:root {
  --teal-900: #063b3a;
  --teal-800: #0a4f4d;
  --teal-700: #0e6b67;
  --teal-600: #128882;
  --teal-500: #17a29a;
  --gold-500: #d4a94a;
  --gold-400: #e3bd6b;
  --ink-900: #12201f;
  --ink-700: #3a4f4d;
  --paper-0: #ffffff;
  --paper-50: #f5f9f8;
  --paper-100: #eaf2f1;
  --border: #dbe7e5;
  --radius: 14px;
  --shadow: 0 8px 24px rgba(6, 59, 58, 0.10);
  --shadow-sm: 0 2px 8px rgba(6, 59, 58, 0.08);
  font-size: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink-900);
  background: var(--paper-50);
  line-height: 1.55;
}

img { max-width: 100%; display: block; }

a { color: var(--teal-700); text-decoration: none; }
a:hover { color: var(--teal-500); }

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header / Nav */
#site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--teal-900);
  box-shadow: var(--shadow-sm);
}

.nav-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1120px;
  margin: 0 auto;
  padding: 12px 20px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.2px;
}

.nav-brand .dot { color: var(--gold-400); }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 8px;
  color: #fff;
  font-size: 1.1rem;
  padding: 6px 10px;
  cursor: pointer;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
}

.nav-links a {
  color: rgba(255,255,255,0.85);
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 0.92rem;
  font-weight: 600;
  white-space: nowrap;
}

.nav-links a:hover { background: rgba(255,255,255,0.08); color: #fff; }

.nav-links a.active {
  background: var(--gold-500);
  color: var(--teal-900);
}

.nav-links .nav-sep {
  width: 1px;
  height: 20px;
  background: rgba(255,255,255,0.25);
  margin: 0 6px;
}

@media (max-width: 860px) {
  .nav-toggle { display: inline-block; }
  .nav-links {
    display: none;
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    padding-top: 10px;
  }
  .nav-links.open { display: flex; }
  .nav-links .nav-sep { display: none; }
  .nav-bar { flex-wrap: wrap; }
}

/* Hero */
.hero {
  background:
    radial-gradient(1200px 420px at 15% -10%, rgba(212,169,74,0.18), transparent 60%),
    linear-gradient(135deg, var(--teal-900), var(--teal-700));
  color: #fff;
  padding: 64px 0 56px;
}

.hero .hero-logo {
  display: block;
  width: 200px;
  max-width: 60%;
  height: auto;
  margin-bottom: 22px;
}

.hero .eyebrow {
  display: inline-block;
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.25);
  color: var(--gold-400);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  padding: 5px 12px;
  border-radius: 999px;
  margin-bottom: 18px;
}

.hero h1 {
  font-size: clamp(1.9rem, 4vw, 2.9rem);
  margin: 0 0 14px;
  line-height: 1.15;
}

.hero p.lead {
  font-size: 1.1rem;
  max-width: 640px;
  color: rgba(255,255,255,0.88);
  margin: 0 0 26px;
}

.btn-row { display: flex; flex-wrap: wrap; gap: 12px; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
}

.btn-gold { background: var(--gold-500); color: var(--teal-900); }
.btn-gold:hover { background: var(--gold-400); color: var(--teal-900); }

.btn-outline { border-color: rgba(255,255,255,0.55); color: #fff; }
.btn-outline:hover { background: rgba(255,255,255,0.12); color: #fff; }

.btn-teal { background: var(--teal-600); color: #fff; }
.btn-teal:hover { background: var(--teal-500); color: #fff; }

/* Sections */
section.block { padding: 52px 0; }
section.block.alt { background: var(--paper-100); }

.section-head { margin-bottom: 28px; max-width: 720px; }
.section-head .kicker {
  color: var(--teal-600);
  font-weight: 700;
  font-size: 0.82rem;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  margin-bottom: 6px;
}
.section-head h2 { font-size: clamp(1.4rem, 2.6vw, 1.9rem); margin: 0 0 8px; color: var(--teal-900); }
.section-head p { color: var(--ink-700); margin: 0; }

.grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
}

.grid.cols-5 { grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); }
.grid.cols-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }

.card {
  background: var(--paper-0);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }

.card h3 { margin: 0 0 8px; font-size: 1.05rem; color: var(--teal-900); }
.card p { margin: 0 0 14px; color: var(--ink-700); font-size: 0.92rem; }
.card .card-link { font-weight: 700; font-size: 0.9rem; }

.lang-card {
  text-align: center;
  padding: 26px 16px;
}
.lang-card .flag { font-size: 2.4rem; margin-bottom: 10px; }
.lang-card h3 { margin-bottom: 4px; }
.lang-card span.native { color: var(--ink-700); font-size: 0.85rem; }

