/* =====================================================================
   河南SNAB网络科技有限公司 · 整站基础样式 base.css
   设计体系：现代商务冷调蓝 + 纯白
   主色 #1B3A6B（深海蓝） 强调色 #2563EB（商务蓝） 浅蓝底 #EAF2FF
   说明：本文件承载全站"外壳"（顶栏/导航/页脚/悬浮条/按钮/动效）与基础原子样式，
   各页面的核心模块布局样式分别写在 css/ 目录下各自独立的页面样式文件中，
   以保证每个页面模块独立原创、不撞款。
   ===================================================================== */

/* ---------- 1. 变量与重置 ---------- */
:root{
  --c-primary:#1B3A6B;
  --c-accent:#2563EB;
  --c-accent-2:#3B82F6;
  --c-ice:#EAF2FF;
  --c-ice-2:#F6F9FE;
  --c-dark:#0F1F3D;
  --c-text:#1F2937;
  --c-text-2:#4B5A72;
  --c-muted:#75869E;
  --c-line:#DCE6F5;
  --c-white:#FFFFFF;
  --c-grad:linear-gradient(135deg,#1B3A6B 0%,#2563EB 100%);
  --c-grad-light:linear-gradient(135deg,#2563EB 0%,#3B82F6 100%);
  --radius:10px;
  --radius-lg:18px;
  --shadow:0 10px 30px rgba(27,58,107,.10);
  --shadow-lg:0 18px 48px rgba(27,58,107,.16);
  --font:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC","Helvetica Neue",Arial,sans-serif;
  --container:1200px;
  --header-h:76px;
  --trans:.35s cubic-bezier(.25,.8,.3,1);
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  font-family:var(--font);
  color:var(--c-text);
  font-size:16px;
  line-height:1.75;
  background:var(--c-white);
  overflow-x:hidden;
}
img{max-width:100%;height:auto;display:block}
a{text-decoration:none;color:inherit;transition:color var(--trans)}
ul,ol{list-style:none}
button{font-family:inherit;cursor:pointer;border:none;background:none}
input,textarea,select{font-family:inherit;font-size:inherit}
h1,h2,h3,h4,h5,h6{font-weight:700;line-height:1.3;color:var(--c-primary)}
.container{width:100%;max-width:var(--container);margin:0 auto;padding:0 20px}
::selection{background:var(--c-accent);color:#fff}

/* 滚动条 */
::-webkit-scrollbar{width:10px;height:10px}
::-webkit-scrollbar-thumb{background:linear-gradient(#2563EB,#1B3A6B);border-radius:8px}
::-webkit-scrollbar-track{background:#EEF3FB}

/* ---------- 2. 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 30px;border-radius:999px;font-size:15px;font-weight:600;
  transition:all var(--trans);white-space:nowrap;line-height:1.2;
}
.btn-primary{background:var(--c-grad);color:#fff;box-shadow:0 8px 20px rgba(37,99,235,.28)}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 14px 28px rgba(37,99,235,.38)}
.btn-line{border:2px solid var(--c-accent);color:var(--c-accent);background:transparent}
.btn-line:hover{background:var(--c-accent);color:#fff;transform:translateY(-3px)}
.btn-white{background:#fff;color:var(--c-primary);box-shadow:0 8px 20px rgba(15,31,61,.18)}
.btn-white:hover{transform:translateY(-3px);background:var(--c-ice)}
.btn-sm{padding:9px 20px;font-size:14px}
.btn-lg{padding:16px 40px;font-size:16px}
.btn-block{width:100%}

/* ---------- 3. 通用区块头 ---------- */
.sec{padding:96px 0}
.sec-head{max-width:760px;margin:0 auto 56px;text-align:center}
.sec-eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-size:13px;font-weight:700;letter-spacing:2px;color:var(--c-accent);
  background:var(--c-ice);padding:7px 18px;border-radius:999px;margin-bottom:16px;
}
.sec-eyebrow::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--c-accent)}
.sec-head h2{font-size:clamp(26px,3.2vw,38px);margin-bottom:14px}
.sec-head p{color:var(--c-text-2);font-size:16px}
.sec-head.left{text-align:left;margin-left:0}
.sec-foot{text-align:center;margin-top:44px}

