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

body {
  font-family: system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: #222;
  background: #f5f5f5;
  display: flex;
  flex-direction: column;
  height: 100vh;
}

header {
  background: #1a1a2e;
  color: #eee;
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: baseline;
  gap: 1rem;
  flex-shrink: 0;
}

header h1 { font-size: 1.2rem; font-weight: 600; }
header span { font-size: 0.9rem; color: #aaa; }

#shell {
  display: flex;
  flex: 1;
  overflow: hidden;
}

nav {
  width: 180px;
  flex-shrink: 0;
  background: #fff;
  border-right: 1px solid #ddd;
  padding: 1rem 0;
  overflow-y: auto;
}

nav a {
  display: block;
  padding: 0.5rem 1.25rem;
  color: #444;
  text-decoration: none;
  font-size: 0.9rem;
}

nav a:hover { background: #f0f0f0; }
nav a.active { background: #e8e8f0; color: #1a1a2e; font-weight: 500; }

main {
  flex: 1;
  overflow-y: auto;
  padding: 2rem;
  background: #fff;
}

/* Content typography — your HTML files just use bare tags */
main h1 { font-size: 1.5rem; margin-bottom: 1rem; border-bottom: 1px solid #eee; padding-bottom: 0.5rem; }
main h2 { font-size: 1.2rem; margin: 1.5rem 0 0.5rem; }
main p  { margin-bottom: 0.8rem; }
main ul, main ol { margin: 0.5rem 0 0.8rem 1.5rem; }
main a  { color: #2a5aad; }
main code { font-family: monospace; background: #f4f4f4; padding: 1px 5px; border-radius: 3px; }
main pre  { background: #f4f4f4; padding: 1rem; overflow-x: auto; border-radius: 4px; margin-bottom: 1rem; }