/* ============================================================
   华信科技 企业官网 全局样式（响应式自适应）
   基于 ThinkPHP3 项目 Public 目录
   ============================================================ */

:root{
  --c-primary:#1e5eff;
  --c-primary-2:#3b7bff;
  --c-primary-dark:#1748d6;
  --c-dark:#0d1b3e;
  --c-dark-2:#13264f;
  --c-bg:#f4f6fb;
  --c-line:#e4e9f2;
  --c-text:#2b3550;
  --c-muted:#6b7690;
  --c-accent:#ff9f1c;
  --c-white:#ffffff;
  --radius:14px;
  --shadow:0 8px 28px rgba(13,27,62,.08);
  --shadow-lg:0 18px 46px rgba(13,27,62,.14);
  --header-h:72px;
  --font:"PingFang SC","Microsoft YaHei","Helvetica Neue",Helvetica,Arial,"Segoe UI",sans-serif;
}

*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  font-family:var(--font);
  color:var(--c-text);
  background:var(--c-white);
  font-size:16px;
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block;}
a{text-decoration:none;color:inherit;transition:color .25s ease;}
ul,ol{list-style:none;}
button{font-family:inherit;cursor:pointer;border:none;background:none;}
input,textarea,select{font-family:inherit;font-size:inherit;}

.container{width:100%;max-width:1200px;margin:0 auto;padding:0 24px;}

/* ---------- 通用区块 ---------- */
.section{padding:88px 0;}
.section--gray{background:var(--c-bg);}
.section--dark{background:var(--c-dark);color:#fff;}
.section-head{text-align:center;max-width:720px;margin:0 auto 52px;}
.section-head .eyebrow{
  display:inline-block;font-size:14px;font-weight:600;color:var(--c-primary);
  letter-spacing:2px;margin-bottom:12px;
}
.section-head h2{font-size:34px;font-weight:700;color:var(--c-dark);line-height:1.3;}
.section--dark .section-head h2{color:#fff;}
.section-head p{color:var(--c-muted);margin-top:14px;font-size:16px;}
.section--dark .section-head p{color:#b9c4dd;}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 32px;border-radius:999px;font-size:15px;font-weight:600;
  transition:all .28s ease;white-space:nowrap;
}
.btn--primary{background:var(--c-primary);color:#fff;box-shadow:0 6px 18px rgba(30,94,255,.35);}
.btn--primary:hover{background:var(--c-primary-dark);transform:translateY(-2px);box-shadow:0 10px 24px rgba(30,94,255,.42);}
.btn--ghost{background:rgba(255,255,255,.12);color:#fff;border:1px solid rgba(255,255,255,.45);}
.btn--ghost:hover{background:rgba(255,255,255,.22);transform:translateY(-2px);}
.btn--outline{background:transparent;color:var(--c-primary);border:1.5px solid var(--c-primary);}
.btn--outline:hover{background:var(--c-primary);color:#fff;}

/* ---------- 顶部导航 ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  height:var(--header-h);
  transition:background .3s ease,box-shadow .3s ease;
  background:transparent;
}
.site-header.is-scrolled{
  background:rgba(255,255,255,.96);
  box-shadow:0 2px 18px rgba(13,27,62,.08);
  backdrop-filter:blur(8px);
}
.site-header .container{
  height:100%;display:flex;align-items:center;justify-content:space-between;
}
.logo{display:flex;align-items:center;gap:10px;font-size:22px;font-weight:800;color:#fff;letter-spacing:.5px;}
.logo .logo-mark{
  width:38px;height:38px;border-radius:10px;background:linear-gradient(135deg,var(--c-primary),#7aa5ff);
  display:flex;align-items:center;justify-content:center;color:#fff;font-size:19px;font-weight:900;
}
.logo .logo-img{height:38px;width:auto;border-radius:8px;object-fit:contain;}
.site-header.is-scrolled .logo{color:var(--c-dark);}

