:root {
  --bg: #f4f7fb;
  --card: #ffffff;
  --text: #172033;
  --muted: #647187;
  --primary: #1d5fd1;
  --primary-dark: #11356d;
  --primary-soft: #e9f1ff;
  --border: #dde6f2;
  --accent: #f7fbff;
  --warm: #fff8e7;
  --shadow: 0 18px 45px rgba(28, 52, 89, 0.10);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  line-height: 1.65;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(29, 95, 209, 0.08), transparent 32rem),
    linear-gradient(180deg, #f8fbff 0%, var(--bg) 38%, #ffffff 100%);
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
code { background: #edf2f8; padding: 2px 7px; border-radius: 7px; font-size: 0.92em; }

.site-header {
  color: white;
  background:
    radial-gradient(circle at 20% 20%, rgba(144, 190, 255, 0.26), transparent 24rem),
    radial-gradient(circle at 80% 10%, rgba(90, 220, 255, 0.16), transparent 22rem),
    linear-gradient(135deg, #081933 0%, #123e7c 48%, #1e68d8 100%);
  overflow: hidden;
}
.nav {
  max-width: 1160px;
  margin: 0 auto;
  padding: 22px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 850;
  color: white;
  font-size: 1.2rem;
  letter-spacing: 0.02em;
}
.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 11px;
  display: inline-grid;
  place-items: center;
  background: rgba(255,255,255,0.16);
  border: 1px solid rgba(255,255,255,0.24);
}
.nav-links { display: flex; gap: 10px; flex-wrap: wrap; justify-content: flex-end; }
.nav-links a {
  color: #eaf2ff;
  font-size: 0.92rem;
  padding: 7px 10px;
  border-radius: 999px;
}
.nav-links a:hover { background: rgba(255,255,255,0.10); text-decoration: none; }
.hero {
  max-width: 1160px;
  margin: 0 auto;
  padding: 78px 24px 96px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 42px;
  align-items: end;
}
.eyebrow, .section-kicker {
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.78rem;
  font-weight: 800;
  margin: 0 0 12px;
}
.eyebrow { color: #c9e0ff; }
.hero h1 {
  max-width: 850px;
  font-size: clamp(2.5rem, 6vw, 5.3rem);
  line-height: 0.98;
  letter-spacing: -0.055em;
  margin: 0;
}
.hero-text {
  max-width: 760px;
  font-size: 1.22rem;
  color: #e7f0ff;
  margin: 26px 0 0;
}
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 34px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 18px;
  border-radius: 999px;
  font-weight: 800;
  box-shadow: 0 10px 22px rgba(0,0,0,0.12);
}
.button.primary { background: white; color: var(--primary-dark); }
.button.secondary { border: 1px solid rgba(255,255,255,0.55); color: white; box-shadow: none; }
.hero-panel {
  padding: 22px;
  border: 1px solid rgba(255,255,255,0.22);
  border-radius: 24px;
  background: rgba(255,255,255,0.10);
  backdrop-filter: blur(12px);
  box-shadow: 0 20px 60px rgba(0,0,0,0.20);
}
.panel-row {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(255,255,255,0.18);
}
.panel-row:last-child { border-bottom: 0; }
.panel-row span { color: #cfe2ff; font-size: 0.92rem; }
.panel-row strong { font-size: 1.12rem; }

.section { max-width: 1160px; margin: 0 auto; padding: 72px 24px; }
.section.alt {
  background: rgba(255,255,255,0.82);
  max-width: none;
  padding-left: max(24px, calc((100vw - 1160px) / 2 + 24px));
  padding-right: max(24px, calc((100vw - 1160px) / 2 + 24px));
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.section-heading { max-width: 780px; margin-bottom: 22px; }
.section-kicker { color: var(--primary); }
.section h2 {
  font-size: clamp(2rem, 4vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -0.035em;
  margin: 0;
  color: #0f2038;
}
.section h3 { margin-top: 0; color: #173b68; font-size: 1.28rem; }
.section h4 { margin: 0 0 8px; color: #173b68; }
.lead { max-width: 920px; font-size: 1.08rem; color: #3c485c; }

.stats-grid, .cards, .protocol, .audio-grid { display: grid; gap: 18px; }
.stats-grid { grid-template-columns: repeat(4, minmax(140px, 1fr)); margin-top: 34px; }
.cards { grid-template-columns: repeat(2, minmax(260px, 1fr)); margin-top: 30px; }
.protocol { grid-template-columns: repeat(4, minmax(160px, 1fr)); margin-top: 30px; }
.audio-grid { grid-template-columns: repeat(5, minmax(150px, 1fr)); margin-top: 20px; }

.stat-card, .card, .protocol > div, .notice, .example-card, .audio-item {
  background: rgba(255,255,255,0.92);
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 24px;
  box-shadow: var(--shadow);
}
.stat-card { min-height: 150px; }
.stat-number { display: block; font-size: 2.25rem; font-weight: 900; color: var(--primary); letter-spacing: -0.04em; }
.stat-label, .small { color: var(--muted); }
.card ul, .terms-list { padding-left: 22px; }
.feature-card { position: relative; overflow: hidden; }
.feature-card::after {
  content: "";
  position: absolute;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background: var(--primary-soft);
  right: -70px;
  top: -90px;
  z-index: 0;
}
.feature-card > * { position: relative; z-index: 1; }
.card-badge, .pill, .step {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  border-radius: 999px;
  font-weight: 800;
}
.card-badge, .pill { padding: 6px 11px; font-size: 0.8rem; color: var(--primary-dark); background: var(--primary-soft); margin-bottom: 14px; }
.step { color: var(--primary); background: var(--primary-soft); padding: 4px 9px; margin-bottom: 12px; font-size: 0.78rem; }
.notice { background: var(--accent); margin: 24px 0; display: grid; gap: 8px; }
.notice.anonymous { background: var(--warm); border-color: #f2dfaa; }
.example-card { margin-top: 24px; }
.example-card.soft { background: #fbfdff; box-shadow: none; }
.example-header { display: flex; justify-content: space-between; align-items: start; gap: 18px; flex-wrap: wrap; }
.audio-item { padding: 18px; box-shadow: none; background: #fbfdff; }
.audio-item audio { width: 100%; margin: 10px 0 6px; }
.bibtex {
  background: #0b1424;
  color: #e6edf7;
  overflow-x: auto;
  padding: 20px;
  border-radius: 18px;
  font-size: 0.92rem;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.06);
}
.contact-email { font-size: 1.15rem; font-weight: 800; }
.small { font-size: 0.92rem; }
.footer {
  text-align: center;
  color: #d7e5ff;
  background: #10243d;
  padding: 38px 20px;
  font-size: 0.95rem;
}

@media (max-width: 980px) {
  .hero { grid-template-columns: 1fr; padding-top: 56px; }
  .hero-panel { max-width: 520px; }
  .stats-grid, .protocol { grid-template-columns: repeat(2, minmax(180px, 1fr)); }
  .audio-grid { grid-template-columns: repeat(2, minmax(220px, 1fr)); }
}
@media (max-width: 720px) {
  .nav { align-items: flex-start; flex-direction: column; }
  .nav-links { justify-content: flex-start; }
  .stats-grid, .cards, .protocol, .audio-grid { grid-template-columns: 1fr; }
  .hero { padding-bottom: 68px; }
  .section { padding: 56px 20px; }
}