:root {
  --primary: #1a1a2e;
  --accent: #4361ee;
  --accent-light: #eef1ff;
  --bg: #ffffff;
  --text: #2d2d2d;
  --text-light: #666;
  --light-bg: #f7f8fc;
  --border: #e4e7ed;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-hover: 0 4px 20px rgba(0,0,0,0.12);
  --radius: 10px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: 'Noto Sans', -apple-system, 'Segoe UI', Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 28px;
}

/* ─── Hero ─── */
.hero {
  text-align: center;
  padding: 70px 0 40px;
  background: linear-gradient(180deg, #e8ecfc 0%, #f2f4fd 100%);
  border-bottom: 1px solid var(--border);
}

.hero h1 {
  font-size: 2.4em;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.25;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.venue {
  display: inline-block;
  font-size: 0.95em;
  color: var(--accent);
  font-weight: 700;
  background: var(--accent-light);
  padding: 4px 18px;
  border-radius: 20px;
  margin-bottom: 20px;
  letter-spacing: 0.5px;
}

.authors {
  font-size: 1.05em;
  color: #444;
  margin-bottom: 6px;
  line-height: 1.6;
}

.affiliations {
  font-size: 0.88em;
  color: var(--text-light);
  margin-bottom: 28px;
}

.links {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

.links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 24px;
  background: var(--accent);
  color: white;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9em;
  transition: all 0.2s;
  box-shadow: 0 2px 8px rgba(67,97,238,0.3);
}

.links a:hover {
  background: #3651d4;
  box-shadow: 0 4px 14px rgba(67,97,238,0.4);
  transform: translateY(-1px);
}

/* ─── Sections ─── */
section {
  padding: 50px 0;
}

.section-divider {
  border: none;
  height: 1px;
  background: var(--border);
  margin: 0;
}

section h2 {
  font-size: 1.7em;
  color: var(--primary);
  margin-bottom: 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

section h2 .section-icon {
  color: var(--accent);
  margin-right: 8px;
}

section > p, section > .section-desc {
  margin-bottom: 20px;
  color: var(--text);
  font-size: 1.0em;
  max-width: 850px;
}

.abstract-text {
  text-align: justify;
  font-size: 1.0em;
  line-height: 1.8;
  background: var(--light-bg);
  padding: 28px 32px;
  border-radius: var(--radius);
  border-left: 4px solid var(--accent);
}

.abstract-text p {
  margin-bottom: 12px;
}

.abstract-text p:last-child {
  margin-bottom: 0;
}

/* ─── Figures ─── */
.figure {
  margin: 28px 0;
  text-align: center;
}

.figure img {
  max-width: 90%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

#teaser .figure img {
  max-width: 85%;
}

.figure .caption {
  font-size: 0.82em;
  color: var(--text-light);
  margin-top: 10px;
  font-style: italic;
  max-width: 750px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.5;
}

/* ─── Demo Gallery ─── */
.demo-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin: 28px 0;
}

.demo-card {
  background: var(--bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: box-shadow 0.2s, transform 0.2s;
}

.demo-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.demo-card .demo-media {
  position: relative;
}

.demo-card .ref-img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
  display: block;
  cursor: pointer;
}

.demo-card video {
  width: 100%;
  display: block;
  cursor: pointer;
}

.demo-card .demo-label {
  position: absolute;
  top: 8px;
  left: 8px;
  background: rgba(0,0,0,0.6);
  color: white;
  font-size: 0.7em;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: 4px;
  pointer-events: none;
}

.demo-card .demo-info {
  padding: 12px 16px;
}

.demo-card .demo-caption {
  font-size: 0.85em;
  color: var(--text-light);
  line-height: 1.4;
}

/* ─── Comparison Section ─── */
.carousel-container {
  position: relative;
  background: var(--light-bg);
  border-radius: var(--radius);
  padding: 24px 8px;
  margin: 20px -28px;
  overflow: visible;
}

.carousel-inner {
  position: relative;
  min-height: 200px;
  max-width: 100%;
  margin: 0 auto;
}

.carousel-slide {
  display: none;
  animation: fadeIn 0.45s ease;
}

.carousel-slide.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateX(12px); }
  to   { opacity: 1; transform: translateX(0); }
}

.carousel-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 2;
  background: white;
  border: 1px solid var(--border);
  color: var(--text);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  font-size: 1.1em;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: all 0.2s;
}

.carousel-arrow:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  box-shadow: 0 4px 12px rgba(67,97,238,0.3);
}

.carousel-prev { left: -20px; }
.carousel-next { right: -20px; }

.carousel-dots {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 20px;
}

.carousel-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--border);
  cursor: pointer;
  transition: all 0.2s;
}