.nav{display:flex;align-items:center;gap:6px;}
.nav a{
  display:block;padding:10px 18px;border-radius:999px;
  color:rgba(255,255,255,.92);font-size:15px;font-weight:500;
}
.site-header.is-scrolled .nav a{color:var(--c-text);}
.nav a:hover,.nav a.active{color:#fff;background:var(--c-primary);}
.site-header.is-scrolled .nav a:hover,.site-header.is-scrolled .nav a.active{color:#fff;}
.nav .nav-cta{margin-left:10px;}

.nav-toggle{display:none;width:42px;height:42px;position:relative;z-index:1101;}
.nav-toggle span{
  position:absolute;left:9px;right:9px;height:2.5px;border-radius:2px;background:#fff;
  transition:all .3s ease;
}
.nav-toggle span:nth-child(1){top:13px;}
.nav-toggle span:nth-child(2){top:20px;}
.nav-toggle span:nth-child(3){top:27px;}
.site-header.is-scrolled .nav-toggle span{background:var(--c-dark);}
.nav-toggle.open span:nth-child(1){top:20px;transform:rotate(45deg);background:#fff;}
.nav-toggle.open span:nth-child(2){opacity:0;}
.nav-toggle.open span:nth-child(3){top:20px;transform:rotate(-45deg);background:#fff;}

/* ---------- Hero ---------- */
.hero{
  position:relative;min-height:100vh;display:flex;align-items:center;
  background:#0b1b3a url('../images/hero.jpg') center/cover no-repeat;
  color:#fff;padding:140px 0 90px;overflow:hidden;
}
.hero::before{
  content:"";position:absolute;inset:0;
  background:linear-gradient(100deg,rgba(10,22,52,.88) 0%,rgba(10,22,52,.55) 45%,rgba(10,22,52,.18) 100%);
}
.hero .container{position:relative;z-index:2;}
.hero-badge{
  display:inline-flex;align-items:center;gap:8px;padding:7px 16px;border-radius:999px;
  background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.28);
  font-size:13.5px;letter-spacing:1px;margin-bottom:22px;
}
.hero-badge::before{content:"";width:8px;height:8px;border-radius:50%;background:#4ade80;box-shadow:0 0 0 3px rgba(74,222,128,.25);}
.hero h1{font-size:52px;font-weight:800;line-height:1.22;max-width:640px;letter-spacing:.5px;}
.hero h1 .hl{color:#6ea3ff;}
.hero .sub{font-size:18px;color:rgba(255,255,255,.82);max-width:560px;margin:22px 0 34px;}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap;}
.hero-stats{
  display:flex;gap:0;margin-top:64px;max-width:640px;
  border-top:1px solid rgba(255,255,255,.2);padding-top:26px;
}
.hero-stats .hs{flex:1;}
.hero-stats .num{font-size:30px;font-weight:800;color:#fff;}
.hero-stats .num em{font-style:normal;color:#6ea3ff;}
.hero-stats .lab{font-size:13.5px;color:rgba(255,255,255,.68);margin-top:2px;}
.hero-scroll{
  position:absolute;left:50%;bottom:26px;transform:translateX(-50%);z-index:2;
  width:26px;height:42px;border:2px solid rgba(255,255,255,.5);border-radius:14px;
}
.hero-scroll::after{
  content:"";position:absolute;left:50%;top:7px;width:4px;height:8px;margin-left:-2px;
  border-radius:2px;background:#fff;animation:scrollDot 1.6s infinite;
}
@keyframes scrollDot{0%{opacity:1;transform:translateY(0);}100%{opacity:0;transform:translateY(12px);}}

/* ---------- 卡片网格 ---------- */
.grid{display:grid;gap:26px;}
.grid-3{grid-template-columns:repeat(3,1fr);}
.grid-4{grid-template-columns:repeat(4,1fr);}
.grid-2{grid-template-columns:repeat(2,1fr);}

