:root {
  --bg: #0a0a08;
  --fg: #e8e4d9;
  --muted: #8a8578;
  --accent: #d4a853;
  --accent2: #c23b22;
  --card: rgba(26, 24, 20, 0.9);
  --border: rgba(212, 168, 83, 0.15);
}

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

body {
  font-family: 'Noto Sans Tamil', 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.8;
}

.container { max-width: 900px; margin: 0 auto; padding: 0 1.5rem; }

header {
  padding: 4rem 0 2rem;
  border-bottom: 1px solid var(--border);
  text-align: center;
}

header h1 {
  font-size: 3rem;
  color: var(--accent);
  letter-spacing: 0.05em;
  margin-bottom: 0.25rem;
}

header .subtitle {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

header .tagline {
  font-size: 0.95rem;
  color: var(--muted);
  opacity: 0.8;
  max-width: 600px;
  margin: 0 auto;
}

main { padding: 3rem 0; }

h2 {
  font-size: 1.5rem;
  color: var(--accent);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--border);
}

.intro { margin-bottom: 2.5rem; }
.intro p { color: var(--fg); font-size: 1.05rem; }

.card-grid {
  display: grid;
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.75rem;
  transition: border-color 0.2s;
}

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

.card-tag {
  display: inline-block;
  background: var(--accent);
  color: var(--bg);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: 3px;
  margin-bottom: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
  color: var(--fg);
}

.card-summary {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 1rem;
  line-height: 1.7;
}

.card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--muted);
}

.card-link {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}

.card-link:hover { text-decoration: underline; }

.about-host { margin-top: 2rem; }
.about-host p { color: var(--muted); }

footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

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

@media (max-width: 640px) {
  header h1 { font-size: 2rem; }
  .card-grid { grid-template-columns: 1fr; }
  .card-meta { flex-direction: column; gap: 0.5rem; }
}

.back-link {
  display: inline-block;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.en-subtitle {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.video-section {
  margin: 2rem 0;
}

.video-wrapper {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.number-grid {
  display: grid;
  gap: 1.5rem;
}

.number-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.75rem;
}

.calc-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.75rem;
}

.research article {
  margin-bottom: 2rem;
}

.en-text {
  color: var(--fg);
  font-size: 1.05rem;
}

.sources ol {
  padding-left: 1.5rem;
}