/* ---------- 4. 顶栏 ---------- */
.topbar{background:var(--c-dark);color:#C7D3EA;font-size:13.5px}
.topbar-inner{display:flex;align-items:center;justify-content:space-between;min-height:40px;gap:12px}
.topbar-left{display:flex;align-items:center;gap:8px}
.topbar-left .dot{width:8px;height:8px;border-radius:50%;background:#22C55E;box-shadow:0 0 0 4px rgba(34,197,94,.18);animation:pulse 2s infinite}
@keyframes pulse{0%,100%{box-shadow:0 0 0 3px rgba(34,197,94,.15)}50%{box-shadow:0 0 0 7px rgba(34,197,94,.05)}}
.topbar-right{display:flex;align-items:center;gap:22px}
.topbar-right a{display:inline-flex;align-items:center;gap:7px;color:#C7D3EA}
.topbar-right a:hover{color:#fff}
.topbar-right .t-phone{color:#fff;font-weight:700}
.topbar svg{width:14px;height:14px;fill:#7DA6E8}

/* ---------- 5. 导航 ---------- */
.site-header{
  position:fixed;top:40px;left:0;right:0;z-index:1000;
  transition:top .35s ease,background .35s ease,box-shadow .35s ease;
  background:rgba(255,255,255,.92);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
}
.site-header.scrolled{top:0;background:#fff;box-shadow:0 6px 24px rgba(27,58,107,.10)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:var(--header-h);gap:20px}
.logo{display:flex;align-items:center;gap:10px;flex-shrink:0}
.logo img{width:190px;height:auto}
.main-nav{display:flex;align-items:center;gap:4px}
.main-nav>li{position:relative}
.main-nav>li>a{
  display:flex;align-items:center;gap:5px;padding:10px 14px;font-size:15px;font-weight:600;color:var(--c-text-2);border-radius:8px;
}
.main-nav>li>a .arr{width:9px;height:9px;border-right:2px solid currentColor;border-bottom:2px solid currentColor;transform:rotate(45deg) translateY(-2px);transition:transform var(--trans)}
.main-nav>li:hover>a,.main-nav>li.active>a{color:var(--c-accent);background:var(--c-ice)}
.main-nav>li:hover>a .arr{transform:rotate(225deg) translateY(-1px)}
.dropdown{
  position:absolute;top:calc(100% + 12px);left:50%;transform:translateX(-50%) translateY(10px);
  background:#fff;border-radius:14px;box-shadow:var(--shadow-lg);padding:14px;min-width:280px;
  opacity:0;visibility:hidden;transition:all var(--trans);z-index:99;
}
.dropdown::before{content:"";position:absolute;top:-8px;left:50%;transform:translateX(-50%);border:8px solid transparent;border-bottom-color:#fff}
.dropdown.cols2{min-width:520px;display:grid;grid-template-columns:1fr 1fr;gap:2px}
.dropdown a{
  display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:9px;font-size:14px;color:var(--c-text-2);font-weight:500;
}
.dropdown a:hover{background:var(--c-ice);color:var(--c-accent)}
.dropdown a i{
  width:32px;height:32px;border-radius:8px;background:var(--c-ice);display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;
}
.dropdown a i svg{width:16px;height:16px;fill:var(--c-accent)}
.main-nav>li:hover .dropdown{opacity:1;visibility:visible;transform:translateX(-50%) translateY(0)}
.nav-cta{display:flex;align-items:center;gap:14px;flex-shrink:0}
.nav-phone{display:flex;align-items:center;gap:10px;color:var(--c-primary)}
.nav-phone svg{width:34px;height:34px;fill:var(--c-accent)}
.nav-phone small{display:block;font-size:11px;color:var(--c-muted);line-height:1.2}
.nav-phone b{font-size:17px;line-height:1.1;letter-spacing:.5px}
.hamburger{display:none;width:42px;height:42px;border-radius:10px;background:var(--c-ice);flex-direction:column;align-items:center;justify-content:center;gap:5px}
.hamburger span{display:block;width:20px;height:2px;background:var(--c-primary);border-radius:2px;transition:all var(--trans)}
.hamburger.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.hamburger.open span:nth-child(2){opacity:0}
.hamburger.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* 移动端导航面板 */
.mobile-nav{
  position:fixed;top:0;right:0;bottom:0;width:300px;max-width:86vw;background:#fff;z-index:1200;
  transform:translateX(100%);transition:transform .4s cubic-bezier(.25,.8,.3,1);
  display:flex;flex-direction:column;box-shadow:-18px 0 48px rgba(15,31,61,.18);
}
.mobile-nav.open{transform:translateX(0)}
.mobile-nav-head{display:flex;align-items:center;justify-content:space-between;padding:18px 20px;border-bottom:1px solid var(--c-line)}
.mobile-nav-head img{width:150px}
.mnav-close{width:36px;height:36px;border-radius:9px;background:var(--c-ice);color:var(--c-primary);font-size:20px;line-height:1}
.mobile-nav-body{flex:1;overflow-y:auto;padding:14px 20px}
.mobile-nav-body>a,.mobile-nav-body>div>a{
  display:block;padding:13px 4px;font-size:15.5px;font-weight:600;color:var(--c-text-2);border-bottom:1px solid #EFF4FC;
}
.mobile-nav-body>a:hover,.mobile-nav-body>div>a:hover{color:var(--c-accent)}
.mnav-sub{margin:0 0 0 14px;display:none}
.mnav-sub.open{display:block}
.mnav-sub a{padding:9px 4px!important;font-size:14px!important;font-weight:500!important;color:var(--c-muted)!important;border-bottom:none!important}
.mnav-toggle{display:flex;justify-content:space-between;align-items:center}
.mnav-toggle .caret{width:8px;height:8px;border-right:2px solid currentColor;border-bottom:2px solid currentColor;transform:rotate(45deg);transition:transform var(--trans)}
.mnav-toggle.open .caret{transform:rotate(225deg)}
.mobile-nav-foot{padding:18px 20px;background:var(--c-ice-2);border-top:1px solid var(--c-line)}
.mobile-nav-foot a{display:flex;align-items:center;gap:10px;padding:9px 0;color:var(--c-text-2);font-size:14.5px;font-weight:600}
.mobile-nav-foot svg{width:18px;height:18px;fill:var(--c-accent)}
.nav-mask{position:fixed;inset:0;background:rgba(15,31,61,.55);z-index:1100;opacity:0;visibility:hidden;transition:all var(--trans)}
.nav-mask.open{opacity:1;visibility:visible}

