:root {
  --bg: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --text-secondary: #6e6e73;
  --accent: #007aff;
  --accent-dark: #0a84ff;
  --border: #d2d2d7;
  --radius: 12px;
  --max-width: 760px;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --card: #1c1c1e;
    --text: #f5f5f7;
    --text-secondary: #98989d;
    --border: #38383a;
    --accent: #0a84ff;
  }
}

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px 20px 64px;
}

header {
  text-align: center;
  padding: 48px 0 32px;
}

header .app-name {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

header .subtitle {
  color: var(--text-secondary);
  font-size: 1.05rem;
  margin-top: 8px;
}

nav.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin: 24px 0 32px;
}

nav.site-nav a {
  padding: 8px 16px;
  border-radius: 20px;
  background: var(--card);
  border: 1px solid var(--border);
  font-size: 0.875rem;
  color: var(--text);
  text-decoration: none;
}

nav.site-nav a:hover,
nav.site-nav a.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  text-decoration: none;
}

.lang-switch {
  text-align: center;
  margin-bottom: 24px;
}

.lang-switch button {
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 14px;
  margin: 0 4px;
  cursor: pointer;
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-family: var(--font);
}

.lang-switch button.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.card {
  background: var(--card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 28px 24px;
  margin-bottom: 20px;
}

.card h2 {
  font-size: 1.35rem;
  font-weight: 600;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 20px 0 8px;
}

.card p, .card li {
  color: var(--text);
  margin-bottom: 12px;
}

.card ul, .card ol {
  padding-left: 1.4em;
  margin-bottom: 12px;
}

.card li { margin-bottom: 6px; }

.meta {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 20px;
}

footer {
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.8125rem;
  padding: 32px 0;
  border-top: 1px solid var(--border);
  margin-top: 16px;
}

footer a { color: var(--text-secondary); }

.grid-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 8px;
}

.grid-links a.card-link {
  display: block;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.2s;
}

.grid-links a.card-link:hover {
  border-color: var(--accent);
  text-decoration: none;
}

.grid-links a.card-link .icon { font-size: 1.5rem; margin-bottom: 8px; }
.grid-links a.card-link .title { font-weight: 600; font-size: 1rem; }
.grid-links a.card-link .desc { color: var(--text-secondary); font-size: 0.875rem; margin-top: 4px; }

[lang-section] { display: none; }
[lang-section].visible { display: block; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
  margin: 12px 0;
}

th, td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
}

th { font-weight: 600; color: var(--text-secondary); font-size: 0.8125rem; }