/* OpenSpecGUI 官网 — 简洁、可读，无重型 UI 库 */
:root {
  --bg: #fafafa;
  --fg: #1a1a1a;
  --muted: #555;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --border: #e5e7eb;
  --card: #fff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 18px;
  line-height: 1.6;
  color: var(--fg);
  background: var(--bg);
}

.hero {
  text-align: center;
  padding: 3rem 1.5rem 2rem;
  max-width: 640px;
  margin: 0 auto;
}

.hero-icon {
  display: block;
  margin: 0 auto 1rem;
}

.hero h1 {
  font-size: 2.25rem;
  font-weight: 700;
  margin: 0 0 0.5rem;
  letter-spacing: -0.02em;
}

.tagline {
  font-size: 1.125rem;
  color: var(--muted);
  margin: 0;
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}

.section {
  margin-bottom: 2.5rem;
}

.section h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 0.75rem;
  color: var(--fg);
}

.section p,
.section ul {
  margin: 0 0 0.5rem;
  color: var(--muted);
}

.section ul {
  padding-left: 1.25rem;
}

.section li {
  margin-bottom: 0.5rem;
}

.download-section {
  text-align: center;
  padding: 2rem 0;
  border-top: 1px solid var(--border);
}

.meta {
  font-size: 0.9375rem;
  color: var(--muted);
  margin-bottom: 1rem;
}

.download-btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  background: var(--accent);
  border-radius: 8px;
  text-decoration: none;
  transition: background 0.15s;
}

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

.hint {
  font-size: 0.875rem;
  color: var(--muted);
  margin-top: 1rem;
}

footer {
  text-align: center;
  padding: 1.5rem;
  font-size: 0.875rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
}

footer p {
  margin: 0;
}