/* ---------- 6. 页面横幅 ---------- */
.page-banner{
  position:relative;padding:150px 0 92px;color:#fff;background-size:cover;background-position:center;
  overflow:hidden;
}
.page-banner::before{content:"";position:absolute;inset:0;background:linear-gradient(120deg,rgba(15,31,61,.92) 0%,rgba(27,58,107,.78) 52%,rgba(37,99,235,.55) 100%)}
.page-banner::after{content:"";position:absolute;right:-120px;top:-120px;width:420px;height:420px;border-radius:50%;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12)}
.page-banner>*{position:relative;z-index:2}
.page-banner .crumb{color:#AFC6EC;font-size:14px;margin-bottom:18px;display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.page-banner .crumb a:hover{color:#fff}
.page-banner .crumb i{width:5px;height:5px;border-right:1.5px solid #8FB0E6;border-bottom:1.5px solid #8FB0E6;transform:rotate(-45deg);opacity:.7}
.page-banner h1{font-size:clamp(30px,4vw,48px);color:#fff;margin-bottom:14px;line-height:1.25}
.page-banner .banner-desc{font-size:16.5px;color:#D6E2F6;max-width:680px}
.banner-tags{display:flex;gap:10px;margin-top:24px;flex-wrap:wrap}
.banner-tags span{font-size:13px;color:#E6EEFB;background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.22);padding:6px 15px;border-radius:999px;backdrop-filter:blur(4px)}

