/* =========================================================================
   runtime.starseas.org — 运行时内核站
   ========================================================================= */

.hero {
  padding: 120px 0 64px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.hero-badge {
  display: inline-block;
  padding: 6px 14px;
  border: 1px solid var(--border);
  border-radius: 100px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: #fff;
  margin-bottom: 16px;
}

.hero-title .accent { color: #22C55E; }

.hero-subtitle {
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-dim);
  max-width: 540px;
  margin: 0 auto 32px;
}

.hero-install {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  margin-bottom: 8px;
}

.install-command {
  font-family: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  color: var(--text);
}

.hero-install .copy-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-dim);
  cursor: pointer;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-family: inherit;
  transition: color 0.15s, border-color 0.15s;
}

.hero-install .copy-btn:hover {
  color: var(--accent-light);
  border-color: var(--accent);
}

.install-sub {
  font-size: 13px;
  color: var(--text-muted);
  font-family: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
}

/* --- Gaps Grid --- */
.gaps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.gap-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 20px;
}

.gap-icon {
  color: #22C55E;
  margin-bottom: 12px;
}

.gap-card h3 {
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 8px;
}

.gap-card p {
  font-size: 13px;
  color: var(--text-dim);
  line-height: 1.6;
}

/* --- Architecture Layers --- */
.section-arch {
  background: linear-gradient(180deg, rgba(34, 197, 94, 0.02) 0%, transparent 100%);
}

.layers {
  max-width: 640px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.layer {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.layer-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  padding: 0;
  background: none;
  border: none;
}

.layer-sub {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.layer-num {
  font-size: 11px;
  font-weight: 700;
  color: #22C55E;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  flex-shrink: 0;
  min-width: 52px;
}

.layer-name {
  font-size: 13px;
  color: var(--text);
  font-weight: 500;
  flex: 1;
}

.layer-desc {
  font-size: 12px;
  color: var(--text-muted);
  flex-shrink: 0;
}

/* --- Install Steps --- */
.section-install {
  border-top: 1px solid var(--border);
}

.rt-steps {
  max-width: 600px;
  margin: 0 auto;
  display: grid;
  gap: 12px;
}

.rt-step {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px 18px;
}

.rt-step code {
  font-family: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  color: var(--text);
}

.rt-step-accent {
  border-color: rgba(34, 197, 94, 0.2);
  background: rgba(34, 197, 94, 0.04);
}

.rt-step-accent code {
  color: #22C55E;
  font-weight: 500;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .hero { padding: 90px 0 48px; }

  .gaps-grid { grid-template-columns: 1fr; }
  .layer { flex-wrap: wrap; gap: 6px; }
  .layer-split { grid-template-columns: 1fr; }
  .layer-num { min-width: 40px; }
}