:root {
    --bg-color: #ffffff;
    --text-color: #333333;
    --link-color: #0056b3;
    --font-stack: system-ui, -apple-system, sans-serif;
}
@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #121212;
        --text-color: #e0e0e0;
        --link-color: #66b0ff;
    }
}
body {
    font-family: var(--font-stack);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    margin: 0 auto;
    max-width: 800px;
    padding: 1rem;
}
header, footer {
    padding: 1rem 0;
    border-bottom: 1px solid #ccc;
}
footer {
    border-bottom: none;
    border-top: 1px solid #ccc;
    margin-top: 2rem;
    font-size: 0.9rem;
}
a { color: var(--link-color); }
button, input {
    padding: 0.8rem;
    font-size: 1rem;
    margin: 0.5rem 0;
    min-height: 44px;
}
main { margin: 2rem 0; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }