body{
    margin:0;
    font-family:"Microsoft YaHei",sans-serif;
    background:#f5f7fa;
    color:#333;
}

/* 导航栏 */

nav{
    position:fixed;
    top:0;
    left:0;
    width:100%;
    box-sizing:border-box;

    display:flex;
    justify-content:space-between;
    align-items:center;

    padding:18px 60px;

    background:#ffffff;
    box-shadow:0 2px 10px rgba(0,0,0,.05);

    z-index:999;
}

nav ul{
    display:flex;
    gap:30px;
    list-style:none;
    margin:0;
    padding:0;
}

nav a{
    text-decoration:none;
    color:#333;
    font-weight:500;
}

nav a:hover{
    color:#0F62FE;
}

/* 首屏 */

header{
    background:linear-gradient(135deg,#0F62FE,#1E88E5);

    color:white;

    text-align:center;

    padding:120px 20px 60px;

    min-height:auto;
}

header h1{
    font-size:48px;
    margin-bottom:40px;
}

header p{
    font-size:48px;
    max-width:900px;
    margin:auto;
}

/* 数据区 */

.stats{
    display:flex;
    gap:80px;
    margin-top:50px;
}

.stats h2{
    font-size:56px;
    margin-bottom:8px;
}

.stats p{
    font-size:18px;
    margin-top:10px;
}

/* 通用区块 */

section{
    max-width:1200px;
    margin:auto;
    padding:80px 20px;
}

section h2{
    font-size:48px;
    margin-bottom:40px;
}

/* 卡片 */

.cards{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(260px,1fr));
    gap:24px;
}

.card{
    background:white;

    border-radius:18px;

    padding:30px;

    box-shadow:0 8px 30px rgba(0,0,0,.06);

    transition:.3s;
}

.card:hover{
    transform:translateY(-6px);
}

.card h3{
    margin-top:0;
}

/* 联系我们 */

#contact .card{
    text-align:left;
}

/* 按钮 */

.btn{
    display:inline-block;

    margin-top:40px;

    background:white;

    color:#0F62FE;

    padding:14px 32px;

    border-radius:12px;

    font-weight:600;
}

/* 页脚 */

footer{
    background:#111827;
    color:white;
    text-align:center;
    padding:30px;
    margin-top:60px;
}
.hero{
    max-width:1200px;
    margin:auto;
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:60px;
}

.hero-left{
    flex:1;
}

.hero-right{
    flex:1;
    display:flex;
    justify-content:center;
}

header{
    background:
    linear-gradient(
    135deg,
    #0F62FE,
    #1E88E5
    );
    padding:70px 30px 50px;
}

.hero h1{
    font-size:56px;
    line-height:1.2;
    margin-bottom:20px;
}

.subtitle{
    max-width:520px;
    font-size:22px;
    line-height:1.8;
    color:rgba(255,255,255,.92);
}

.hero-buttons{
    margin-top:40px;
    display:flex;
    gap:20px;
}

.btn-primary{
    background:white;
    color:#0F62FE;
    padding:14px 30px;
    border-radius:10px;
    text-decoration:none;
    font-weight:600;
}

.btn-secondary{
    border:2px solid rgba(255,255,255,.8);
    color:white;
    padding:14px 32px;
    border-radius:12px;
}

.btn-primary:hover,
.btn-secondary:hover{
    transform:translateY(-3px);
}

.drone-placeholder{

    width:420px;
    height:420px;

    border-radius:50%;

    background:rgba(255,255,255,.12);

    display:flex;
    align-items:center;
    justify-content:center;

    font-size:100px;

     box-shadow:
     0 0 80px rgba(255,255,255,.15);
}