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

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #f9fafb;
    color: #111827;
    line-height: 1.5;
}

a { color: #2563eb; }