:root {
  color-scheme: light dark;
  --background: #f4f8fb;
  --surface: rgba(255, 255, 255, 0.96);
  --text: #112a4b;
  --muted: #65758a;
  --border: #d9e3ec;
  --accent: #0e8f91;
  --accent-dark: #075f75;
  --warning-bg: #fff7df;
  --warning-border: #e7b756;
  --warning-text: #5c4211;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
  line-height: 1.6;
  color: var(--text);
  background:
    radial-gradient(circle at 10% 0%, rgba(14, 143, 145, 0.12), transparent 38rem),
    var(--background);
}

a { color: var(--accent-dark); }
a:hover { color: var(--accent); }

.site-header,
main,
.site-footer {
  width: min(820px, calc(100% - 32px));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 4px 14px;
}

.brand {
  color: var(--text);
  font-size: 1.2rem;
  font-weight: 800;
  text-decoration: none;
  letter-spacing: -0.02em;
}

nav { display: flex; flex-wrap: wrap; gap: 14px; }
nav a { color: var(--muted); font-weight: 650; text-decoration: none; }

main {
  margin-top: 12px;
  padding: clamp(24px, 5vw, 48px);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 28px;
  box-shadow: 0 16px 46px rgba(17, 42, 75, 0.08);
}

h1, h2 { line-height: 1.18; letter-spacing: -0.025em; }
h1 { margin: 0 0 8px; font-size: clamp(2rem, 7vw, 3.2rem); }
h2 { margin: 34px 0 8px; font-size: 1.25rem; }
p, li { font-size: 1.02rem; }
ul { padding-left: 1.3rem; }
.updated, .lede { color: var(--muted); }
.lede { max-width: 62ch; font-size: 1.15rem; }

.notice {
  margin: 26px 0;
  padding: 16px 18px;
  color: var(--warning-text);
  background: var(--warning-bg);
  border: 1px solid var(--warning-border);
  border-radius: 16px;
}

.actions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 14px;
  margin-top: 30px;
}

.action {
  display: block;
  min-height: 110px;
  padding: 18px;
  color: var(--text);
  background: rgba(14, 143, 145, 0.07);
  border: 1px solid rgba(14, 143, 145, 0.24);
  border-radius: 18px;
  text-decoration: none;
}

.action strong { display: block; margin-bottom: 5px; }
.action span { color: var(--muted); }

.site-footer {
  padding: 24px 4px 44px;
  color: var(--muted);
  font-size: 0.9rem;
  text-align: center;
}

@media (prefers-color-scheme: dark) {
  :root {
    --background: #091321;
    --surface: rgba(18, 34, 55, 0.98);
    --text: #edf5fb;
    --muted: #a9b9c9;
    --border: #2a4058;
    --accent: #70dadd;
    --accent-dark: #79dfe1;
    --warning-bg: #3a2b0d;
    --warning-border: #946f28;
    --warning-text: #ffe6a9;
  }

  body { background: radial-gradient(circle at 10% 0%, rgba(112, 218, 221, 0.1), transparent 38rem), var(--background); }
  .action { background: rgba(112, 218, 221, 0.08); border-color: rgba(112, 218, 221, 0.25); }
}