:root {
  --bg: #0b1020;
  --panel: #121a33;
  --text: #e8ecff;
  --muted: #aab4d4;
  --brand: #7c9cff;
  --brand-2: #4f6fff;
  --line: #24305a;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "PingFang SC", "Noto Sans CJK SC", sans-serif;
  background: linear-gradient(180deg, #0a0f20 0%, #0f1630 100%);
  color: var(--text);
  line-height: 1.6;
}

.container { width: min(1080px, 92%); margin: 0 auto; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(11, 16, 32, 0.8);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.nav { display: flex; justify-content: space-between; align-items: center; padding: 14px 0; }
.logo { color: var(--text); font-weight: 700; text-decoration: none; letter-spacing: 0.3px; }
nav a { color: var(--muted); text-decoration: none; margin-left: 18px; font-size: 14px; }
nav a:hover { color: var(--text); }

.hero { padding: 68px 0 32px; }
.hero-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 26px; align-items: stretch; }
.tag { color: #9fb3ff; margin-bottom: 10px; font-weight: 600; }
h1 { font-size: clamp(2rem, 5vw, 3.4rem); line-height: 1.1; margin: 0 0 14px; }
.lead { color: var(--muted); font-size: 1.06rem; max-width: 65ch; }
.hero-actions { margin-top: 24px; display: flex; gap: 12px; flex-wrap: wrap; }

.btn {
  border: 1px solid var(--line);
  color: var(--text);
  text-decoration: none;
  padding: 10px 16px;
  border-radius: 10px;
  display: inline-block;
  font-weight: 600;
}
.btn.primary {
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  border-color: transparent;
}

.hero-card, .card, .join-box {
  background: rgba(18, 26, 51, 0.88);
  border: 1px solid var(--line);
  border-radius: 14px;
}

.hero-card { padding: 20px; }
.hero-card h3 { margin: 0 0 12px; }
.hero-card ul { margin: 0; padding-left: 18px; color: var(--muted); }

.section { padding: 54px 0; }
.section.alt { background: rgba(9, 14, 30, 0.6); }
.section h2 { margin-top: 0; font-size: 1.9rem; }
.section p { color: var(--muted); }

.cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; margin-top: 14px; }
.cards.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card { padding: 18px; }
.card h3 { margin: 0 0 6px; }
.card p { margin: 0; }
.muted { color: #90a1d3; font-size: 14px; margin-bottom: 6px !important; }

.join-box {
  padding: 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}

.site-footer { border-top: 1px solid var(--line); padding: 22px 0; margin-top: 18px; }
.footer-row { display: flex; justify-content: space-between; color: var(--muted); font-size: 14px; }

@media (max-width: 920px) {
  .hero-grid { grid-template-columns: 1fr; }
  .cards.three { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 640px) {
  nav { display: none; }
  .cards, .cards.three { grid-template-columns: 1fr; }
  .join-box { flex-direction: column; align-items: flex-start; }
  .footer-row { flex-direction: column; gap: 4px; }
}