:root {
  --text: #1a1a1a;
  --muted: #555;
  --faint: #888;
  --accent: #0b5fa5;
  --bg: #ffffff;
  --bg-alt: #f6f8fa;
  --border: #e1e4e8;
  --radius: 10px;
}

* { box-sizing: border-box; }

img, video { max-width: 100%; height: auto; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 17px;
}

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- Hero ---------- */

header {
  padding: 56px 0 8px;
  text-align: center;
}

h1.title {
  font-size: 1.9rem;
  line-height: 1.3;
  margin: 0 auto 20px;
  max-width: 1000px;
  font-weight: 700;
}

.authors {
  font-size: 1.05rem;
  margin: 0 auto 6px;
  max-width: 800px;
}

.authors a {
  color: var(--accent);
  text-decoration: none;
}

.authors a:hover { text-decoration: underline; }

.authors sup { font-size: 0.72em; }

.affiliations {
  color: var(--muted);
  font-size: 0.95rem;
  margin: 0 0 4px;
}

.equal-note {
  color: var(--faint);
  font-size: 0.85rem;
  margin: 0 0 6px;
}

.venue-note {
  color: var(--accent);
  font-size: 1rem;
  font-weight: 600;
  margin: 0 0 24px;
}

/* ---------- Buttons ---------- */

.buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-bottom: 36px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 18px;
  border-radius: 999px;
  background: #222;
  color: #fff;
  text-decoration: none;
  font-size: 0.95rem;
  border: none;
  transition: background 0.15s ease;
}

.btn:hover { background: var(--accent); }

.btn.disabled {
  background: #e8e8e8;
  color: var(--faint);
  cursor: default;
  pointer-events: none;
}

/* ---------- Video / teaser ---------- */

.hero-media {
  position: relative;
  margin: 0 0 12px;
}

.hero-media video,
.hero-media img {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.coming-soon-badge {
  position: absolute;
  top: 14px;
  right: 14px;
  background: rgba(0, 0, 0, 0.65);
  color: #fff;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 0.82rem;
  letter-spacing: 0.02em;
}

.caption {
  color: var(--muted);
  font-size: 0.9rem;
  text-align: center;
  margin: 8px auto 0;
  max-width: 800px;
}

/* ---------- Sections ---------- */

section { padding: 28px 0; }

section + section { border-top: 1px solid var(--border); }

h2 {
  font-size: 1.65rem;
  text-align: center;
  margin: 0 0 18px;
}

h3 {
  font-size: 1.12rem;
  margin: 24px 0 8px;
}

p { margin: 0 0 14px; }

.abstract p {
  text-align: justify;
}

/* ---------- Figures ---------- */

figure {
  margin: 20px 0;
}

figure img,
figure video {
  width: 100%;
  display: block;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: #fff;
}

figure figcaption {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 8px;
  text-align: center;
}

.fig-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  align-items: start;
}

/* Embedded interactive Bubble* demo (docs/bubble-star-demo/) */
.demo-embed iframe {
  display: block;
  width: 100%;
  height: 800px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
}

@media (max-width: 640px) {
  .demo-embed iframe { height: 440px; }
}

/* 2x2 simulation video grid: forest column left, industrial column right. */
.video-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px 18px;
  align-items: start;
  margin: 20px 0;
}

.video-grid .grid-label {
  text-align: center;
  font-weight: 600;
  color: var(--muted);
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

.video-grid figure { margin: 0 0 10px; }

/* Side-by-side media of different aspect ratios rendered at equal height;
   flex values are set to each pane's media aspect ratio. */
.split-view {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  margin: 20px 0;
}

.split-view figure {
  margin: 0;
  min-width: 0;
}

.split-view .pane-video { flex: 1.778 1 0; }
.split-view .pane-image { flex: 1.494 1 0; }

@media (max-width: 640px) {
  .fig-row { grid-template-columns: 1fr; }
  .split-view { flex-direction: column; }
  /* Single column breaks the forest/industrial pairing, so drop the column
     labels and let the captions name the environment. */
  .video-grid { grid-template-columns: 1fr; }
  .video-grid .grid-label { display: none; }
  h1.title { font-size: 1.5rem; }
}

/* ---------- Stats ---------- */

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin: 22px 0;
}

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

.stat {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
}

.stat .num {
  font-size: 1.7rem;
  font-weight: 700;
  color: var(--accent);
}

.stat .desc {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 4px;
}

/* ---------- Code / BibTeX ---------- */

pre {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
}

code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

p code, li code {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 0.85em;
}

/* ---------- Links section ---------- */

.links-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

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

.link-card {
  display: block;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s ease;
}

.link-card:hover { border-color: var(--accent); }

.link-card .name {
  font-weight: 600;
  color: var(--accent);
}

.link-card .detail {
  color: var(--muted);
  font-size: 0.88rem;
}

/* ---------- Footer ---------- */

footer {
  border-top: 1px solid var(--border);
  padding: 24px 0 40px;
  color: var(--muted);
  font-size: 0.9rem;
  text-align: center;
}

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