* ---------- Base ---------- */
:root {
  --bg: #ffffff;
  --fg: #1f2933;
  --muted: #5b6772;
  --accent: #1f6f8b;
  --accent-2: #b13768;
  --rule: #e6e9ec;
  --code-bg: #f6f8fa;
  --max-width: 920px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: "Source Sans 3", "Source Sans Pro", -apple-system, BlinkMacSystemFont,
               "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

main, header, footer { display: block; }

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

code, pre, kbd {
  font-family: "JetBrains Mono", "SF Mono", Menlo, Monaco, Consolas,
               "Liberation Mono", monospace;
}

/* ---------- Layout ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

section { padding: 56px 0; border-bottom: 1px solid var(--rule); }
section:last-of-type { border-bottom: 0; }

h1, h2, h3, h4 {
  font-family: "Source Serif 4", "Source Serif Pro", Georgia, "Times New Roman", serif;
  font-weight: 600;
  color: #14202b;
  line-height: 1.25;
  margin: 0 0 0.5em;
}
h2 {
  font-size: 1.75rem;
  letter-spacing: -0.005em;
  margin-bottom: 1rem;
}
h3 {
  font-size: 1.2rem;
  margin-top: 1.75em;
  margin-bottom: 0.6em;
}

p { margin: 0 0 1em; }

/* ---------- Header / Hero ---------- */
.hero {
  padding: 64px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--rule);
}

.hero .venue {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-2);
  border: 1px solid var(--accent-2);
  border-radius: 999px;
  padding: 3px 12px;
  margin-bottom: 18px;
}

.hero h1 {
  font-size: clamp(1.7rem, 4.2vw, 2.6rem);
  line-height: 1.18;
  margin-bottom: 0.4em;
}

.hero .subtitle {
  color: var(--muted);
  font-size: 1.05rem;
  margin-bottom: 1.5em;
}

.authors {
  font-size: 1.02rem;
  margin: 0.4em 0 0.4em;
  color: #2c3a48;
}
.authors a { color: #2c3a48; }
.authors .author { white-space: nowrap; margin: 0 0.15em; }
.authors sup { font-size: 0.72em; color: var(--accent); margin-left: 1px; }

.affiliations {
  color: var(--muted);
  font-size: 0.92rem;
  margin: 0.6em 0 1.5em;
}
.affiliations sup { color: var(--accent); margin-right: 2px; }
.affiliations span { margin: 0 0.6em; white-space: nowrap; }

/* ---------- Action buttons ---------- */
.actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 22px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 16px;
  background: #1f2933;
  color: #fff !important;
  border-radius: 999px;
  font-size: 0.93rem;
  font-weight: 500;
  border: 1px solid #1f2933;
  transition: background 120ms ease, transform 120ms ease;
}
.btn:hover {
  background: #2c3a48;
  text-decoration: none;
  transform: translateY(-1px);
}
.btn.placeholder {
  background: transparent;
  color: #6b7682 !important;
  border-color: #cdd4dc;
  pointer-events: none;
  opacity: 0.85;
}
.btn .ico {
  display: inline-block;
  width: 16px; height: 16px;
  vertical-align: -3px;
}

/* ---------- Abstract ---------- */
.abstract {
  background: #fafbfc;
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 24px 28px;
  font-size: 1rem;
}
.abstract h2 {
  font-size: 1.25rem;
  margin-top: 0;
  margin-bottom: 0.6em;
}

/* ---------- Highlights ---------- */
.highlights {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin: 18px 0 8px;
}
.highlight {
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 16px 18px;
  background: #fff;
}
.highlight .num {
  font-family: "Source Serif 4", Georgia, serif;
  font-size: 1.7rem;
  font-weight: 600;
  color: var(--accent-2);
  line-height: 1;
}
.highlight .label {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 4px;
}

/* ---------- Figures ---------- */
figure {
  margin: 18px 0 8px;
  text-align: center;
}
figure img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
}
figcaption {
  color: var(--muted);
  font-size: 0.88rem;
  margin-top: 8px;
  line-height: 1.5;
  text-align: left;
}

.fig-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin: 12px 0;
}
.fig-grid-2 figure { margin: 0; }

@media (max-width: 640px) {
  .fig-grid-2 { grid-template-columns: 1fr; }
}

.fig-grid-4 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 12px 0;
}
.fig-grid-4 figure { margin: 0; }

/* ---------- Math block ---------- */
.math-block {
  background: #fafbfc;
  border-left: 3px solid var(--accent);
  padding: 14px 18px;
  margin: 18px 0;
  font-family: "Source Serif 4", Georgia, serif;
  font-size: 1.05rem;
  overflow-x: auto;
}
.math-block .label {
  display: block;
  font-family: inherit;
  color: var(--muted);
  font-size: 0.85rem;
  margin-top: 4px;
}