/* 优势卡片 */
.feature-card{
  background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);
  padding:34px 28px;transition:transform .3s ease,box-shadow .3s ease;
}
.feature-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);}
.feature-card .ico{
  width:56px;height:56px;border-radius:14px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,#eaf1ff,#dce8ff);color:var(--c-primary);margin-bottom:20px;
}
.feature-card h3{font-size:19px;color:var(--c-dark);margin-bottom:10px;}
.feature-card p{font-size:14.5px;color:var(--c-muted);}

/* 业务卡片 */
.biz-card{
  position:relative;background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);
  padding:32px 28px;overflow:hidden;transition:transform .3s ease,box-shadow .3s ease;
}
.biz-card::after{
  content:"";position:absolute;left:0;top:0;bottom:0;width:4px;
  background:var(--c-primary);transform:scaleY(0);transform-origin:top;transition:transform .3s ease;
}
.biz-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);}
.biz-card:hover::after{transform:scaleY(1);}
.biz-card .ico{
  width:54px;height:54px;border-radius:12px;display:flex;align-items:center;justify-content:center;
  background:var(--c-bg);color:var(--c-primary);margin-bottom:18px;transition:all .3s ease;
}
.biz-card:hover .ico{background:var(--c-primary);color:#fff;}
.biz-card h3{font-size:18px;color:var(--c-dark);margin-bottom:8px;}
.biz-card p{font-size:14px;color:var(--c-muted);}
.biz-card .more{
  display:inline-flex;align-items:center;gap:4px;margin-top:16px;
  font-size:13.5px;font-weight:600;color:var(--c-primary);
}
.biz-card .more svg{transition:transform .25s ease;}
.biz-card:hover .more svg{transform:translateX(4px);}

/* ---------- 数据统计 ---------- */
.stats{
  position:relative;z-index:1;display:grid;grid-template-columns:repeat(4,1fr);gap:26px;
  background:linear-gradient(135deg,var(--c-dark),var(--c-dark-2));
  border-radius:22px;padding:54px 40px;
  box-shadow:var(--shadow-lg);
}
.stat{text-align:center;}
.stat .num{font-size:44px;font-weight:800;color:#fff;line-height:1.1;}
.stat .num em{font-style:normal;color:#6ea3ff;}
.stat .lab{color:#b9c4dd;font-size:15px;margin-top:8px;letter-spacing:1px;}

/* ---------- 案例卡片 ---------- */
.case-card{
  background:#fff;border-radius:var(--radius);overflow:hidden;border:1px solid var(--c-line);
  transition:transform .3s ease,box-shadow .3s ease;
}
.case-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);}
.case-card .thumb{position:relative;height:220px;overflow:hidden;}
.case-card .thumb img{width:100%;height:100%;object-fit:cover;transition:transform .5s ease;}
.case-card:hover .thumb img{transform:scale(1.06);}
.case-card .tag{
  position:absolute;left:16px;top:16px;padding:5px 14px;border-radius:999px;
  background:rgba(13,27,62,.72);color:#fff;font-size:12.5px;backdrop-filter:blur(4px);
}
.case-card .body{padding:24px 26px 26px;}
.case-card h3{font-size:18px;color:var(--c-dark);margin-bottom:8px;}
.case-card p{font-size:14px;color:var(--c-muted);}

/* ---------- 新闻 ---------- */
.news-grid{display:grid;grid-template-columns:1.1fr 1fr;gap:0;}
.news-feature{
  position:relative;border-radius:var(--radius);overflow:hidden;min-height:360px;display:flex;align-items:flex-end;
  color:#fff;margin-right:26px;
}
.news-feature img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;}
.news-feature::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(10,22,52,.05),rgba(10,22,52,.85));}
.news-feature .nf-body{position:relative;z-index:2;padding:28px;}
.news-feature .date{font-size:13px;color:#ffd591;margin-bottom:8px;}
.news-feature h3{font-size:21px;font-weight:700;line-height:1.4;}
.news-list{display:flex;flex-direction:column;}
.news-item{
  display:flex;justify-content:space-between;align-items:center;gap:18px;
  padding:20px 4px;border-bottom:1px solid var(--c-line);
}
.news-item:first-child{padding-top:4px;}
.news-item:last-child{border-bottom:none;}
.news-item h4{font-size:16px;color:var(--c-dark);transition:color .2s;}
.news-item:hover h4{color:var(--c-primary);}
.news-item .date{font-size:13.5px;color:var(--c-muted);white-space:nowrap;}

