/* =========================================================
   浙江七开电气有限公司 官网样式表
   配色方案：商务深蓝
   主色 #003399 / 辅色 #3366CC / 点缀 #FFCC00
   白 #FFFFFF / 浅灰 #CCCCCC / 黑 #000000
   ========================================================= */

/* ---------- 重置与基础 ---------- */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --c-main:#003399;      /* 主色 深蓝 */
  --c-sub:#3366CC;       /* 辅色 亮蓝 */
  --c-accent:#FFCC00;    /* 点缀 金黄 */
  --c-white:#FFFFFF;
  --c-gray:#CCCCCC;
  --c-black:#000000;
  --c-dark:#001a4d;
  --c-text:#222222;
  --c-text-light:#666666;
  --c-bg:#f5f7fb;
  --radius:8px;
  --shadow:0 4px 20px rgba(0,0,0,.10);
  --shadow-hover:0 8px 30px rgba(0,51,153,.18);
  --container:1200px;
}
html{font-size:16px;scroll-behavior:smooth}
body{
  font-family:"Microsoft YaHei","PingFang SC","Helvetica Neue",Arial,sans-serif;
  color:var(--c-text);
  line-height:1.7;
  background:var(--c-white);
  overflow-x:hidden;
}
img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none;transition:color .2s}
a:hover{color:var(--c-sub)}
ul,ol{list-style:none}
h1,h2,h3,h4,h5,h6{font-weight:700;line-height:1.4}

/* ---------- 通用容器 ---------- */
.container{max-width:var(--container);margin:0 auto;padding:0 20px}
.section{padding:60px 0}
.section-bg{background:var(--c-bg)}

/* ---------- 通用标题 ---------- */
.sec-title{text-align:center;margin-bottom:45px}
.sec-title h2{
  font-size:30px;color:var(--c-main);position:relative;display:inline-block;padding-bottom:14px
}
.sec-title h2::after{
  content:"";position:absolute;bottom:0;left:50%;transform:translateX(-50%);
  width:60px;height:4px;background:var(--c-accent);border-radius:2px
}
.sec-title p{margin-top:14px;color:var(--c-text-light);font-size:15px}

/* ---------- 顶部条 ---------- */
.topbar{
  background:var(--c-dark);color:#cdd6ee;font-size:13px;padding:7px 0
}
.topbar .container{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px}
.topbar a{color:#cdd6ee}
.topbar a:hover{color:var(--c-accent)}
.topbar .topbar-left span{margin-right:22px}
.topbar .topbar-left i{color:var(--c-accent);margin-right:5px}

/* ---------- 导航头部 ---------- */
.header{
  background:var(--c-white);position:sticky;top:0;z-index:1000;
  box-shadow:0 2px 10px rgba(0,0,0,.06)
}
.header .container{display:flex;align-items:center;justify-content:space-between;height:76px}
.logo{display:flex;align-items:center;gap:12px}
.logo .logo-icon{
  width:46px;height:46px;background:var(--c-main);border-radius:8px;
  display:flex;align-items:center;justify-content:center;color:var(--c-accent);
  font-size:24px;font-weight:900;flex-shrink:0
}
.logo .logo-text{display:flex;flex-direction:column;line-height:1.2}
.logo .logo-text strong{font-size:19px;color:var(--c-main);letter-spacing:1px}
.logo .logo-text small{font-size:11px;color:var(--c-text-light);letter-spacing:1px}

.nav{display:flex;align-items:center;gap:4px}
.nav a{
  display:block;padding:10px 16px;font-size:16px;color:var(--c-text);
  border-radius:var(--radius);position:relative
}
.nav a:hover,.nav a.active{color:var(--c-main)}
.nav a.active::after{
  content:"";position:absolute;bottom:2px;left:16px;right:16px;height:3px;
  background:var(--c-accent);border-radius:2px
}
.nav-toggle{
  display:none;background:none;border:none;font-size:26px;color:var(--c-main);
  cursor:pointer;padding:6px
}

