/* ============================================================
   novabio.top 全站设计系统  (2026-09-09 重构)
   自包含,不依赖 WordPress/Elementor 样式
   ============================================================ */

:root{
  --nb-primary:#14345C;
  --nb-primary-2:#1D4E85;
  --nb-accent:#0E8FC0;
  --nb-accent-dark:#0A6E96;
  --nb-accent-light:#E7F4FA;
  --nb-text:#2B3440;
  --nb-muted:#6B7686;
  --nb-border:#E4EAF2;
  --nb-bg-soft:#F4F8FC;
  --nb-footer-bg:#0F2440;
  --nb-white:#FFFFFF;
  --nb-radius:12px;
  --nb-shadow:0 8px 28px rgba(20,52,92,.10);
  --nb-font:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
}

*{margin:0;padding:0;box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  font-family:var(--nb-font);
  color:var(--nb-text);
  font-size:16px;
  line-height:1.7;
  background:var(--nb-white);
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;height:auto;display:block}
a{color:var(--nb-accent-dark);text-decoration:none;transition:color .15s ease}
a:hover{color:var(--nb-accent)}
ul,ol{list-style:none}

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

/* ============ 顶部信息栏 ============ */
.nb-topbar{
  background:var(--nb-primary);
  color:#fff;
  font-size:13px;
}
.nb-topbar-inner{
  display:flex;justify-content:space-between;align-items:center;
  height:38px;
}
.nb-topbar-inner a{color:#cfe4f5}
.nb-topbar-inner a:hover{color:#fff}
.nb-topbar-phone{display:flex;align-items:center;gap:6px;font-weight:500}
.nb-topbar-phone svg{flex:0 0 auto}

/* ============ 主导航 ============ */
.nb-navbar{
  background:var(--nb-white);
  border-bottom:1px solid var(--nb-border);
  position:sticky;top:0;z-index:100;
  box-shadow:0 2px 10px rgba(20,52,92,.04);
}
.nb-navbar-inner{
  display:flex;align-items:center;justify-content:space-between;
  height:72px;gap:24px;
}
.nb-brand{display:flex;align-items:center;flex:0 0 auto}
.nb-brand img{height:44px;width:auto;object-fit:contain}

.nb-menu{display:flex;align-items:center;gap:4px}
.nb-menu > li{position:relative}
.nb-menu > li > a{
  display:block;padding:10px 16px;color:var(--nb-text);
  font-size:15px;font-weight:500;border-radius:8px;white-space:nowrap;
}
.nb-menu > li > a:hover{color:var(--nb-accent-dark);background:var(--nb-accent-light)}
.nb-menu > li.active > a{color:var(--nb-accent-dark);background:var(--nb-accent-light)}
.nb-menu > li.has-sub > a::after{
  content:"";display:inline-block;width:0;height:0;margin-left:7px;
  border-left:4px solid transparent;border-right:4px solid transparent;
  border-top:5px solid currentColor;vertical-align:2px;
}
.nb-submenu{
  position:absolute;top:100%;left:0;min-width:260px;
  background:#fff;border:1px solid var(--nb-border);border-radius:10px;
  box-shadow:var(--nb-shadow);padding:8px;
  opacity:0;visibility:hidden;transform:translateY(8px);
  transition:opacity .18s ease,transform .18s ease,visibility .18s;
  z-index:101;
}
.nb-menu > li.has-sub:hover .nb-submenu,
.nb-menu > li.has-sub:focus-within .nb-submenu{
  opacity:1;visibility:visible;transform:translateY(0);
}
.nb-submenu a{
  display:block;padding:9px 14px;border-radius:7px;
  color:var(--nb-text);font-size:14px;line-height:1.4;
}
.nb-submenu a:hover{background:var(--nb-bg-soft);color:var(--nb-accent-dark)}

.nb-menu-toggle{
  display:none;flex:0 0 auto;width:44px;height:44px;
  background:var(--nb-bg-soft);border:1px solid var(--nb-border);border-radius:8px;
  cursor:pointer;align-items:center;justify-content:center;
}
.nb-menu-toggle svg{display:block}

