@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,600;1,8..60,400&family=Source+Code+Pro:wght@400;500&display=swap');

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #fdfdfc;
  --text: #1a1a1a;
  --muted: #6b6b6b;
  --border: #e0ddd8;
  --accent: #2563eb;
  --max-width: 680px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.0625rem;
  line-height: 1.75;
  padding: 3rem 1.5rem;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
}

header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

header h1 {
  font-size: 1.75rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text);
}

header p.subtitle {
  margin-top: 0.4rem;
  color: var(--muted);
  font-size: 0.95rem;
  font-family: 'Source Code Pro', monospace;
}

main {
  color: var(--text);
}

nav {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

nav a {
  color: var(--accent);
  text-decoration: none;
  font-size: 1rem;
  border-bottom: 1px solid transparent;
  display: inline-block;
  transition: border-color 0.15s;
}

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

.back {
  display: inline-block;
  font-family: 'Source Code Pro', monospace;
  font-size: 0.85rem;
  color: var(--muted);
  text-decoration: none;
  margin-bottom: 2rem;
}

.back:hover {
  color: var(--text);
}