/* ---------- 轮播横幅 ---------- */
.banner{
  position:relative;height:480px;overflow:hidden;background:var(--c-dark)
}
.banner .slide{
  position:absolute;inset:0;opacity:0;transition:opacity 1s ease;
  display:flex;align-items:center;justify-content:center
}
.banner .slide.active{opacity:1}
.banner .slide img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.banner .slide::after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,rgba(0,26,77,.82) 0%,rgba(0,26,77,.45) 60%,rgba(0,26,77,.2) 100%)}
.banner .slide-content{position:relative;z-index:2;color:var(--c-white);max-width:640px;padding:0 20px}
.banner .slide-content h1{font-size:42px;margin-bottom:18px;line-height:1.3}
.banner .slide-content p{font-size:17px;margin-bottom:28px;opacity:.92}
.banner-dots{position:absolute;bottom:24px;left:50%;transform:translateX(-50%);z-index:3;display:flex;gap:10px}
.banner-dots button{
  width:12px;height:12px;border-radius:50%;border:none;background:rgba(255,255,255,.5);
  cursor:pointer;transition:all .3s
}
.banner-dots button.active{background:var(--c-accent);width:32px;border-radius:6px}
.btn{
  display:inline-block;padding:12px 32px;border-radius:var(--radius);
  font-size:15px;font-weight:600;transition:all .3s;cursor:pointer;border:none
}
.btn-primary{background:var(--c-accent);color:var(--c-black)}
.btn-primary:hover{background:#ffd633;transform:translateY(-2px);box-shadow:0 6px 20px rgba(255,204,0,.4)}
.btn-outline{background:transparent;color:var(--c-white);border:2px solid var(--c-white)}
.btn-outline:hover{background:var(--c-white);color:var(--c-main)}

/* ---------- 页面内页头(列表/详情) ---------- */
.page-header{
  position:relative;height:240px;display:flex;align-items:center;justify-content:center;
  background:var(--c-dark);overflow:hidden
}
.page-header img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:.35}
.page-header::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(0,26,77,.6),rgba(0,26,77,.85))}
.page-header h1{position:relative;z-index:2;color:var(--c-white);font-size:34px}
.breadcrumb{
  position:relative;z-index:2;color:#cdd6ee;font-size:14px;text-align:center;margin-top:10px
}
.breadcrumb a{color:#cdd6ee}
.breadcrumb a:hover{color:var(--c-accent)}

/* ---------- 首页-关于简介 ---------- */
.about-brief{display:flex;gap:40px;align-items:center;flex-wrap:wrap}
.about-brief .about-img{flex:1;min-width:300px;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}
.about-brief .about-img img{width:100%;height:320px;object-fit:cover}
.about-brief .about-text{flex:1.2;min-width:300px}
.about-brief .about-text h2{font-size:26px;color:var(--c-main);margin-bottom:16px}
.about-brief .about-text p{color:var(--c-text-light);margin-bottom:14px}
.about-brief .stats{display:flex;gap:30px;margin-top:24px;flex-wrap:wrap}
.about-brief .stats .stat-item{text-align:center}
.about-brief .stats .stat-num{font-size:32px;font-weight:800;color:var(--c-main)}
.about-brief .stats .stat-label{font-size:13px;color:var(--c-text-light)}

/* ---------- 首页-产品网格 ---------- */
.product-grid{
  display:grid;grid-template-columns:repeat(4,1fr);gap:24px
}
.product-card{
  background:var(--c-white);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:all .3s;border:1px solid #eef0f5
}
.product-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-hover);border-color:var(--c-sub)}
.product-card .card-img{height:200px;overflow:hidden;background:#f5f7fb}
.product-card .card-img img{width:100%;height:100%;object-fit:cover;transition:transform .4s}
.product-card:hover .card-img img{transform:scale(1.08)}
.product-card .card-body{padding:16px 18px}
.product-card .card-body h3{font-size:16px;color:var(--c-text);margin-bottom:8px;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.product-card .card-body p{font-size:13px;color:var(--c-text-light);height:42px;overflow:hidden}
.product-card .card-more{display:inline-block;margin-top:10px;font-size:13px;color:var(--c-sub);font-weight:600}