/* ---------- 7. 联系条（页面内 CTA） ---------- */
.contact-strip{
  background:var(--c-grad);color:#fff;border-radius:var(--radius-lg);padding:44px 48px;
  display:flex;align-items:center;justify-content:space-between;gap:26px;flex-wrap:wrap;
  position:relative;overflow:hidden;
}
.contact-strip::before{content:"";position:absolute;right:-70px;top:-70px;width:240px;height:240px;border-radius:50%;background:rgba(255,255,255,.08)}
.contact-strip::after{content:"";position:absolute;left:42%;bottom:-110px;width:220px;height:220px;border-radius:50%;border:26px solid rgba(255,255,255,.06)}
.contact-strip h3{color:#fff;font-size:clamp(20px,2.4vw,27px);margin-bottom:8px}
.contact-strip p{color:#D6E2F6;font-size:15px;max-width:560px}
.contact-strip .cs-right{display:flex;align-items:center;gap:18px;flex-wrap:wrap;position:relative;z-index:2}
.contact-strip .cs-phone{display:flex;align-items:center;gap:12px}
.contact-strip .cs-phone svg{width:42px;height:42px;fill:rgba(255,255,255,.85)}
.contact-strip .cs-phone b{font-size:24px;letter-spacing:.5px;color:#fff}
.contact-strip .cs-phone small{display:block;font-size:12.5px;color:#C9DAF5}

/* ---------- 8. 页脚 ---------- */
.site-footer{background:var(--c-dark);color:#AEBED6;font-size:14.5px;margin-top:0}
.footer-top{padding:72px 0 44px;display:grid;grid-template-columns:1.35fr 1fr 1fr 1fr;gap:44px}
.footer-brand .logo{margin-bottom:18px}
.footer-brand .logo img{width:190px}
.footer-brand p{font-size:14px;line-height:1.9;color:#94A6C4;max-width:330px}
.footer-contact{margin-top:20px;display:grid;gap:10px}
.footer-contact a{display:flex;align-items:center;gap:10px;color:#C6D3EA}
.footer-contact a:hover{color:#fff}
.footer-contact svg{width:17px;height:17px;fill:#5E83C4;flex-shrink:0}
.footer-col h4{color:#fff;font-size:16.5px;margin-bottom:20px;position:relative;padding-bottom:12px}
.footer-col h4::after{content:"";position:absolute;left:0;bottom:0;width:34px;height:3px;border-radius:3px;background:var(--c-grad-light)}
.footer-col ul{display:grid;gap:11px}
.footer-col ul a{color:#9DAECE;transition:all var(--trans);display:inline-flex;align-items:center;gap:8px}
.footer-col ul a::before{content:"";width:6px;height:6px;border-radius:50%;background:#3D5E9E;transition:all var(--trans)}
.footer-col ul a:hover{color:#fff;transform:translateX(4px)}
.footer-col ul a:hover::before{background:var(--c-accent-2)}
.footer-bottom{border-top:1px solid rgba(255,255,255,.08);padding:22px 0;font-size:13.5px;color:#7E90B2}
.footer-bottom-inner{display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}
.footer-bottom .beian{display:inline-flex;align-items:center;gap:6px}
.footer-bottom .beian svg{width:14px;height:14px;fill:#7E90B2}

/* ---------- 9. 悬浮联系方式 ---------- */
.float-bar{position:fixed;right:18px;bottom:110px;z-index:900;display:flex;flex-direction:column;gap:10px}
.float-bar a,.float-bar button{
  width:46px;height:46px;border-radius:50%;display:flex;align-items:center;justify-content:center;
  background:#fff;box-shadow:0 8px 22px rgba(27,58,107,.18);position:relative;transition:all var(--trans);
}
.float-bar a:hover{transform:translateY(-3px);box-shadow:0 12px 26px rgba(37,99,235,.3)}
.float-bar svg{width:20px;height:20px;fill:var(--c-accent)}
.float-bar .fb-phone{background:var(--c-grad)}
.float-bar .fb-phone svg{fill:#fff}
.float-bar .fb-tip{
  position:absolute;right:56px;top:50%;transform:translateY(-50%) translateX(8px);white-space:nowrap;
  background:var(--c-primary);color:#fff;font-size:13px;padding:7px 14px;border-radius:8px;opacity:0;visibility:hidden;transition:all var(--trans);
}
.float-bar a:hover .fb-tip{opacity:1;visibility:visible;transform:translateY(-50%) translateX(0)}
.back-top{width:46px;height:46px;border-radius:50%;background:var(--c-ice);color:var(--c-primary);font-size:20px;line-height:1;display:flex;align-items:center;justify-content:center;transition:all var(--trans)}
.back-top:hover{background:var(--c-grad);color:#fff}