/* ---------- CTA ---------- */
.cta{
  position:relative;border-radius:22px;overflow:hidden;padding:72px 56px;text-align:center;color:#fff;
  background:linear-gradient(120deg,var(--c-primary),#0f2f7a 70%);
}
.cta::before{
  content:"";position:absolute;inset:0;
  background:radial-gradient(600px 240px at 85% 10%,rgba(255,255,255,.16),transparent 60%),
             radial-gradient(500px 220px at 10% 90%,rgba(110,163,255,.25),transparent 55%);
}
.cta h2{position:relative;font-size:32px;font-weight:800;margin-bottom:14px;}
.cta p{position:relative;color:rgba(255,255,255,.85);margin-bottom:30px;font-size:16.5px;}
.cta .btn{position:relative;}

/* ---------- 页脚 ---------- */
.site-footer{background:#0a1630;color:#aeb9d4;font-size:14.5px;}
.footer-top{display:grid;grid-template-columns:1.6fr 1fr 1fr 1.3fr;gap:40px;padding:70px 0 46px;}
.footer-brand .logo{color:#fff;margin-bottom:18px;}
.footer-brand p{color:#8b98b8;line-height:1.9;max-width:300px;}
.footer-col h4{color:#fff;font-size:16px;margin-bottom:20px;}
.footer-col li{margin-bottom:12px;}
.footer-col a:hover{color:#6ea3ff;}
.footer-contact li{display:flex;gap:10px;margin-bottom:14px;color:#c4cee6;}
.footer-contact svg{flex:none;margin-top:3px;color:#6ea3ff;}
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.1);padding:22px 0;
  display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;color:#7c88a8;font-size:13.5px;
}
.footer-bottom a{color:#7c88a8;}
.footer-bottom a:hover{color:#6ea3ff;}

/* ---------- 子页面横幅 ---------- */
.page-hero{
  position:relative;padding:150px 0 74px;color:#fff;text-align:center;
  background:#0b1b3a url('../images/hero.jpg') center 30%/cover no-repeat;
}
.page-hero::before{content:"";position:absolute;inset:0;background:rgba(10,22,52,.72);}
.page-hero .container{position:relative;z-index:2;}
.page-hero h1{font-size:38px;font-weight:800;margin-bottom:12px;}
.page-hero .crumb{font-size:14px;color:rgba(255,255,255,.72);}
.page-hero .crumb a:hover{color:#6ea3ff;}

/* ---------- 关于页 ---------- */
.about-intro{display:grid;grid-template-columns:1fr 1.15fr;gap:56px;align-items:center;}
.about-intro .media{position:relative;}
.about-intro .media img{border-radius:var(--radius);box-shadow:var(--shadow-lg);}
.about-intro .media .exp{
  position:absolute;right:-18px;bottom:-22px;background:var(--c-primary);color:#fff;
  border-radius:16px;padding:18px 24px;text-align:center;box-shadow:var(--shadow-lg);
}
.about-intro .media .exp b{display:block;font-size:30px;line-height:1.1;}
.about-intro .media .exp span{font-size:12.5px;opacity:.9;}
.about-intro h2{font-size:30px;color:var(--c-dark);margin-bottom:18px;line-height:1.35;}
.about-intro h2 em{font-style:normal;color:var(--c-primary);}
.about-intro p{color:var(--c-muted);margin-bottom:16px;}
.about-intro .points{margin-top:22px;display:grid;gap:12px;}
.about-intro .points li{display:flex;gap:10px;align-items:flex-start;font-size:15px;color:var(--c-text);}
.about-intro .points svg{flex:none;margin-top:3px;color:var(--c-primary);}

