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

:root {
    --color-primary: #2c3e50;
    --color-accent: #3498db;
    --color-text: #333;
    --color-muted: #999;
    --color-bg: #f5f5f5;
}

body {
    font-family: "Microsoft YaHei", sans-serif;
    color: var(--color-text);
    background: var(--color-bg);
}

nav {
    background: var(--color-primary);
    color: white;
    padding: 20px 40px;
}

nav h1 {
    font-size: 24px;
}

main {
    max-width: 960px;
    margin: 30px auto;
    padding: 0 20px;
}

footer {
    text-align: center;
    padding: 20px;
    color: var(--color-muted);
}