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

:root {
  --bg: #0d1117;
  --surface: #161b22;
  --surface-2: #1c2128;
  --border: #30363d;
  --text: #c9d1d9;
  --text-bright: #f0f6fc;
  --text-muted: #8b949e;
  --accent: #58a6ff;
  --accent-bright: #79b8ff;
  --green: #56d364;
  --amber: #ffa657;
  --red: #ff7b72;
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.55;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

code {
  font-family: "Menlo", "Monaco", monospace;
  font-size: 0.9em;
  background: var(--surface);
  padding: 1px 6px;
  border-radius: 4px;
  border: 1px solid var(--border);
}

/* ---------- header ---------- */
.site-header {
  padding: 14px 28px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(8px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 600;
  color: var(--text-bright);
}
.brand:hover { text-decoration: none; }
.brand .diamond { color: var(--accent); font-size: 18px; line-height: 1; }
.brand-name { letter-spacing: 0.3px; }

.site-header nav { display: flex; gap: 22px; }
.site-header nav a { color: var(--text-muted); font-size: 13px; }
.site-header nav a:hover { color: var(--text-bright); text-decoration: none; }

/* ---------- hero ---------- */
.hero {
  padding: 80px 28px 56px;
  max-width: 920px;
  margin: 0 auto;
  width: 100%;
}

.eyebrow {
  color: var(--accent);
  font-size: 11px;
  letter-spacing: 1.6px;
  text-transform: uppercase;
  font-family: "Menlo", "Monaco", monospace;
  margin-bottom: 18px;
}

.hero h1 {
  font-size: clamp(28px, 5vw, 46px);
  color: var(--text-bright);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.5px;
  margin-bottom: 22px;
}

.subhead {
  font-size: 17px;
  color: var(--text);
  max-width: 740px;
  margin-bottom: 32px;
}

.hero-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 11px 20px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 120ms;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--accent); color: #0d1117; }
.btn-primary:hover { background: var(--accent-bright); }
.btn-secondary {
  background: transparent;
  color: var(--text-bright);
  border-color: var(--border);
}
.btn-secondary:hover { background: var(--surface); }

/* ---------- sections ---------- */
section.demo-section,
section.video-section,
section.features,
section.stack {
  padding: 40px 28px;
  max-width: 1140px;
  margin: 0 auto;
  width: 100%;
}

section h2 {
  color: var(--text-bright);
  font-size: 24px;
  margin-bottom: 12px;
  font-weight: 600;
  letter-spacing: -0.2px;
}

.lede {
  color: var(--text-muted);
  margin-bottom: 24px;
  font-size: 15px;
  max-width: 740px;
}

/* ---------- demo iframe ---------- */
.iframe-wrap {
  background: #000;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  aspect-ratio: 16/9;
  min-height: 480px;
  position: relative;
}

.iframe-wrap iframe {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}

.iframe-fallback {
  position: absolute;
  inset: 0;
  background: var(--surface);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 40px;
  text-align: center;
}
.iframe-fallback.hidden { display: none; }
.iframe-fallback h3 {
  color: var(--text-bright);
  font-size: 20px;
  margin-bottom: 12px;
  font-weight: 600;
}
.iframe-fallback p {
  color: var(--text-muted);
  margin-bottom: 16px;
  max-width: 520px;
}
.iframe-fallback ul { list-style: none; max-width: 520px; }
.iframe-fallback ul li { margin: 6px 0; }
.iframe-fallback ul a { color: var(--accent); }

/* ---------- video ---------- */
.video-wrap {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  aspect-ratio: 16/9;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 320px;
  overflow: hidden;
}
.video-wrap iframe { width: 100%; height: 100%; border: none; }
.video-placeholder {
  color: var(--text-muted);
  font-style: italic;
}

/* ---------- features ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 12px;
}

.feature {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 22px;
  transition: border-color 120ms, transform 120ms;
}
.feature:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}
.feature h3 {
  color: var(--text-bright);
  font-size: 16px;
  margin-bottom: 8px;
  font-weight: 600;
}
.feature p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.55;
}

/* ---------- stack section ---------- */
.stack-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 8px;
  margin-top: 8px;
}
.stack-list li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 14px 16px;
  font-size: 14px;
  color: var(--text-muted);
}
.stack-list li strong {
  color: var(--text-bright);
  font-weight: 600;
}

/* ---------- footer ---------- */
.site-footer {
  padding: 32px 28px;
  border-top: 1px solid var(--border);
  margin-top: auto;
  text-align: center;
}
.site-footer p { color: var(--text); }
.site-footer .muted {
  color: var(--text-muted);
  font-size: 12px;
  margin-top: 6px;
}

/* ---------- small screens ---------- */
@media (max-width: 600px) {
  .hero { padding: 48px 20px 32px; }
  .site-header { padding: 12px 16px; }
  .site-header nav { gap: 14px; }
  section.demo-section,
  section.video-section,
  section.features,
  section.stack {
    padding: 32px 20px;
  }
  .iframe-wrap { min-height: 360px; }
}