/* 时间轴 */
.timeline{position:relative;max-width:860px;margin:0 auto;}
.timeline::before{
  content:"";position:absolute;left:50%;top:0;bottom:0;width:2px;transform:translateX(-50%);
  background:linear-gradient(180deg,var(--c-primary),#c8d8ff);
}
.tl-item{position:relative;width:50%;padding:0 46px 44px;}
.tl-item:nth-child(odd){left:0;text-align:right;}
.tl-item:nth-child(even){left:50%;text-align:left;}
.tl-item .dot{
  position:absolute;top:4px;width:14px;height:14px;border-radius:50%;
  background:#fff;border:4px solid var(--c-primary);box-shadow:0 0 0 5px rgba(30,94,255,.15);
}
.tl-item:nth-child(odd) .dot{right:-7px;}
.tl-item:nth-child(even) .dot{left:-7px;}
.tl-item .year{font-size:15px;font-weight:800;color:var(--c-primary);letter-spacing:1px;margin-bottom:6px;}
.tl-item h4{font-size:17px;color:var(--c-dark);margin-bottom:6px;}
.tl-item p{font-size:14px;color:var(--c-muted);}

/* 文化卡片 */
.culture-card{
  background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);
  padding:34px 28px;text-align:center;transition:transform .3s ease,box-shadow .3s ease;
}
.culture-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);}
.culture-card .ico{
  width:58px;height:58px;margin:0 auto 18px;border-radius:50%;
  background:var(--c-bg);color:var(--c-primary);display:flex;align-items:center;justify-content:center;
}
.culture-card h3{font-size:18px;color:var(--c-dark);margin-bottom:10px;}
.culture-card p{font-size:14px;color:var(--c-muted);}

/* 荣誉 */
.honor-list{display:grid;grid-template-columns:repeat(4,1fr);gap:22px;}
.honor{
  background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);padding:26px 20px;text-align:center;
  transition:transform .3s ease,box-shadow .3s ease;
}
.honor:hover{transform:translateY(-5px);box-shadow:var(--shadow-lg);}
.honor .badge{font-size:32px;color:var(--c-accent);margin-bottom:10px;}
.honor h4{font-size:15.5px;color:var(--c-dark);margin-bottom:4px;}
.honor span{font-size:12.5px;color:var(--c-muted);}

/* ---------- 产品页 ---------- */
.product-block{margin-bottom:64px;}
.product-block:last-child{margin-bottom:0;}
.product-block .block-title{
  display:flex;align-items:center;gap:12px;font-size:24px;color:var(--c-dark);margin-bottom:28px;
}
.product-block .block-title::before{content:"";width:5px;height:24px;border-radius:3px;background:var(--c-primary);}
.prod-card{
  background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);overflow:hidden;
  transition:transform .3s ease,box-shadow .3s ease;
}
.prod-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);}
.prod-card .p-ico{
  height:150px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,#eef3ff,#e0eaff);color:var(--c-primary);
}
.prod-card .p-ico svg{width:52px;height:52px;}
.prod-card .p-body{padding:24px 26px 28px;}
.prod-card h3{font-size:18px;color:var(--c-dark);margin-bottom:8px;}
.prod-card p{font-size:14px;color:var(--c-muted);margin-bottom:14px;}
.prod-card ul{font-size:13.5px;color:var(--c-muted);}
.prod-card ul li{display:flex;gap:8px;margin-bottom:6px;}
.prod-card ul li::before{content:"";flex:none;width:6px;height:6px;border-radius:50%;background:var(--c-primary);margin-top:7px;}

