:root {
  color-scheme: light dark;
  --ink: #0b1230;
  --muted: #556078;
  --line: rgba(55, 72, 110, 0.18);
  --card: rgba(255, 255, 255, 0.88);
  --blue: #1769ff;
  --mint: #168e75;
  --canvas: #f4f7fc;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font: 17px/1.62 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 92% 4%, rgba(47, 175, 145, 0.16), transparent 30rem),
    radial-gradient(circle at 5% 8%, rgba(23, 105, 255, 0.13), transparent 28rem),
    var(--canvas);
}

main { width: min(820px, calc(100% - 32px)); margin: 0 auto; padding: 48px 0 72px; }
header, section, footer {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: clamp(22px, 4vw, 42px);
  margin-bottom: 18px;
  box-shadow: 0 18px 52px rgba(21, 36, 72, 0.08);
}

.brand { font-size: 1.1rem; font-weight: 800; letter-spacing: -0.02em; }
.brand span { color: var(--mint); }
h1 { font-size: clamp(2rem, 6vw, 3.4rem); line-height: 1.05; letter-spacing: -0.05em; margin: 1rem 0; }
h2 { margin: 0 0 0.65rem; letter-spacing: -0.025em; }
h3 { margin-bottom: 0.35rem; }
p, li { color: var(--muted); }
a { color: var(--blue); font-weight: 650; }
nav { display: flex; flex-wrap: wrap; gap: 8px 16px; margin-top: 1.4rem; }
.notice { border-left: 5px solid var(--mint); padding-left: 18px; }
.danger { border-left-color: #d34545; }
.language { font-size: 0.9rem; color: var(--muted); }
footer { font-size: 0.92rem; }

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #f5f7ff;
    --muted: #c2c9da;
    --line: rgba(205, 215, 239, 0.18);
    --card: rgba(17, 25, 49, 0.91);
    --canvas: #070d20;
  }
}