/* ---------- 首页-新闻列表 ---------- */
.news-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.news-card{
  background:var(--c-white);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:all .3s
}
.news-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover)}
.news-card .card-img{height:180px;overflow:hidden}
.news-card .card-img img{width:100%;height:100%;object-fit:cover;transition:transform .4s}
.news-card:hover .card-img img{transform:scale(1.06)}
.news-card .card-body{padding:18px 20px}
.news-card .card-date{font-size:13px;color:var(--c-sub);margin-bottom:8px}
.news-card .card-body h3{font-size:16px;margin-bottom:10px;line-height:1.5;
  display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.news-card .card-body p{font-size:13px;color:var(--c-text-light);height:42px;overflow:hidden}

/* ---------- 首页-优势 ---------- */
.advantage-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.advantage-item{
  text-align:center;padding:30px 20px;background:var(--c-white);border-radius:var(--radius);
  box-shadow:var(--shadow);transition:all .3s;border-top:4px solid transparent
}
.advantage-item:hover{border-top-color:var(--c-accent);transform:translateY(-6px)}
.advantage-item .adv-icon{
  width:64px;height:64px;margin:0 auto 18px;background:var(--c-main);color:var(--c-accent);
  border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:28px;font-weight:800
}
.advantage-item h3{font-size:18px;color:var(--c-main);margin-bottom:10px}
.advantage-item p{font-size:14px;color:var(--c-text-light)}

/* ---------- CTA 区块 ---------- */
.cta-section{
  background:linear-gradient(135deg,var(--c-main),var(--c-sub));
  color:var(--c-white);text-align:center;padding:50px 0
}
.cta-section h2{font-size:28px;margin-bottom:12px}
.cta-section p{font-size:16px;margin-bottom:24px;opacity:.9}
.cta-section .btn-primary{background:var(--c-accent)}

/* ---------- 列表页通用 ---------- */
.list-page{padding:50px 0}
.list-toolbar{display:flex;justify-content:space-between;align-items:center;margin-bottom:30px;flex-wrap:wrap;gap:12px}
.list-toolbar .result-count{color:var(--c-text-light);font-size:14px}
.list-toolbar .result-count strong{color:var(--c-main)}

.list-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.list-grid.product-list{grid-template-columns:repeat(4,1fr)}

/* 分页 */
.pagination{display:flex;justify-content:center;gap:8px;margin-top:40px;flex-wrap:wrap}
.pagination a{
  display:inline-flex;align-items:center;justify-content:center;min-width:38px;height:38px;
  padding:0 12px;border:1px solid var(--c-gray);border-radius:var(--radius);font-size:14px;color:var(--c-text)
}
.pagination a:hover,.pagination a.active{background:var(--c-main);color:var(--c-white);border-color:var(--c-main)}

/* ---------- 详情页 ---------- */
.detail-page{padding:40px 0}
.detail-layout{display:flex;gap:30px;align-items:flex-start}
.detail-main{flex:1;min-width:0}
.detail-side{width:300px;flex-shrink:0}
.detail-card{
  background:var(--c-white);border-radius:var(--radius);box-shadow:var(--shadow);
  overflow:hidden;margin-bottom:24px
}
.detail-card .detail-img{width:100%;max-height:420px;overflow:hidden}
.detail-card .detail-img img{width:100%;height:100%;object-fit:cover}
.detail-card .detail-info{padding:24px 28px}
.detail-card h1{font-size:26px;color:var(--c-main);margin-bottom:14px;line-height:1.4}
.detail-meta{display:flex;gap:20px;font-size:13px;color:var(--c-text-light);margin-bottom:20px;padding-bottom:16px;border-bottom:1px dashed var(--c-gray);flex-wrap:wrap}
.detail-meta span i{color:var(--c-sub);margin-right:4px}
.detail-content{font-size:15px;line-height:1.9}
.detail-content h2{font-size:20px;color:var(--c-main);margin:24px 0 12px;padding-left:12px;border-left:4px solid var(--c-accent)}
.detail-content h3{font-size:17px;color:var(--c-main);margin:18px 0 10px}
.detail-content p{margin-bottom:14px;color:#444}
.detail-content ul{margin:10px 0 14px 20px}
.detail-content ul li{list-style:disc;margin-bottom:6px;color:#444}
.detail-content table{width:100%;border-collapse:collapse;margin:16px 0}
.detail-content table th,.detail-content table td{border:1px solid var(--c-gray);padding:8px 12px;font-size:14px}
.detail-content table th{background:var(--c-main);color:var(--c-white)}
.detail-content img{border-radius:var(--radius);margin:14px 0}
.detail-nav{display:flex;justify-content:space-between;margin-top:24px;padding-top:20px;border-top:1px solid #eef0f5;flex-wrap:wrap;gap:12px}
.detail-nav a{font-size:14px;color:var(--c-sub)}
.detail-nav a:hover{color:var(--c-accent)}