/* ---------- 新闻列表页 ---------- */
.news-page-item{
  display:grid;grid-template-columns:220px 1fr;gap:26px;background:#fff;
  border:1px solid var(--c-line);border-radius:var(--radius);overflow:hidden;margin-bottom:24px;
  transition:transform .3s ease,box-shadow .3s ease;
}
.news-page-item:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);}
.news-page-item .n-thumb{height:100%;min-height:160px;}
.news-page-item .n-thumb img{width:100%;height:100%;object-fit:cover;}
.news-page-item .n-body{padding:24px 26px 22px 0;}
.news-page-item h3{font-size:19px;color:var(--c-dark);margin-bottom:8px;transition:color .2s;}
.news-page-item:hover h3{color:var(--c-primary);}
.news-page-item .n-date{font-size:13px;color:var(--c-muted);margin-bottom:10px;}
.news-page-item .n-date em{font-style:normal;color:var(--c-accent);margin-right:8px;}
.news-page-item p{font-size:14px;color:var(--c-muted);}

/* 新闻详情 */
.article{max-width:840px;margin:0 auto;background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);padding:48px 52px;}
.article h1{font-size:28px;color:var(--c-dark);line-height:1.4;margin-bottom:16px;}
.article .meta{display:flex;gap:20px;font-size:13.5px;color:var(--c-muted);padding-bottom:20px;border-bottom:1px solid var(--c-line);margin-bottom:26px;}
.article .content p{color:#3d4868;margin-bottom:18px;}
.article .content h2{font-size:21px;color:var(--c-dark);margin:26px 0 12px;}
.article .content img{border-radius:10px;margin:18px 0;}

/* ---------- 联系页 ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1.3fr;gap:40px;align-items:start;}
.contact-info{display:grid;gap:20px;}
.contact-card{
  display:flex;gap:16px;background:#fff;border:1px solid var(--c-line);
  border-radius:var(--radius);padding:22px 24px;
}
.contact-card .ico{
  width:48px;height:48px;flex:none;border-radius:12px;background:var(--c-bg);color:var(--c-primary);
  display:flex;align-items:center;justify-content:center;
}
.contact-card h4{font-size:15px;color:var(--c-dark);margin-bottom:4px;}
.contact-card p{font-size:14px;color:var(--c-muted);}
.contact-form{
  background:#fff;border:1px solid var(--c-line);border-radius:var(--radius);padding:36px 34px;
}
.contact-form h3{font-size:22px;color:var(--c-dark);margin-bottom:24px;}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:18px;}
.form-group{margin-bottom:18px;}
.form-group label{display:block;font-size:14px;font-weight:600;color:var(--c-dark);margin-bottom:8px;}
.form-group input,.form-group textarea,.form-group select{
  width:100%;padding:12px 15px;border:1.5px solid var(--c-line);border-radius:10px;
  font-size:15px;color:var(--c-text);background:#fbfcfe;transition:border-color .25s ease,box-shadow .25s ease;
}
.form-group input:focus,.form-group textarea:focus,.form-group select:focus{
  outline:none;border-color:var(--c-primary);box-shadow:0 0 0 4px rgba(30,94,255,.12);background:#fff;
}
.form-group textarea{min-height:130px;resize:vertical;}
.form-tip{font-size:12.5px;color:var(--c-muted);margin-top:6px;}
.form-msg{display:none;margin-top:16px;padding:13px 16px;border-radius:10px;font-size:14.5px;}
.form-msg.ok{display:block;background:#e8f8ef;color:#16794a;border:1px solid #bfe8d1;}
.form-msg.err{display:block;background:#fdecec;color:#b33737;border:1px solid #f5c6c6;}

/* 地图占位 */
.map-box{
  margin-top:64px;border-radius:var(--radius);overflow:hidden;border:1px solid var(--c-line);
  position:relative;height:320px;background:linear-gradient(135deg,#eaf1ff,#d8e6ff);
  display:flex;align-items:center;justify-content:center;color:var(--c-muted);
}

/* ---------- 回到顶部 ---------- */
.back-top{
  position:fixed;right:26px;bottom:26px;z-index:900;width:46px;height:46px;border-radius:50%;
  background:var(--c-primary);color:#fff;display:flex;align-items:center;justify-content:center;
  box-shadow:var(--shadow-lg);opacity:0;visibility:hidden;transform:translateY(12px);
  transition:all .3s ease;
}
.back-top.show{opacity:1;visibility:visible;transform:translateY(0);}
.back-top:hover{background:var(--c-primary-dark);}