/* ============ 按钮 ============ */
.nb-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:13px 30px;border-radius:999px;font-size:15px;font-weight:500;
  background:var(--nb-accent);color:#fff;border:1px solid var(--nb-accent);
  transition:background .18s ease,border-color .18s ease,transform .18s ease;
}
.nb-btn:hover{background:var(--nb-accent-dark);border-color:var(--nb-accent-dark);color:#fff;transform:translateY(-2px)}
.nb-btn.ghost{background:transparent;color:var(--nb-accent-dark);border-color:var(--nb-accent-dark)}
.nb-btn.ghost:hover{background:var(--nb-accent-light);color:var(--nb-accent-dark)}
.nb-btn.white{background:#fff;color:var(--nb-primary);border-color:#fff}
.nb-btn.white:hover{background:#eaf3fb;border-color:#eaf3fb;color:var(--nb-primary)}

/* ============ 首页 Hero ============ */
.nb-hero{
  background:linear-gradient(135deg,#0F2440 0%,#14345C 45%,#1D4E85 100%);
  color:#fff;position:relative;overflow:hidden;
  padding:96px 0 104px;
}
.nb-hero::after{
  content:"";position:absolute;right:-120px;top:-120px;width:420px;height:420px;
  border-radius:50%;background:radial-gradient(circle,rgba(14,143,192,.35),transparent 70%);
}
.nb-hero::before{
  content:"";position:absolute;left:-80px;bottom:-160px;width:360px;height:360px;
  border-radius:50%;background:radial-gradient(circle,rgba(14,143,192,.22),transparent 70%);
}
.nb-hero-inner{position:relative;z-index:2;max-width:820px}
.nb-hero-eyebrow{
  display:inline-block;font-size:14px;letter-spacing:.16em;
  color:#8fd0ea;margin-bottom:22px;text-transform:uppercase;
}
.nb-hero h1{
  font-size:44px;line-height:1.35;font-weight:600;margin-bottom:20px;
}
.nb-hero p{font-size:17px;color:#cfe0f0;margin-bottom:34px;max-width:640px}
.nb-hero-actions{display:flex;gap:14px;flex-wrap:wrap}

/* ============ 内页横幅 ============ */
.nb-page-banner{
  background:linear-gradient(135deg,#0F2440,#1D4E85);color:#fff;
  padding:56px 0;position:relative;overflow:hidden;
}
.nb-page-banner::after{
  content:"";position:absolute;right:-100px;top:-100px;width:300px;height:300px;
  border-radius:50%;background:radial-gradient(circle,rgba(14,143,192,.3),transparent 70%);
}
.nb-page-banner h1{font-size:34px;font-weight:600;line-height:1.3;position:relative;z-index:2}
.nb-page-banner .sub{color:#cfe0f0;font-size:15px;margin-top:10px;position:relative;z-index:2}

/* ============ 通用 section ============ */
.nb-section{padding:72px 0}
.nb-section.alt{background:var(--nb-bg-soft)}
.nb-section-head{margin-bottom:40px;text-align:center;max-width:720px;margin-left:auto;margin-right:auto}
.nb-section-head .eyebrow{display:inline-block;font-size:13px;letter-spacing:.14em;color:var(--nb-accent-dark);margin-bottom:12px;text-transform:uppercase}
.nb-section-head h2{font-size:30px;font-weight:600;color:var(--nb-primary);line-height:1.35;margin-bottom:12px}
.nb-section-head p{color:var(--nb-muted);font-size:16px}

/* 关于我们 两栏 */
.nb-about{display:grid;grid-template-columns:1.15fr 1fr;gap:56px;align-items:center}
.nb-about .eyebrow{display:inline-block;font-size:13px;letter-spacing:.14em;color:var(--nb-accent-dark);margin-bottom:12px;text-transform:uppercase}
.nb-about h2{font-size:30px;font-weight:600;color:var(--nb-primary);line-height:1.35;margin-bottom:16px}
.nb-about p{color:var(--nb-muted);font-size:16px;margin-bottom:26px}
.nb-about figure img{border-radius:var(--nb-radius);box-shadow:var(--nb-shadow);width:100%}

