:root {
  color-scheme: light dark;
  --bg: #f7f7fb;
  --card: #ffffff;
  --text: #202334;
  --muted: #62687d;
  --line: #dfe1eb;
  --accent: #5b5ce2;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); line-height: 1.65; }
header, main, footer { width: min(900px, calc(100% - 32px)); margin-inline: auto; }
header { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 28px 0; }
.brand { display: flex; align-items: center; gap: 12px; color: inherit; text-decoration: none; font-size: 1.25rem; }
.mark { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 13px; background: var(--accent); color: #fff; font-weight: 800; }
nav { display: flex; align-items: center; flex-wrap: wrap; gap: 16px; }
nav a, main a, footer a { color: var(--accent); }
.language-link { padding: 5px 10px; border: 1px solid var(--line); border-radius: 999px; text-decoration: none; font-size: .85rem; font-weight: 700; }
main { padding: clamp(24px, 5vw, 56px); border: 1px solid var(--line); border-radius: 24px; background: var(--card); box-shadow: 0 22px 60px rgba(43, 45, 90, .08); }
h1 { margin: .2em 0 .35em; font-size: clamp(2rem, 5vw, 3.4rem); line-height: 1.05; letter-spacing: -.045em; }
h2 { margin-top: 2em; font-size: 1.35rem; }
.lead { color: var(--muted); font-size: 1.15rem; }
.notice { padding: 14px 18px; border-left: 4px solid var(--accent); border-radius: 8px; background: color-mix(in srgb, var(--accent) 8%, var(--card)); }
footer { padding: 28px 0 48px; color: var(--muted); font-size: .9rem; text-align: center; }

@media (prefers-color-scheme: dark) {
  :root { --bg: #101119; --card: #181a25; --text: #f1f2fa; --muted: #aeb2c7; --line: #303345; }
}

@media (max-width: 620px) {
  header { align-items: flex-start; flex-direction: column; }
  main { border-radius: 18px; }
}