/* 侧边栏 */
.side-block{background:var(--c-white);border-radius:var(--radius);box-shadow:var(--shadow);margin-bottom:24px;overflow:hidden}
.side-block .side-title{background:var(--c-main);color:var(--c-white);padding:14px 20px;font-size:16px}
.side-block .side-body{padding:16px 20px}
.side-list li{padding:10px 0;border-bottom:1px dashed #eef0f5}
.side-list li:last-child{border-bottom:none}
.side-list li a{font-size:14px;display:flex;justify-content:space-between;align-items:center;gap:8px}
.side-list li a:hover{color:var(--c-sub)}
.side-list li .side-date{font-size:12px;color:var(--c-text-light);flex-shrink:0}
.side-contact{background:var(--c-main);color:var(--c-white);padding:20px;border-radius:var(--radius)}
.side-contact h3{font-size:18px;margin-bottom:14px;color:var(--c-accent)}
.side-contact p{font-size:14px;margin-bottom:10px;opacity:.95}

/* ---------- 关于我们 ---------- */
.about-page{padding:50px 0}
.about-block{margin-bottom:40px}
.about-block h2{font-size:24px;color:var(--c-main);margin-bottom:16px;padding-left:14px;border-left:5px solid var(--c-accent)}
.about-block p{margin-bottom:14px;color:#444;font-size:15px;line-height:1.9}
.about-block img{border-radius:var(--radius);margin:16px 0;box-shadow:var(--shadow)}
.timeline{position:relative;padding-left:30px}
.timeline::before{content:"";position:absolute;left:8px;top:0;bottom:0;width:3px;background:var(--c-sub)}
.timeline-item{position:relative;margin-bottom:24px}
.timeline-item::before{content:"";position:absolute;left:-26px;top:6px;width:13px;height:13px;background:var(--c-accent);border:3px solid var(--c-main);border-radius:50%}
.timeline-item h4{color:var(--c-main);margin-bottom:4px}
.timeline-item p{font-size:14px;color:var(--c-text-light)}
.value-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.value-card{padding:24px;background:var(--c-bg);border-radius:var(--radius);text-align:center}
.value-card .vc-icon{font-size:36px;color:var(--c-main);margin-bottom:10px}
.value-card h3{color:var(--c-main);margin-bottom:8px}

/* ---------- 联系我们 ---------- */
.contact-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:40px}
.contact-form .form-group{margin-bottom:18px}
.contact-form label{display:block;margin-bottom:6px;font-size:14px;color:var(--c-text);font-weight:600}
.contact-form input,.contact-form textarea{
  width:100%;padding:10px 14px;border:1px solid var(--c-gray);border-radius:var(--radius);
  font-size:14px;font-family:inherit
}
.contact-form input:focus,.contact-form textarea:focus{outline:none;border-color:var(--c-sub)}
.contact-form textarea{min-height:120px;resize:vertical}
.contact-info-card{background:var(--c-main);color:var(--c-white);padding:30px;border-radius:var(--radius)}
.contact-info-card h2{color:var(--c-accent);margin-bottom:18px;font-size:22px}
.contact-info-card ul li{margin-bottom:14px;font-size:15px}
.contact-info-card ul li strong{display:inline-block;width:80px;color:var(--c-accent)}
.map-box{margin-top:30px;border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow)}

