:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --ink: #101828;
  --muted: #5f6b7a;
  --line: #d9e0ea;
  --card: #ffffff;
  --accent: #2563eb;
  --accent-dark: #1e40af;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  color: var(--accent-dark);
  text-decoration: underline;
}

.shell {
  width: min(920px, calc(100% - 32px));
  margin: 0 auto;
}

header {
  padding: 40px 0 24px;
}

.brand {
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

h1 {
  margin: 12px 0 12px;
  font-size: clamp(34px, 6vw, 64px);
  line-height: 1;
  letter-spacing: 0;
}

h2 {
  margin: 34px 0 10px;
  font-size: 24px;
}

h3 {
  margin: 24px 0 8px;
  font-size: 18px;
}

p,
li {
  font-size: 17px;
}

.lead {
  max-width: 720px;
  color: var(--muted);
  font-size: 20px;
}

.card {
  margin: 18px 0;
  padding: 24px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 16px;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
}

.button:hover {
  background: var(--accent-dark);
  color: #fff;
  text-decoration: none;
}

.meta {
  color: var(--muted);
  font-size: 14px;
}

footer {
  margin-top: 48px;
  padding: 24px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 18px;
}

ul {
  padding-left: 22px;
}

code {
  padding: 2px 5px;
  border-radius: 5px;
  background: #eef2f7;
}