:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #17202a;
  --muted: #5d6b7a;
  --border: #d9e0e7;
  --accent: #215f9a;
  --accent-dark: #173f67;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.65;
}

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

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

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

.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  max-width: 960px;
  margin: 0 auto;
  padding: 18px 24px;
}

.brand {
  color: var(--text);
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  font-size: 15px;
}

.nav-links a {
  text-decoration: none;
}

.page {
  flex: 1 0 auto;
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  padding: 44px 24px 56px;
}

.content {
  max-width: 760px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 34px;
}

h1,
h2,
h3 {
  line-height: 1.2;
}

h1 {
  margin: 0 0 18px;
  font-size: 36px;
}

h2 {
  margin: 32px 0 10px;
  font-size: 24px;
}

p,
ul {
  margin: 0 0 18px;
}

ul {
  padding-left: 22px;
}

.site-footer {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px 36px;
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 640px) {
  body {
    font-size: 16px;
  }

  .site-nav {
    align-items: flex-start;
    flex-direction: column;
  }

  .page {
    padding: 28px 16px 40px;
  }

  .content {
    padding: 24px;
  }

  h1 {
    font-size: 30px;
  }
}