/* 全宽图 */
.nb-banner-img{width:100%;line-height:0}
.nb-banner-img img{width:100%;height:auto}

/* 产品特性区(文字+图交替) */
.nb-feature-row{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;margin:2em 0}
.nb-feature-row.reverse{direction:rtl}
.nb-feature-row.reverse > *{direction:ltr}
.nb-feature-row figure{margin:0;text-align:center}
.nb-feature-row figure img{border-radius:10px;box-shadow:var(--nb-shadow)}
.nb-feature-row h3{font-size:1.2rem;color:var(--nb-primary);margin-bottom:.6em}
.nb-feature-row p{color:var(--nb-text)}
@media (max-width:768px){
  .nb-about{grid-template-columns:1fr;gap:32px}
  .nb-feature-row{grid-template-columns:1fr;gap:20px}
  .nb-feature-row.reverse{direction:ltr}
}

/* ============ 卡片网格 ============ */
.nb-grid{display:grid;gap:28px}
.nb-grid.cols-2{grid-template-columns:repeat(2,1fr)}
.nb-grid.cols-3{grid-template-columns:repeat(3,1fr)}
.nb-grid.cols-4{grid-template-columns:repeat(4,1fr)}

.nb-card{
  background:#fff;border:1px solid var(--nb-border);border-radius:var(--nb-radius);
  overflow:hidden;display:flex;flex-direction:column;
  transition:transform .2s ease,box-shadow .2s ease;
}
.nb-card:hover{transform:translateY(-5px);box-shadow:var(--nb-shadow)}
.nb-card-img{aspect-ratio:16/10;overflow:hidden;background:var(--nb-bg-soft)}
.nb-card-img img{width:100%;height:100%;object-fit:cover;transition:transform .3s ease}
.nb-card:hover .nb-card-img img{transform:scale(1.05)}
.nb-card-body{padding:20px 22px 24px;flex:1;display:flex;flex-direction:column}
.nb-card-body h3{font-size:18px;font-weight:600;color:var(--nb-primary);line-height:1.4;margin-bottom:8px}
.nb-card-body p{font-size:14px;color:var(--nb-muted);line-height:1.7;flex:1}
.nb-card-link{margin-top:14px;font-size:14px;font-weight:500;color:var(--nb-accent-dark)}
.nb-card-link:hover{color:var(--nb-accent)}

/* 文章小卡片(知识中心列表) */
.nb-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:24px;margin:1.6em 0}
.nb-card.nb-article .nb-card-body{padding:16px 18px 20px}
.nb-card.nb-article .nb-card-body h3{font-size:16px;margin-bottom:6px}
.nb-card .nb-card-desc{font-size:13px;color:var(--nb-muted);line-height:1.65;margin:0}

/* ============ 内容排版 (.nb-content) ============ */
.nb-crumb{max-width:1080px;margin:0 auto;padding:20px 20px 0;font-size:13px;color:var(--nb-muted)}
.nb-crumb a{color:var(--nb-accent-dark)}
.nb-crumb a:hover{color:var(--nb-accent)}
.nb-crumb .sep{margin:0 6px;color:#c3ccd8}

.nb-content{max-width:1080px;margin:0 auto;padding:24px 20px 72px;font-size:16px;line-height:1.9;color:var(--nb-text)}
.nb-content p{margin:0 0 1.15em}
.nb-content h1{font-size:1.9rem;color:var(--nb-primary);margin:.3em 0 .8em;line-height:1.35}
.nb-content h2{font-size:1.35rem;color:var(--nb-primary);margin:1.7em 0 .7em;padding-left:.7em;border-left:4px solid var(--nb-accent);line-height:1.4}
.nb-content h3{font-size:1.12rem;color:var(--nb-primary);margin:1.4em 0 .6em}
.nb-content h4{font-size:1.05rem;color:var(--nb-primary);margin:1.2em 0 .5em}
.nb-content ul,.nb-content ol{padding-left:1.5em;margin:0 0 1.15em}
.nb-content ul{list-style:disc}
.nb-content ol{list-style:decimal}
.nb-content li{margin:.4em 0}
.nb-content strong{color:var(--nb-primary)}
.nb-content a{color:var(--nb-accent-dark)}
.nb-content a:hover{color:var(--nb-accent)}

