/**
 * Critical CSS - Above-the-fold styles
 * 21st.dev-inspired dark zinc theme
 */

:root {
  --bg: #09090b;
  --bg-card: #0c0c0f;
  --bg-subtle: #18181b;
  --bg-elevated: #1c1c20;
  --text: #fafafa;
  --text-muted: #a1a1aa;
  --text-light: #71717a;
  --accent: #fafafa;
  --accent-hover: #e4e4e7;
  --border: #27272a;
  --border-strong: #3f3f46;
  --radius-lg: 12px;
  --radius-md: 8px;
  --radius-sm: 6px;
  --radius-pill: 999px;
  --max-width: 1080px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  line-height: 1.6;
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  margin: 0;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background: var(--bg);
}

.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--accent);
  color: var(--bg);
  padding: 8px 16px;
  text-decoration: none;
  font-weight: 600;
  z-index: 10000;
  border-radius: 0 0 8px 0;
}

.skip-link:focus {
  top: 0;
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

h1, h2, h3, h4 {
  margin: 0;
  letter-spacing: -0.025em;
  color: var(--text);
  font-weight: 600;
}

h1 {
  font-size: clamp(2.4rem, 5vw, 3.2rem);
  line-height: 1.1;
  font-weight: 700;
  letter-spacing: -0.035em;
}

h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.15;
  margin-bottom: 12px;
  letter-spacing: -0.03em;
}

p {
  margin: 0;
  line-height: 1.65;
  color: var(--text-muted);
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-dark {
  padding: 72px 0;
}

.stack-hero {
  text-align: center;
  max-width: 680px;
  margin: 0 auto;
  padding-top: 64px;
  padding-bottom: 16px;
}

.stack-hero p {
  margin-top: 16px;
  font-size: 1.05rem;
  line-height: 1.7;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 14px;
  border-radius: var(--radius-pill);
  background: var(--bg-subtle);
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 500;
  margin-bottom: 20px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  margin-top: 24px;
  min-height: 40px;
  border-radius: var(--radius-md);
  border: none;
  background: var(--accent);
  color: var(--bg);
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  transition: background 0.15s ease;
  text-decoration: none;
}

.btn-primary:hover {
  background: var(--accent-hover);
}

.micro {
  margin-top: 12px;
  font-size: 0.8rem;
  color: var(--text-light);
}

.hidden {
  display: none;
}

@media (max-width: 900px) {
  main { padding-inline: 16px; }
  .btn-primary {
    width: 100%;
    max-width: 380px;
  }
}