:root {
    --primary: #1e5eff;
    --primary-dark: #0f3fb3;
    --text: #1f2937;
    --text-light: #6b7280;
    --bg: #f6f8fb;
    --border: #e5e7eb;
    --radius: 10px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    color: var(--text);
    background: #fff;
    line-height: 1.7;
    font-size: 15px;
}
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; display: block; }
.container { max-width: 1180px; margin: 0 auto; padding: 0 20px; }

/* 头部 */
.site-header {
    position: sticky; top: 0; z-index: 100;
    background: #fff; border-bottom: 1px solid var(--border);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.site-logo img { height: 40px; }
.site-nav ul { display: flex; list-style: none; gap: 6px; }
.site-nav a {
    display: block; padding: 8px 16px; color: var(--text);
    font-size: 15px; border-radius: 6px;
}
.site-nav a:hover { color: var(--primary); }
.site-nav a.active { color: var(--primary); font-weight: 600; }
.header-phone { font-size: 17px; font-weight: 700; color: var(--primary); white-space: nowrap; }
.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 5px 0; }

/* 首页轮播 */
.hero { position: relative; overflow: hidden; background: #0b1f4d; }
.hero-slide { display: none; }
.hero-slide.active { display: block; }
.hero-slide img { width: 100%; height: 420px; object-fit: cover; opacity: .9; }
.hero-text {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    text-align: center; color: #fff; width: 90%;
}
.hero-text h2 { font-size: 36px; margin-bottom: 12px; text-shadow: 0 2px 8px rgba(0,0,0,.4); }
.hero-text p { font-size: 17px; opacity: .92; text-shadow: 0 1px 4px rgba(0,0,0,.4); }
.hero-dots { position: absolute; bottom: 18px; left: 50%; transform: translateX(-50%); display: flex; gap: 8px; }
.hero-dots button { width: 10px; height: 10px; border-radius: 50%; border: 0; background: rgba(255,255,255,.45); cursor: pointer; }
.hero-dots button.active { background: #fff; }

/* 通用区块 */
.section { padding: 64px 0; }
.section.gray { background: var(--bg); }
.section-title { text-align: center; margin-bottom: 44px; }
.section-title h2 { font-size: 28px; }
.section-title p { color: var(--text-light); margin-top: 6px; font-size: 14px; }

/* 服务卡片 */
.service-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.service-card {
    background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
    padding: 32px 22px; text-align: center; transition: box-shadow .2s, transform .2s;
}
.service-card:hover { box-shadow: 0 8px 24px rgba(30,94,255,.1); transform: translateY(-4px); }
.service-card img { width: 52px; height: 52px; margin: 0 auto 16px; }
.service-card h3 { font-size: 17px; margin-bottom: 10px; }
.service-card p { color: var(--text-light); font-size: 13px; }

/* 案例 */
.case-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.case-item {
    background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
    overflow: hidden; transition: box-shadow .2s;
}
.case-item:hover { box-shadow: 0 8px 24px rgba(0,0,0,.08); }
.case-item .pic { height: 200px; overflow: hidden; background: var(--bg); }
.case-item .pic img { width: 100%; height: 100%; object-fit: cover; transition: transform .3s; }
.case-item:hover .pic img { transform: scale(1.04); }
.case-item .info { padding: 18px 20px; }
.case-item .cat { display: inline-block; font-size: 12px; color: var(--primary); background: #eef3ff; padding: 2px 10px; border-radius: 20px; margin-bottom: 8px; }
.case-item h3 { font-size: 16px; }
.case-item p { color: var(--text-light); font-size: 13px; margin-top: 6px; }

/* 新闻 */
.news-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.news-item { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; transition: box-shadow .2s; }
.news-item:hover { box-shadow: 0 8px 24px rgba(0,0,0,.06); }
.news-item time { font-size: 12px; color: var(--text-light); }
.news-item h3 { font-size: 16px; margin: 8px 0; }
.news-item h3 a { color: var(--text); }
.news-item h3 a:hover { color: var(--primary); }
.news-item p { color: var(--text-light); font-size: 13px; }

