:root {
  --ink: #1f252b;
  --muted: #66717d;
  --line: #dfe5ea;
  --soft: #f6f8fa;
  --paper: #ffffff;

  --blue: #1467ad;
  --orange: #df5a2a;
  --green: #08775f;

  --shadow: 0 12px 32px rgba(24, 35, 47, 0.08);
  --radius: 16px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont,
    "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

.shell {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.shell.wide {
  width: min(1380px, calc(100% - 36px));
}

.text-width {
  max-width: 850px;
}

.hero {
  padding: 78px 0 54px;
  background:
    radial-gradient(circle at 12% 10%, rgba(20, 103, 173, 0.11), transparent 28%),
    radial-gradient(circle at 85% 22%, rgba(223, 90, 42, 0.10), transparent 28%),
    #fff;
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  text-align: center;
}

.venue {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(3.4rem, 8vw, 6.1rem);
  line-height: 0.95;
  letter-spacing: -0.055em;
}

h2 {
  max-width: 940px;
  margin: 22px auto 16px;
  font-size: clamp(1.45rem, 3vw, 2.35rem);
  line-height: 1.2;
  letter-spacing: -0.025em;
  font-weight: 650;
}

h2 span {
  white-space: normal;
}

.authors {
  margin: 24px 0 2px;
  font-size: 1.08rem;
  font-weight: 650;
}

.affiliation {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

.resource-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 9px 17px;
  border: 1px solid #cfd6dc;
  border-radius: 999px;
  background: #fff;
  text-decoration: none;
  font-size: 0.91rem;
  font-weight: 700;
  transition:
    transform 120ms ease,
    border-color 120ms ease,
    background 120ms ease;
}

.button:hover {
  transform: translateY(-1px);
  border-color: #9da8b2;
  background: #fafbfc;
}

.button.active {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}

.button.disabled {
  color: #929ba3;
  background: #f3f5f6;
  pointer-events: none;
}

.section {
  padding: 66px 0;
}

.section.soft {
  background: var(--soft);
  border-top: 1px solid #eef1f3;
  border-bottom: 1px solid #eef1f3;
}

h3 {
  margin: 0 0 28px;
  text-align: center;
  font-size: clamp(1.7rem, 3vw, 2.2rem);
  line-height: 1.15;
  letter-spacing: -0.025em;
}

h4 {
  margin: 0 0 8px;
  font-size: 1.12rem;
  line-height: 1.3;
}

p {
  margin: 0 0 1.15em;
}

.teaser-card {
  margin: 0;
}

.teaser {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

figcaption {
  max-width: 940px;
  margin: 18px auto 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.55;
}

.grid {
  display: grid;
  gap: 18px;
}

.grid.three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid.two {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.card {
  position: relative;
  padding: 27px 26px 23px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.card p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.62;
}

.accent {
  position: absolute;
  inset: 0 auto 0 0;
  width: 5px;
}

.accent.blue {
  background: var(--blue);
}

.accent.orange {
  background: var(--orange);
}

.accent.green {
  background: var(--green);
}

.section-intro {
  max-width: 820px;
  margin: -10px auto 30px;
  text-align: center;
  color: var(--muted);
}

.video-placeholder {
  min-height: 180px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 25px;
  border: 1px dashed #b9c2ca;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.62);
  text-align: center;
}

.video-placeholder span {
  font-weight: 750;
}

.video-placeholder small {
  color: var(--muted);
}

.resource-list {
  border-top: 1px solid var(--line);
}

.resource-list > div {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 18px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.resource-list span {
  color: var(--muted);
}

.dark-section {
  background: #20262c;
  color: #fff;
}

.dark-section h3 {
  color: #fff;
}

pre {
  overflow-x: auto;
  margin: 0;
  padding: 22px 24px;
  border: 1px solid #46515b;
  border-radius: 12px;
  background: #15191d;
  color: #edf2f5;
  font-size: 0.84rem;
  line-height: 1.55;
}

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

footer {
  padding: 28px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  text-align: center;
  font-size: 0.86rem;
}

footer p {
  margin: 0;
}

@media (max-width: 820px) {
  body {
    font-size: 16px;
  }

  .hero {
    padding-top: 54px;
  }

  .grid.three,
  .grid.two {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 52px 0;
  }

  .resource-list > div {
    grid-template-columns: 1fr;
    gap: 4px;
  }
}

@media (max-width: 520px) {
  .shell,
  .shell.wide {
    width: min(100% - 24px, 1120px);
  }

  .resource-links {
    gap: 8px;
  }

  .button {
    padding-inline: 13px;
  }

  .teaser {
    border-radius: 10px;
  }
}


/* Five-method comparison videos: wide originals with responsive playback */
.video-gallery {
  display: grid;
  gap: 28px;
  max-width: 1000px;
  margin: 0 auto;
}
.video-card {
  min-width: 0;
  padding: 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.video-card-header,
.video-card-footer {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: baseline;
  flex-wrap: wrap;
}
.video-card-header { padding: 0 4px 10px; }
.video-card-header h4 { margin: 0; }
.video-card-header span,
.video-card-footer { color: var(--muted); font-size: 0.87rem; }
.video-card-footer { padding: 12px 4px 0; }
.video-card-footer a { color: var(--blue); font-weight: 600; }
.comparison-video {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 3;
  background: #121820;
  border-radius: 8px;
}
@media (max-width: 520px) {
  .video-card { padding: 8px; }
  .video-card-header { padding: 4px 5px 9px; }
  .video-card-footer { padding: 10px 5px 4px; }
}


/* In-page conference paper PDF viewer */
.paper-display {
  max-width: 1000px;
  margin: 0 auto;
}
.paper-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 18px;
}
.paper-actions[hidden],
.paper-frame[hidden],
.paper-status[hidden] {
  display: none;
}
.paper-status {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  text-align: center;
  color: var(--muted);
}
.paper-frame {
  display: block;
  width: 100%;
  height: min(78vh, 900px);
  min-height: 540px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}
@media (max-width: 520px) {
  .paper-frame {
    min-height: 420px;
    height: 65vh;
  }
}