/* ---------- Algorithm steps ---------- */
.steps {
  counter-reset: step;
  padding-left: 0;
  list-style: none;
}
.steps > li {
  counter-increment: step;
  position: relative;
  padding: 12px 0 12px 48px;
  border-top: 1px solid var(--rule);
}
.steps > li:last-child { border-bottom: 1px solid var(--rule); }
.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 0; top: 14px;
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  font-family: "Source Serif 4", Georgia, serif;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
}
.steps strong { color: #14202b; }

/* ---------- Code block ---------- */
pre.code {
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 14px 18px;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.55;
  white-space: pre;
}
code.inline {
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 1px 6px;
  font-size: 0.88em;
}

/* ---------- Tables ---------- */
.table-scroll {
  overflow-x: auto;
  margin: 16px 0 6px;
  border-radius: 8px;
  border: 1px solid var(--rule);
}

table.compare,
table.results {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 0;
  background: #fff;
}

table.compare th, table.compare td,
table.results th, table.results td {
  border-bottom: 1px solid var(--rule);
  padding: 8px 10px;
  text-align: right;
  white-space: nowrap;
}

/* Left-align only the header's first two columns and the body's label
   cells. nth-child on body rows is unreliable because the rowspan'd
   dataset cell shifts child indices on the second row of each group. */
table.compare thead th:first-child,
table.compare thead th:nth-child(2),
table.results thead th:first-child,
table.results thead th:nth-child(2),
table.compare td.ds,
table.compare td.model,
table.results td.ds {
  text-align: left;
}

table.compare thead th,
table.results thead th {
  border-bottom: 2px solid #c3cad1;
  font-weight: 600;
  background: #f6f8fa;
  position: sticky;
  top: 0;
}

table.compare .best { color: var(--accent-2); font-weight: 600; }

/* dataset label cells (multi-row groups) */
table.compare td.ds,
table.results td.ds {
  font-weight: 600;
  background: #fafbfc;
  vertical-align: middle;
  text-align: left;
  border-right: 1px solid var(--rule);
}

/* keep every cell vertically centered so rowspan cells line up */
table.compare th, table.compare td,
table.results th, table.results td {
  vertical-align: middle;
}

/* green / red cells for results table */
table.results td.good {
  background-color: #d4ecd4;
  color: #14431a;
}
table.results td.bad {
  background-color: #fbcdcd;
  color: #7a1414;
  font-weight: 500;
}

/* inline cell-color key chips for prose */
.cell-key {
  display: inline-block;
  padding: 0 8px;
  border-radius: 4px;
  font-weight: 500;
}
.cell-key.good { background: #d4ecd4; color: #14431a; }
.cell-key.bad  { background: #fbcdcd; color: #7a1414; }

/* caption under tables */
p.caption {
  color: var(--muted);
  font-size: 0.88rem;
  margin-top: 6px;
}

/* ---------- Examples list ---------- */
ul.examples {
  list-style: none;
  padding: 0;
  margin: 12px 0 0;
}
ul.examples li {
  padding: 12px 16px 12px 18px;
  border-left: 3px solid var(--accent);
  background: #fafbfc;
  margin-bottom: 10px;
  border-radius: 0 8px 8px 0;
}
ul.examples li strong { color: #14202b; }


/* ---------- Diagram-style figures (sized to actual content) ---------- */
figure.figure-causal {
  max-width: 360px;
  margin-left: auto;
  margin-right: auto;
}
figure.figure-causal img { max-width: 100%; }

figure.figure-flow {
  max-width: 460px;
  margin-left: auto;
  margin-right: auto;
}
figure.figure-flow img { max-width: 100%; }

/* ---------- Pip package callout ---------- */
.pkg-callout {
  background: linear-gradient(180deg, #fdf7f0 0%, #fdf3ea 100%);
  border: 1px solid #f0d7be;
  border-radius: 12px;
  padding: 24px 26px;
  margin-top: 8px;
}
.pkg-callout h3 { margin-top: 0; }
.pkg-callout .small {
  color: var(--muted);
  font-size: 0.92rem;
}

/* ---------- BibTeX ---------- */
.bibtex {
  background: var(--code-bg);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 16px 18px;
  font-size: 0.85rem;
  line-height: 1.5;
  white-space: pre-wrap;
  word-break: break-word;
}

/* ---------- Footer ---------- */
footer {
  padding: 28px 0 48px;
  color: var(--muted);
  font-size: 0.88rem;
  text-align: center;
}
footer a { color: var(--muted); }