* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft YaHei", sans-serif;
}
/* 核心修复：禁止页面横向溢出 */
html, body {
    overflow-x: hidden;
    max-width: 100vw;
}
:root {
    --main-blue: #165DFF;
    --dark-blue: #0E42B3;
    --light-blue: #E8F3FF;
    --text-dark: #222;
    --text-gray: #555;
    --white: #fff;
    --red: #E63946;
}
body {
    color: var(--text-dark);
    background: #F9FAFB;
    line-height: 1.6;
    font-size: 15px;
}
img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 12px;
}
.section { padding: 25px 0; }
.section-title {
    text-align: center;
    margin-bottom: 30px;
    color: var(--main-blue);
    font-size: 26px;
    font-weight: bold;
}
.section-title::after {
    content: "";
    width: 70px;
    height: 3px;
    background: var(--main-blue);
    display: block;
    margin: 8px auto 0;
    border-radius: 3px;
}

/* 导航 */
.header-nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    z-index: 999;
    height: 65px;
    display: flex;
    align-items: center;
}
.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    font-size: 20px;
    font-weight: bold;
    color: var(--main-blue);
    display: flex;
    align-items: center;
    gap: 6px;
}
.nav-menu {
    display: flex;
    gap: 20px;
}
.nav-menu li a {
    display: flex;
    align-items: center;
    gap: 5px;
    font-size: 14px;
    font-weight: 500;
    transition: 0.3s;
}
.nav-menu li a:hover {
    color: var(--main-blue);
    transform: translateY(-1px);
}

/* Banner */
.banner {
    background: linear-gradient(rgba(22, 93, 255, 0.85), rgba(14, 66, 179, 0.85)), url('../zhuangji/banner.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: #fff;
    padding: 120px 0 65px 0;
    text-align: center;
}
.banner h1 {
    font-size: 32px;
    margin-bottom: 12px;
    line-height: 1.3;
}
.banner p {
    font-size: 17px;
    opacity: 0.95;
    margin-bottom: 20px;
    line-height: 1.5;
}
.banner-btn {
    display: inline-block;
    padding: 12px 30px;
    background: #fff;
    color: var(--main-blue);
    border-radius: 50px;
    font-weight: bold;
    font-size: 15px;
    transition: 0.3s;
}
.banner-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.12);
}

/* 装机展示图 */
.install-img {
    margin: 20px auto;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

/* 服务卡片 */
.card-group {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
}
.card {
    background: #fff;
    padding: 25px 18px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 3px 10px rgba(0,0,0,0.04);
    border-top: 3px solid var(--main-blue);
    transition: 0.3s;
}
.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 6px 16px rgba(0,0,0,0.08);
}
.card i {
    font-size: 34px;
    color: var(--main-blue);
    margin-bottom: 12px;
}
.card h3 {
    margin-bottom: 8px;
    font-size: 17px;
    font-weight: bold;
}
.card p {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.6;
}
.card img {
    margin-bottom: 12px;
}

/* 报价表格 */
.table-box {
    background: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0,0,0,0.04);
}
table { width: 100%; border-collapse: collapse; }
th { background: var(--main-blue); color: #fff; padding: 14px; font-size:16px; font-weight:bold; }
td { padding: 12px; text-align: center; border-bottom: 1px solid #eee; font-size:15px; }
tr:nth-child(even) { background: var(--light-blue); }

/* 联系 */
.contact-box {
    background: var(--light-blue);
    padding: 35px;
    border-radius: 10px;
    text-align: center;
}
.contact-info {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
    align-items: center;
    text-align: left;
}
.contact-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
}
.contact-item i { color: var(--main-blue); font-size: 20px; }

/* 移动端底部导航 */
.mobile-footer-nav {
    display: none;
    position: fixed;
    bottom: 0;
    width: 100%;
    background: #fff;
    box-shadow: 0 -2px 8px rgba(0,0,0,0.08);
    height: 55px;
    z-index: 998;
}
.mobile-nav-list {
    display: flex;
    justify-content: space-around;
    align-items: center;
    height: 100%;
}
.mobile-nav-item {
    text-align: center;
    font-size: 12px;
}
.mobile-nav-item i {
    display: block;
    font-size: 18px;
    color: var(--main-blue);
    margin-bottom: 3px;
}

/* 返回顶部 */
.back-top {
    position: fixed;
    right: 15px;
    bottom: 70px;
    width: 42px;
    height: 42px;
    background: var(--main-blue);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: 0.3s;
}
.back-top.show {
    opacity: 1;
    visibility: visible;
}

/* 自适应 */
@media (max-width: 768px) {
    .header-nav { height: auto; padding: 8px 0; }
    .nav-wrapper { flex-direction: column; gap: 8px; }
    .nav-menu { width: 100%; overflow-x: auto; white-space: nowrap; padding-bottom: 5px; gap: 12px; }
    
    .card-group { grid-template-columns: repeat(2, 1fr); gap:12px; }
    
    .mobile-footer-nav { display: block; }
    .body-padding { padding-top: 100px; }
    .body-padding-bottom { padding-bottom: 65px; }

    .banner {
        padding: 60px 15px 50px 15px;
        width: 100%;
    }
    .banner h1 {
        font-size: 20px;
        line-height: 1.35;
        max-width: 100%;
        white-space: normal;
    }
    .banner p {
        font-size: 15px;
        line-height: 1.4;
        margin-top: 8px;
        white-space: normal;
    }
}