/* 关于 */
.about-wrap { display: grid; grid-template-columns: 1.2fr 1fr; gap: 48px; align-items: center; }
.about-wrap h2 { font-size: 26px; margin-bottom: 18px; }
.about-wrap .content p { margin-bottom: 12px; color: #374151; }
.contact-info-list { margin-top: 20px; list-style: none; }
.contact-info-list li { padding: 8px 0; border-bottom: 1px dashed var(--border); font-size: 14px; }
.contact-info-list b { display: inline-block; width: 80px; color: var(--text-light); font-weight: 400; }

/* 页头横幅（内页） */
.page-banner { background: linear-gradient(135deg, #123a9e, #1e5eff); color: #fff; padding: 64px 0; text-align: center; }
.page-banner h1 { font-size: 30px; }
.page-banner p { opacity: .85; margin-top: 8px; font-size: 14px; }

/* 文章/详情 */
.detail-body { max-width: 820px; margin: 0 auto; }
.detail-body h1 { font-size: 26px; margin-bottom: 10px; }
.detail-meta { color: var(--text-light); font-size: 13px; margin-bottom: 28px; }
.detail-content p { margin-bottom: 14px; }
.back-link { display: inline-block; margin-top: 32px; font-size: 14px; }

/* 联系 */
.contact-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 13px; color: var(--text-light); margin-bottom: 6px; }
.form-group input, .form-group textarea {
    width: 100%; padding: 11px 14px; border: 1px solid var(--border);
    border-radius: 8px; font-size: 14px; font-family: inherit;
}
.form-group textarea { min-height: 130px; resize: vertical; }
.btn {
    display: inline-block; background: var(--primary); color: #fff; border: 0;
    padding: 12px 36px; border-radius: 8px; font-size: 15px; cursor: pointer;
}
.btn:hover { background: var(--primary-dark); color: #fff; }
.alert { padding: 12px 16px; border-radius: 8px; margin-bottom: 20px; font-size: 14px; }
.alert.ok { background: #f0fdf4; color: #15803d; border: 1px solid #bbf7d0; }
.alert.err { background: #fef2f2; color: #b91c1c; border: 1px solid #fecaca; }

/* 页脚 */
.site-footer { background: #101828; color: #cbd5e1; padding: 48px 0 0; margin-top: 0; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 32px; padding-bottom: 36px; }
.site-footer h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 8px; }
.site-footer a { color: #cbd5e1; font-size: 13px; }
.site-footer a:hover { color: #fff; }
.footer-desc { font-size: 13px; color: #94a3b8; line-height: 1.8; }
.footer-copy { border-top: 1px solid #1f2937; padding: 18px 0; text-align: center; font-size: 13px; color: #94a3b8; }
.footer-copy a { color: #94a3b8; }

/* 分页 */
.pagination { text-align: center; margin-top: 36px; }
.pagination a, .pagination span {
    display: inline-block; padding: 7px 14px; border: 1px solid var(--border);
    border-radius: 6px; margin: 0 3px; font-size: 13px; color: var(--text);
}
.pagination .current { background: var(--primary); color: #fff; border-color: var(--primary); }

/* 响应式 */
@media (max-width: 900px) {
    .service-grid, .case-grid, .news-list { grid-template-columns: repeat(2, 1fr); }
    .about-wrap, .contact-wrap { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .hero-text h2 { font-size: 26px; }
    .hero-slide img { height: 280px; }
}
@media (max-width: 640px) {
    .service-grid, .case-grid, .news-list { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .header-phone { display: none; }
    .nav-toggle { display: block; }
    .site-nav {
        display: none; position: absolute; top: 68px; left: 0; right: 0;
        background: #fff; border-bottom: 1px solid var(--border); padding: 10px 16px;
    }
    .site-nav.open { display: block; }
    .site-nav ul { flex-direction: column; gap: 0; }
    .section { padding: 44px 0; }
}