:root {
  --font-sans: "Inter", "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
  --color-text: #1f2933;
  --color-muted: #52606d;
  --color-accent: #2b6cb0;
  --color-bg: #f8fafc;
  --color-border: #e2e8f0;
}

* {
  box-sizing: border-box;
}

html {
  font-size: 18px;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

header {
  background: #fff;
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 1.5rem;
  display: flex;
  align-items: baseline;
  gap: 1.5rem;
  flex-wrap: wrap;
}

header h1 {
  margin: 0;
  font-size: 1.35rem;
  font-weight: 600;
}

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

nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

nav a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
}

nav a:hover {
  text-decoration: underline;
}

main {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1.5rem;
}

h1, h2, h3, h4 {
  line-height: 1.25;
}

h1 {
  font-size: 2rem;
}

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

footer {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1rem 1.5rem 2.5rem;
  color: var(--color-muted);
  font-size: 0.9rem;
}