:root {
  color-scheme: light dark;
  --brand: #0066ff;
  --brand-fill: #0066ff;
  --brand-deep: #0243c9;
  --brand-soft: rgba(0, 102, 255, 0.10);
  --background: #f5f7fb;
  --surface: #ffffff;
  --text: #121722;
  --secondary: #5d6676;
  --border: rgba(18, 23, 34, 0.10);
  --shadow: 0 18px 55px rgba(14, 37, 80, 0.08);
}

@media (prefers-color-scheme: dark) {
  :root {
    --brand: #3385ff;
    --brand-fill: #0066ff;
    --brand-deep: #65a0ff;
    --brand-soft: rgba(0, 102, 255, 0.18);
    --background: #080b11;
    --surface: #141820;
    --text: #f4f7fb;
    --secondary: #a7b0bf;
    --border: rgba(255, 255, 255, 0.10);
    --shadow: none;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 50% -10%, var(--brand-soft), transparent 34rem),
    var(--background);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand); }
a:hover { color: var(--brand-deep); }

.page {
  width: min(100% - 32px, 820px);
  margin: 0 auto;
  padding: 48px 0 64px;
}

.header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--brand);
  font-size: 15px;
  font-weight: 750;
  letter-spacing: 0.01em;
}

.brand-mark {
  width: 13px;
  height: 13px;
  border: 3px solid currentColor;
  border-radius: 50%;
  box-shadow: 0 0 0 5px var(--brand-soft);
}

.language-switcher {
  display: inline-flex;
  padding: 3px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
}

.language-switcher button {
  border: 0;
  border-radius: 999px;
  padding: 7px 12px;
  background: transparent;
  color: var(--secondary);
  font: inherit;
  font-size: 14px;
  cursor: pointer;
}

.language-switcher button[aria-pressed="true"] {
  background: var(--brand-fill);
  color: #fff;
  font-weight: 650;
}

main {
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 24px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.hero {
  padding: 44px 48px 34px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(145deg, var(--brand-soft), transparent 65%);
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(2rem, 6vw, 3.25rem);
  line-height: 1.12;
  letter-spacing: -0.035em;
}

.updated {
  margin: 0;
  color: var(--secondary);
  font-size: 14px;
}

.content { padding: 16px 48px 44px; }

section {
  padding-top: 28px;
  scroll-margin-top: 24px;
}

h2 {
  margin: 0 0 10px;
  font-size: 1.18rem;
  line-height: 1.35;
}

p { margin: 0 0 12px; }
ul { margin: 8px 0 14px; padding-left: 1.35rem; }
li + li { margin-top: 8px; }
strong { font-weight: 700; }

.notice {
  margin-top: 20px;
  padding: 16px 18px;
  border-left: 4px solid var(--brand);
  border-radius: 10px;
  background: var(--brand-soft);
}

footer {
  padding: 22px 4px 0;
  color: var(--secondary);
  text-align: center;
  font-size: 13px;
}

[hidden] { display: none !important; }

@media (max-width: 620px) {
  .page { width: min(100% - 20px, 820px); padding-top: 20px; }
  .header { align-items: center; }
  .hero { padding: 32px 22px 26px; }
  .content { padding: 8px 22px 32px; }
  main { border-radius: 18px; }
}