:root {
  --bg: #f6f5fb;
  --surface: #ffffff;
  --text: #1c1b29;
  --muted: #5e5c75;
  --accent: #4b3fa8;
  --rule: #e3e1ef;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f0d1f;
    --surface: #1a1830;
    --text: #ecebf5;
    --muted: #a9a6c4;
    --accent: #ffd27d;
    --rule: #2c2947;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 -apple-system, BlinkMacSystemFont, "PingFang TC", "Helvetica Neue", sans-serif;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 20px 72px;
}

header { margin-bottom: 32px; }
header img { width: 72px; height: 72px; border-radius: 16px; }
h1 { font-size: 32px; line-height: 1.2; margin: 16px 0 4px; }
h2 { font-size: 22px; margin: 40px 0 8px; }
h3 { font-size: 18px; margin: 28px 0 4px; }
p, li { color: var(--text); }
.muted { color: var(--muted); }
a { color: var(--accent); }

nav.lang { display: flex; gap: 12px; margin-top: 12px; }
nav.lang a {
  padding: 4px 12px;
  border: 1px solid var(--rule);
  border-radius: 999px;
  text-decoration: none;
  background: var(--surface);
}

section.lang-block {
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 20px;
  padding: 8px 28px 24px;
  margin-top: 24px;
}

footer { margin-top: 40px; font-size: 14px; color: var(--muted); }

@media (max-width: 480px) {
  section.lang-block { padding: 4px 18px 18px; }
  h1 { font-size: 28px; }
}