/* 重置一些默认的样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
 
body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    color: #333;
    line-height: 1.6;
}
 
header {
    background-color: #333;
    color: #fff;
    padding: 10px 0;
    text-align: center;
}
 
nav ul {
    list-style: none;
    padding: 0;
}
 
nav ul li {
    display: inline;
    margin: 0 15px;
}
 
nav ul li a {
    color: #fff;
    text-decoration: none;
}
 
section {
    padding: 20px;
    margin: 20px;
    background-color: #fff;
    border-radius: 8px;
}
 
h2 {
    color: #333;
}
 
footer {
    text-align: center;
    padding: 10px 0;
    background-color: #333;
    color: #fff;
}