/* 重置默认样式 */
*{margin:0;padding:0;box-sizing:border-box;}
 
body{
    font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif;
    background:#f7f7f7;
    color:#333;
    height:100vh;
    display:flex;
    align-items:center;
    justify-content:center;
}
 
.wrapper{
    text-align:center;
}
 
.logo{
    width:120px;      /* 按需调整 */
    margin-bottom:40px;
}
 
nav a{
    display:inline-block;
    margin:0 15px;
    padding:8px 16px;
    color:#555;
    text-decoration:none;
    font-size:16px;
    border-bottom:2px solid transparent;
    transition:.25s;
}
 
nav a:hover{
    color:#000;
    border-bottom-color:#000;
}