:root { color-scheme: light dark; }
body { font-family: system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,"Helvetica Neue",Arial,"Noto Sans",sans-serif; margin: 2rem; line-height: 1.5; }
h1 { font-size: 1.8rem; margin-bottom: 1rem; }
a { color: #0b5ed7; text-decoration: none; }
a:hover { text-decoration: underline; }
nav p { margin-bottom: 1.25rem; }
table.calc { border-collapse: collapse; margin-top: 1rem; }
.calc th { background: #f0f0f0; text-align: left; }
.calc td, .calc th { border: 1px solid #ccc; padding: 0.5rem 0.75rem; }
@media (prefers-color-scheme: dark) {
  .calc th { background: #222; }
  .calc td, .calc th { border-color: #444; }
}