/* ---------- 页脚 ---------- */
.footer{background:var(--c-dark);color:#aab4cc;padding:50px 0 0}
.footer .container{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.2fr;gap:30px}
.footer h4{color:var(--c-white);margin-bottom:18px;font-size:16px}
.footer p,.footer li{font-size:14px;margin-bottom:10px;line-height:1.8}
.footer a{color:#aab4cc}
.footer a:hover{color:var(--c-accent)}
.footer .footer-logo{display:flex;align-items:center;gap:12px;margin-bottom:16px}
.footer .footer-logo .logo-icon{width:42px;height:42px}
.footer .footer-logo strong{color:var(--c-white);font-size:17px}
.footer .qr-box{display:flex;gap:16px;margin-top:10px}
.footer .qr-box .qr-item{text-align:center}
.footer .qr-box .qr-item .qr-placeholder{
  width:90px;height:90px;background:var(--c-white);border-radius:6px;margin-bottom:6px;
  display:flex;align-items:center;justify-content:center;color:var(--c-main);font-size:12px
}
.footer-bottom{
  margin-top:40px;padding:18px 0;border-top:1px solid rgba(255,255,255,.1);
  text-align:center;font-size:13px;color:#8893ad
}
.footer-bottom a{color:#8893ad}
.footer-bottom a:hover{color:var(--c-accent)}
.footer-bottom .icp{margin:0 8px}

/* ---------- 返回顶部 ---------- */
.back-top{
  position:fixed;right:24px;bottom:24px;width:46px;height:46px;background:var(--c-main);
  color:var(--c-white);border:none;border-radius:50%;font-size:22px;cursor:pointer;
  z-index:999;opacity:0;visibility:hidden;transition:all .3s;box-shadow:var(--shadow)
}
.back-top.show{opacity:1;visibility:visible}
.back-top:hover{background:var(--c-sub)}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width:1024px){
  .product-grid{grid-template-columns:repeat(3,1fr)}
  .list-grid.product-list{grid-template-columns:repeat(3,1fr)}
  .footer .container{grid-template-columns:1fr 1fr}
}
@media (max-width:768px){
  .topbar .topbar-left span{margin-right:12px;display:inline-block}
  .nav{
    position:fixed;top:76px;left:0;right:0;background:var(--c-white);
    flex-direction:column;align-items:stretch;padding:10px 0;
    box-shadow:0 6px 20px rgba(0,0,0,.12);gap:0;
    max-height:0;overflow:hidden;transition:max-height .35s ease
  }
  .nav.open{max-height:500px}
  .nav a{padding:14px 24px;border-bottom:1px solid #f0f2f7}
  .nav-toggle{display:block}
  .banner{height:360px}
  .banner .slide-content h1{font-size:26px}
  .banner .slide-content p{font-size:14px}
  .product-grid,.list-grid,.list-grid.product-list{grid-template-columns:repeat(2,1fr)}
  .advantage-grid{grid-template-columns:repeat(2,1fr)}
  .news-grid{grid-template-columns:1fr}
  .sec-title h2{font-size:24px}
  .about-brief{flex-direction:column}
  .detail-layout{flex-direction:column}
  .detail-side{width:100%;display:grid;grid-template-columns:1fr 1fr;gap:20px}
  .contact-grid{grid-template-columns:1fr}
  .value-grid{grid-template-columns:1fr}
  .footer .container{grid-template-columns:1fr}
  .section{padding:40px 0}
  .page-header{height:180px}
  .page-header h1{font-size:26px}
}
@media (max-width:480px){
  .product-grid,.list-grid,.list-grid.product-list{grid-template-columns:1fr}
  .advantage-grid{grid-template-columns:1fr}
  .detail-side{grid-template-columns:1fr}
  .banner .slide-content h1{font-size:22px}
  .banner{height:300px}
}