.doc-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.doc-list li {
  background: var(--paper-0);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 16px;
}
.doc-list a { font-weight: 600; display: flex; align-items: center; gap: 10px; }
.doc-list .ext {
  font-size: 0.68rem;
  font-weight: 800;
  background: var(--teal-100, var(--paper-100));
  color: var(--teal-700);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2px 6px;
  letter-spacing: 0.4px;
}

.doc-list li.has-video { padding: 14px 16px 16px; }
.doc-list .doc-title {
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  color: var(--ink-900);
}
.inline-video {
  width: 100%;
  max-width: 640px;
  display: block;
  border-radius: 10px;
  background: #000;
}

.event-card {
  background: var(--paper-0);
  border: 1px solid var(--border);
  border-left: 5px solid var(--gold-500);
  border-radius: var(--radius);
  padding: 22px 24px;
  box-shadow: var(--shadow-sm);
}
.event-card h3 { margin: 0 0 6px; color: var(--teal-900); }
.event-card .time { color: var(--teal-600); font-weight: 700; margin-bottom: 10px; }
.event-card ul { margin: 0 0 14px; padding-left: 18px; color: var(--ink-700); }

.event-card.has-media { display: flex; gap: 24px; flex-wrap: wrap; align-items: flex-start; }
.event-card.has-media .event-photo {
  width: 220px;
  max-width: 100%;
  border-radius: 10px;
  object-fit: cover;
  flex-shrink: 0;
}
.event-card.has-media .event-body { flex: 1; min-width: 260px; }
.event-speaker { color: var(--ink-700); font-size: 0.92rem; margin: 0 0 14px; }

.tech-list { list-style: none; margin: 14px 0; padding: 0; display: grid; gap: 8px; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }
.tech-list li { font-size: 0.88rem; color: var(--ink-700); }
.tech-list b { color: var(--teal-800); }

.event-video-embed {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
  margin: 18px 0;
  border-radius: 10px;
  overflow: hidden;
  background: #000;
}
.event-video-embed iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.event-price-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.event-price-row .price { font-size: 1.3rem; font-weight: 800; color: var(--teal-800); }
.event-price-row .price span { display: block; font-size: 0.75rem; font-weight: 500; color: var(--ink-700); }

.video-grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
}

.video-card {
  background: var(--paper-0);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.video-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.video-card .thumb-wrap { position: relative; background: #000; }
.video-card img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.video-card .play {
  position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 2.2rem; text-shadow: 0 2px 6px rgba(0,0,0,0.6); opacity: 0.9;
}
.video-card .vc-body { padding: 12px 14px; }
.video-card h4 { margin: 0; font-size: 0.92rem; line-height: 1.35; color: var(--ink-900); }
.video-card .vc-date { color: var(--ink-700); font-size: 0.78rem; margin-top: 6px; }

.channel-banner {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
  background: linear-gradient(120deg, var(--teal-800), var(--teal-600));
  color: #fff;
  border-radius: var(--radius);
  padding: 20px 26px;
  margin-bottom: 22px;
}
.channel-banner h3 { margin: 0 0 4px; }
.channel-banner p { margin: 0; color: rgba(255,255,255,0.85); font-size: 0.9rem; }

.science-cat { margin-bottom: 34px; }
.science-cat h3 {
  color: var(--teal-800);
  border-bottom: 2px solid var(--gold-500);
  display: inline-block;
  padding-bottom: 4px;
  margin-bottom: 14px;
}
.science-cat ul { margin: 0; padding-left: 20px; }
.science-cat li { margin-bottom: 8px; }
.science-cat li a { font-size: 0.94rem; }

.note-box {
  background: var(--paper-100);
  border: 1px dashed var(--teal-500);
  border-radius: 10px;
  padding: 14px 18px;
  font-size: 0.88rem;
  color: var(--ink-700);
  margin: 22px 0;
}

footer#site-footer {
  background: var(--teal-900);
  color: rgba(255,255,255,0.75);
  padding: 40px 0 26px;
  margin-top: 30px;
}
footer#site-footer .foot-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 30px;
  justify-content: space-between;
  margin-bottom: 24px;
}
footer#site-footer h4 { color: #fff; margin: 0 0 12px; font-size: 0.95rem; }
footer#site-footer ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; }
footer#site-footer a { color: rgba(255,255,255,0.75); font-size: 0.9rem; }
footer#site-footer a:hover { color: #fff; }
footer#site-footer .foot-bottom {
  border-top: 1px solid rgba(255,255,255,0.15);
  padding-top: 18px;
  font-size: 0.82rem;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: space-between;
}

.badge {
  display: inline-block;
  background: var(--paper-100);
  color: var(--teal-700);
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 0.78rem;
  font-weight: 700;
  margin-bottom: 12px;
}