:root { font-family: system-ui, sans-serif; line-height: 1.618; }
* { box-sizing: border-box; }
body { margin: 0; }
.container { max-width: 960px; margin: 0 auto; padding: 16px; }
header { border-bottom: 1px solid #ddd; }
nav a { margin-right: 12px; text-decoration: none; }
@media (max-width : 600px ){ nav a { display: inline-block; margin: 8px 8px 0 0; } }