/* ---------- 响应式 ---------- */
@media (max-width:1024px){
  .grid-4{grid-template-columns:repeat(2,1fr);}
  .grid-3{grid-template-columns:repeat(2,1fr);}
  .honor-list{grid-template-columns:repeat(2,1fr);}
  .footer-top{grid-template-columns:1fr 1fr;}
  .about-intro{grid-template-columns:1fr;gap:40px;}
  .about-intro .media{max-width:560px;}
  .news-grid{grid-template-columns:1fr;}
  .news-feature{margin-right:0;margin-bottom:24px;}
  .contact-grid{grid-template-columns:1fr;}
  .hero h1{font-size:42px;}
  .stats{grid-template-columns:repeat(2,1fr);padding:44px 26px;}
  .stat .num{font-size:34px;}
}

@media (max-width:768px){
  .section{padding:64px 0;}
  .container{padding:0 18px;}

  .nav{
    position:fixed;top:0;right:0;bottom:0;width:78%;max-width:330px;z-index:1100;
    background:var(--c-dark);flex-direction:column;align-items:flex-start;gap:4px;
    padding:92px 28px 40px;transform:translateX(100%);transition:transform .35s ease;
    box-shadow:-10px 0 40px rgba(0,0,0,.25);
  }
  .nav.open{transform:translateX(0);}
  .nav a{width:100%;padding:13px 16px;color:rgba(255,255,255,.9);font-size:16px;}
  .site-header.is-scrolled .nav a{color:rgba(255,255,255,.9);}
  .nav a:hover,.nav a.active{background:rgba(255,255,255,.12);color:#fff;}
  .site-header.is-scrolled .nav a:hover,.site-header.is-scrolled .nav a.active{color:#fff;background:rgba(255,255,255,.12);}
  .nav .nav-cta{margin-left:0;margin-top:14px;}
  .nav-toggle{display:block;}
  .nav-backdrop{
    position:fixed;inset:0;z-index:1090;background:rgba(10,22,52,.5);
    opacity:0;visibility:hidden;transition:opacity .3s ease;
  }
  .nav-backdrop.show{opacity:1;visibility:visible;}

  .hero{padding:120px 0 70px;}
  .hero h1{font-size:31px;}
  .hero .sub{font-size:16px;}
  .hero-stats{flex-wrap:wrap;gap:18px 0;}
  .hero-stats .hs{flex:1 1 50%;}
  .grid-3,.grid-4,.grid-2{grid-template-columns:1fr;}
  .stats{grid-template-columns:repeat(2,1fr);}
  .stat .num{font-size:30px;}
  .page-hero{padding:126px 0 56px;}
  .page-hero h1{font-size:29px;}

  .timeline::before{left:7px;transform:none;}
  .tl-item{width:100%;padding:0 0 36px 34px;text-align:left!important;}
  .tl-item:nth-child(odd){left:0;text-align:left;}
  .tl-item:nth-child(even){left:0;}
  .tl-item .dot{left:0!important;right:auto!important;}

  .news-page-item{grid-template-columns:1fr;}
  .news-page-item .n-thumb{height:190px;}
  .news-page-item .n-body{padding:20px 22px 22px;}
  .article{padding:30px 22px;}
  .form-row{grid-template-columns:1fr;}
  .cta{padding:52px 26px;}
  .cta h2{font-size:25px;}
  .footer-top{grid-template-columns:1fr;gap:32px;padding:54px 0 36px;}
  .footer-bottom{justify-content:center;text-align:center;}
}

@media (max-width:480px){
  .section-head h2{font-size:26px;}
  .hero h1{font-size:27px;}
  .hero-actions .btn{width:100%;}
  .honor-list{grid-template-columns:1fr;}
}