:root {
  color-scheme: light dark;
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #111827;
  --muted: #64748b;
  --accent: #2563eb;
  --border: color-mix(in srgb, var(--text) 12%, transparent);
}

body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  padding: 28px 16px;
}

main {
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: clamp(20px, 5vw, 40px);
}

.mark {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  margin: 28px 0 14px;
  color: #ffffff;
  background: var(--accent);
  font-weight: 800;
}

.back,
a {
  color: var(--accent);
}

.back {
  font-weight: 600;
  text-decoration: none;
}

h1 {
  margin: 0;
  font-size: clamp(28px, 6vw, 40px);
  line-height: 1.08;
}

h2 {
  margin: 0 0 8px;
  font-size: 19px;
}

p,
li {
  font-size: 16px;
  line-height: 1.6;
}

p {
  margin: 0;
}

.updated {
  margin-top: 10px;
  color: var(--muted);
}

section {
  margin-top: 28px;
}

ul {
  margin: 0 0 12px;
  padding-left: 22px;
}

li + li {
  margin-top: 6px;
}

code {
  padding: 2px 5px;
  border-radius: 5px;
  background: color-mix(in srgb, var(--surface) 82%, var(--accent));
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f172a;
    --surface: #111827;
    --text: #f8fafc;
    --muted: #94a3b8;
    --accent: #60a5fa;
  }
}