:root {
  --text: #1a1a1a;
  --muted: #5a6472;
  --border: #e6e8eb;
  --accent: #1f6feb;
  --bg: #ffffff;
  --bg-soft: #f7f8fa;
  --maxw: 720px;
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
    Arial, "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.brand {
  font-weight: 700;
  font-size: 18px;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.brand span {
  color: var(--muted);
  font-weight: 500;
}

.nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
}

.nav a:hover {
  color: var(--accent);
}

.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px 24px;
}

main.wrap {
  padding-top: 40px;
  padding-bottom: 56px;
}

h1 {
  font-size: 30px;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}

h2 {
  font-size: 21px;
  line-height: 1.3;
  margin: 36px 0 12px;
}

p {
  margin: 0 0 16px;
}

ul {
  margin: 0 0 16px;
  padding-left: 22px;
}

li {
  margin: 0 0 8px;
}

a {
  color: var(--accent);
}

.lead {
  font-size: 19px;
  color: var(--muted);
}

.updated {
  display: inline-block;
  font-size: 14px;
  color: var(--muted);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 4px 12px;
  margin-bottom: 24px;
}

.callout {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px 20px;
  margin: 24px 0;
}

.callout p:last-child {
  margin-bottom: 0;
}

.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin: 28px 0 8px;
}

.card {
  display: block;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px 20px;
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.card:hover {
  border-color: var(--accent);
  box-shadow: 0 1px 0 var(--border);
}

.card .card-title {
  font-weight: 600;
  font-size: 17px;
  margin-bottom: 4px;
}

.card .card-desc {
  color: var(--muted);
  font-size: 15px;
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 14px;
}

.site-footer .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  padding-top: 22px;
  padding-bottom: 28px;
}

.site-footer a {
  color: var(--muted);
}

@media (max-width: 600px) {
  body {
    font-size: 16px;
  }
  h1 {
    font-size: 25px;
  }
  h2 {
    font-size: 19px;
  }
}