/* ---------- 10. 滚动渐入动画 ---------- */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .8s ease,transform .8s cubic-bezier(.22,.9,.3,1)}
.reveal.in{opacity:1;transform:none}
.reveal-left{opacity:0;transform:translateX(-40px);transition:all .8s cubic-bezier(.22,.9,.3,1)}
.reveal-right{opacity:0;transform:translateX(40px);transition:all .8s cubic-bezier(.22,.9,.3,1)}
.reveal-left.in,.reveal-right.in{opacity:1;transform:none}
.d1{transition-delay:.08s}.d2{transition-delay:.16s}.d3{transition-delay:.24s}.d4{transition-delay:.32s}.d5{transition-delay:.4s}

/* ---------- 11. 通用小件 ---------- */
.tag{display:inline-block;font-size:13px;font-weight:600;color:var(--c-accent);background:var(--c-ice);padding:5px 14px;border-radius:999px}
.text-accent{color:var(--c-accent)}
.text-muted{color:var(--c-muted)}
.divider{height:1px;background:var(--c-line);border:none;margin:0}
.icon-box{width:56px;height:56px;border-radius:14px;background:var(--c-ice);display:inline-flex;align-items:center;justify-content:center}
.icon-box svg{width:26px;height:26px;fill:var(--c-accent)}
.stat-num{font-size:clamp(30px,3.4vw,44px);font-weight:800;color:var(--c-primary);line-height:1}
.stat-num .unit{font-size:.55em;color:var(--c-accent);margin-left:2px}

/* 表单基础（留言页使用） */
.form-group{margin-bottom:20px}
.form-group label{display:block;font-size:14px;font-weight:600;color:var(--c-text);margin-bottom:8px}
.form-group .req{color:#EF4444}
.form-control{
  width:100%;padding:13px 16px;border:1.5px solid var(--c-line);border-radius:10px;font-size:15px;color:var(--c-text);
  background:#fff;transition:border-color var(--trans),box-shadow var(--trans);
}
.form-control:focus{outline:none;border-color:var(--c-accent);box-shadow:0 0 0 4px rgba(37,99,235,.12)}
textarea.form-control{min-height:140px;resize:vertical}

/* 面包屑可复用 */
.crumb a{color:var(--c-accent)}

/* ---------- 12. 响应式（外壳部分） ---------- */
@media (max-width:1080px){
  .main-nav{display:none}
  .nav-cta .btn{display:none}
  .hamburger{display:flex}
  .footer-top{grid-template-columns:1fr 1fr;gap:36px}
}
@media (max-width:992px){
  .topbar-left span{display:none}
  .sec{padding:72px 0}
}
@media (max-width:768px){
  :root{--header-h:64px}
  .topbar-inner{justify-content:center}
  .topbar-right{display:none}
  .site-header{top:40px}
  .logo img{width:150px}
  .page-banner{padding:130px 0 70px}
  .contact-strip{padding:32px 26px}
  .contact-strip .cs-phone b{font-size:20px}
  .footer-top{grid-template-columns:1fr;gap:30px}
  .footer-bottom{justify-content:center;text-align:center}
  .float-bar{right:10px;bottom:96px}
}
@media (max-width:520px){
  .btn{padding:11px 22px}
  .topbar{font-size:12.5px}
  .page-banner h1{font-size:26px}
  .sec-head h2{font-size:23px}
}