:root {
  --bg: #0d0f12;
  --card: #151922;
  --text: #e8ecf1;
  --muted: #9aa7b2;
  --accent: #66d28e;
  --accent-fg: #0a1b12;
  --border: #243041;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: radial-gradient(1200px 600px at 10% -10%, #16202e 0%, transparent 60%),
              radial-gradient(1000px 500px at 100% 0%, #101826 0%, transparent 60%),
              var(--bg);
  line-height: 1.6;
}

.container {
  width: min(100%, 960px);
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(13, 15, 18, 0.6);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-content { display: flex; align-items: center; justify-content: space-between; padding: 12px 0; }
.brand { display: flex; align-items: center; gap: 12px; }
.brand h1 { font-size: 20px; margin: 0; letter-spacing: 0.2px; }
.logo { width: 28px; height: 28px; filter: saturate(1.1) drop-shadow(0 0 8px rgba(102,210,142,.25)); }

.header-nav a { color: var(--text); text-decoration: none; margin-left: 16px; font-weight: 600; }
.header-nav a:hover { color: var(--accent); }

.hero { padding: 48px 0 8px; text-align: left; }
.hero h2 { font-size: 32px; margin: 0 0 8px; }
.hero p { color: var(--muted); margin: 0; }

.section { padding: 32px 0; }
.section h3 { margin-top: 0; font-size: 22px; }

details { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 12px 16px; margin: 12px 0; }
details > summary { cursor: pointer; font-weight: 600; }
details > p { margin: 8px 0 0; color: var(--muted); }

ul { padding-left: 18px; }
li { margin: 6px 0; }

a { color: var(--accent); }
a:hover { color: #8ae3ab; }

.site-footer { border-top: 1px solid var(--border); margin-top: 24px; }
.site-footer .container { padding: 16px 0 40px; display: flex; align-items: center; justify-content: space-between; color: var(--muted); }

@media (max-width: 640px) {
  .header-nav { display: none; }
  .hero { padding-top: 32px; }
  .hero h2 { font-size: 26px; }
}