:root {
  --bg: #0d1117;
  --surface: #161b22;
  --surface-soft: #161b22;
  --border: #30363d;
  --text: #c9d1d9;
  --text-muted: #8b949e;
  --accent: #238636;
  --accent-strong: #2ea043;
  --success: #3fb950;
  --error: #f85149;
  --radius: 8px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, SF Mono, Menlo, Consolas, "Liberation Mono", monospace;
  --shadow-soft: none;
  --shadow-card: none;
}

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

html,
body {
  min-height: 100%;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  display: flex;
  flex-direction: column;
}

.site-header {
  padding: 1rem;
  border-bottom: 1px solid var(--border);
}

.site-header-inner {
  width: min(920px, 100%);
  margin: 0 auto;
  padding: 0;
}

.site-header h1 {
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0;
}

.site-header p {
  margin-top: 0.05rem;
  color: var(--text-muted);
  font-size: 0.82rem;
}

.page-main {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 1.25rem 1rem 2rem;
}

.site-footer {
  padding: 1rem;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.78rem;
}

@media (max-width: 640px) {
  .site-header {
    padding: 0.8rem;
  }

  .page-main {
    padding: 1rem 0.8rem 1.4rem;
  }
}