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


body{

    font-family:
    system-ui,
    -apple-system,
    "Segoe UI",
    sans-serif;

    background:
    #0f172a;

    color:#fff;

    min-height:100vh;

}


/* 整体布局 */

.layout{

    display:flex;

    min-height:100vh;

}



/* 左侧菜单 */

.sidebar{

    width:230px;

    background:
    #111827;

    padding:25px;

}



.logo{

    font-size:22px;

    font-weight:bold;

    margin-bottom:40px;

}



nav a{

    display:block;

    color:#cbd5e1;

    text-decoration:none;

    padding:14px 12px;

    border-radius:8px;

    margin-bottom:8px;

}



nav a:hover{

    background:#1e293b;

    color:white;

}



/* 右侧 */

.main{

    flex:1;

    padding:30px;

}



/* 顶部 */

header{

    display:flex;

    justify-content:space-between;

    align-items:center;

    margin-bottom:35px;

    font-size:18px;

}



header button{

    background:#ef4444;

    color:white;

    border:0;

    padding:10px 18px;

    border-radius:8px;

    cursor:pointer;

}



header button:hover{

    background:#dc2626;

}



/* 欢迎区域 */


.welcome{

    background:

    rgba(255,255,255,.06);

    padding:35px;

    border-radius:18px;

}



.welcome h1{

    margin-bottom:15px;

}



#username{

    color:#38bdf8;

}



.welcome p{

    color:#cbd5e1;

}



/* 卡片 */

.cards{

    margin-top:35px;

    display:grid;

    grid-template-columns:
    repeat(auto-fit,minmax(220px,1fr));

    gap:20px;

}



.card{

    background:

    rgba(255,255,255,.08);

    padding:25px;

    border-radius:15px;

}



.card h3{

    margin-bottom:15px;

}



/* 手机 */

@media(max-width:700px){


.layout{

    flex-direction:column;

}


.sidebar{

    width:100%;

}



.main{

    padding:20px;

}


}