.carousel-dot.active {
  background: var(--accent);
  transform: scale(1.2);
}

.carousel-dot:hover {
  background: var(--accent);
  opacity: 0.7;
}

.comp-prompt {
  font-size: 0.95em;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 16px;
  text-align: center;
}

/* Grid: square cols = 9fr, video cols = 16fr → equal heights (no JS needed) */
.comparison-grid {
  display: grid;
  grid-template-columns: 9fr 9fr 16fr 16fr 16fr 16fr 16fr;
  gap: 8px;
  align-items: end;
}

.comparison-grid .comp-label {
  font-size: 0.72em;
  font-weight: 600;
  color: var(--text-light);
  text-align: center;
  margin-bottom: 4px;
}

.comparison-grid .comp-label.ours-label {
  color: var(--accent);
  font-weight: 700;
}

.comparison-grid .comp-cell {
  text-align: center;
  min-width: 0;
}

.comparison-grid .comp-cell img,
.comparison-grid .comp-cell video {
  width: 100%;
  object-fit: cover;
  border-radius: 6px;
  border: 2px solid var(--border);
  cursor: pointer;
  display: block;
}

.comparison-grid .comp-cell:nth-child(1) img {
  aspect-ratio: 1/1;
}

.comparison-grid .comp-cell:nth-child(2) video {
  aspect-ratio: 1/1;
}

.comparison-grid .comp-cell:nth-child(n+3) video {
  aspect-ratio: 16/9;
}

.comparison-grid .comp-cell.ours-cell video {
  border: 2px solid var(--accent);
}

/* ─── Stats ─── */
.stats-bar {
  display: flex;
  justify-content: center;
  gap: 0;
  margin: 32px 0;
  background: var(--light-bg);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.stat-item {
  flex: 1;
  text-align: center;
  padding: 24px 16px;
  border-right: 1px solid var(--border);
}

.stat-item:last-child {
  border-right: none;
}

.stat-item .stat-num {
  font-size: 2.4em;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.2;
}

.stat-item .stat-label {
  font-size: 0.85em;
  color: var(--text-light);
  margin-top: 4px;
}

/* ─── Benchmark Table ─── */
.table-wrapper {
  overflow-x: auto;
  margin: 24px 0;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.benchmark-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88em;
}

.benchmark-table th {
  background: var(--primary);
  color: white;
  padding: 12px 14px;
  text-align: center;
  font-weight: 600;
  font-size: 0.9em;
}

.benchmark-table th:first-child {
  text-align: left;
  padding-left: 20px;
}

.benchmark-table td {
  padding: 10px 14px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.benchmark-table td:first-child {
  text-align: left;
  padding-left: 20px;
  font-weight: 500;
}

.benchmark-table tr:nth-child(even) {
  background: var(--light-bg);
}

.benchmark-table .best {
  font-weight: 700;
  color: var(--accent);
}

.benchmark-table .second {
  text-decoration: underline;
}

.benchmark-table tr.ours td {
  background: var(--accent-light);
  font-weight: 600;
}

/* ─── BibTeX ─── */
.bibtex-wrapper {
  position: relative;
}

.bibtex {
  background: var(--primary);
  color: #c8d6e5;
  border-radius: var(--radius);
  padding: 20px 24px;
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 0.82em;
  overflow-x: auto;
  white-space: pre;
  line-height: 1.6;
}

/* ─── Lightbox ─── */
.lightbox-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.85);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  cursor: pointer;
}

.lightbox-overlay.active {
  display: flex;
}

.lightbox-overlay video,
.lightbox-overlay img {
  max-width: 85%;
  max-height: 85%;
  border-radius: 12px;
  box-shadow: 0 8px 40px rgba(0,0,0,0.5);
}

.lightbox-close {
  position: absolute;
  top: 24px;
  right: 32px;
  color: white;
  font-size: 2em;
  cursor: pointer;
  font-weight: 300;
  line-height: 1;
  opacity: 0.8;
  transition: opacity 0.2s;
}

.lightbox-close:hover {
  opacity: 1;
}

/* ─── Footer ─── */
footer {
  text-align: center;
  padding: 32px 0;
  color: #999;
  font-size: 0.82em;
  border-top: 1px solid var(--border);
  margin-top: 20px;
}

/* ─── Responsive ─── */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.6em; }
  .demo-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .comparison-grid {
    grid-template-columns: repeat(7, 1fr);
    gap: 4px;
  }
  .carousel-container { padding: 24px 44px; }
  .carousel-arrow { width: 30px; height: 30px; font-size: 0.9em; }
  .carousel-prev { left: 4px; }
  .carousel-next { right: 4px; }
  .stats-bar { flex-direction: column; }
  .stat-item { border-right: none; border-bottom: 1px solid var(--border); }
  .stat-item:last-child { border-bottom: none; }
}