/* 图片 */
.nb-content figure{margin:1.5em 0;text-align:center}
.nb-content figure img{border-radius:10px;box-shadow:var(--nb-shadow)}
.nb-content figcaption{font-size:.85rem;color:var(--nb-muted);margin-top:.7em}

/* 表格 */
.nb-table,.nb-content table{width:100%;border-collapse:collapse;margin:1.3em 0;font-size:.95rem;background:#fff;border-radius:10px;overflow:hidden;box-shadow:0 1px 4px rgba(20,52,92,.06)}
.nb-table th,.nb-content table th{background:var(--nb-primary);color:#fff;font-weight:600;padding:.75em 1em;text-align:left}
.nb-table td,.nb-content table td{padding:.7em 1em;border-bottom:1px solid var(--nb-border)}
.nb-table tr:last-child td,.nb-content table tr:last-child td{border-bottom:none}
.nb-table tr:nth-child(even) td,.nb-content table tr:nth-child(even) td{background:var(--nb-bg-soft)}

/* 提示块 */
.nb-note{background:var(--nb-accent-light);border-left:4px solid var(--nb-accent);border-radius:0 10px 10px 0;padding:16px 20px;margin:1.3em 0;font-size:.95rem;color:var(--nb-text)}
.nb-note strong{color:var(--nb-accent-dark)}

/* QA 问答 */
.nb-qa{margin:1em 0;padding:18px 20px;background:var(--nb-bg-soft);border:1px solid var(--nb-border);border-radius:10px}
.nb-qa .q{font-weight:600;color:var(--nb-primary);margin:0 0 .5em}
.nb-qa .a{margin:0}

/* 页脚说明 */
.nb-foot{margin-top:2.6em;padding-top:1.3em;border-top:1px solid var(--nb-border);font-size:.85rem;color:var(--nb-muted)}

/* ============ 产品特性图标列表 ============ */
.nb-features{display:grid;gap:18px;margin:1.5em 0}
.nb-feature{display:flex;gap:14px;align-items:flex-start;background:#fff;border:1px solid var(--nb-border);border-radius:10px;padding:16px 18px}
.nb-feature .ico{flex:0 0 auto;width:40px;height:40px;border-radius:10px;background:var(--nb-accent-light);color:var(--nb-accent-dark);display:flex;align-items:center;justify-content:center;font-weight:600;font-size:18px}
.nb-feature h4{font-size:16px;color:var(--nb-primary);margin-bottom:4px}
.nb-feature p{font-size:14px;color:var(--nb-muted);margin:0}

/* ============ 页脚 ============ */
.nb-footer{background:var(--nb-footer-bg);color:#c4d2e2;margin-top:0}
.nb-footer-main{display:grid;grid-template-columns:2fr 1fr 1fr 1.2fr;gap:40px;padding:56px 0 40px}
.nb-footer h4{color:#fff;font-size:15px;font-weight:600;margin-bottom:18px}
.nb-footer a{color:#c4d2e2;font-size:14px;line-height:2}
.nb-footer a:hover{color:#fff}
.nb-footer .brand-desc{font-size:14px;line-height:1.9;margin-top:14px;color:#a8bccf}
.nb-footer .brand img{height:40px;width:auto;margin-bottom:6px;filter:brightness(0) invert(1);opacity:.92}
.nb-wechat{display:flex;align-items:center;gap:12px;margin-top:16px;padding:12px 14px;background:rgba(255,255,255,.06);border-radius:10px}
.nb-wechat img{width:64px;height:64px;border-radius:8px;background:#fff;padding:3px;filter:none;opacity:1}
.nb-wechat span{font-size:13px;color:#c4d2e2;line-height:1.5}
.nb-footer-col ul li{margin-bottom:6px}
.nb-footer .addr{font-size:14px;line-height:1.9;color:#a8bccf}
.nb-footer-bottom{border-top:1px solid rgba(255,255,255,.08);padding:20px 0;font-size:13px;color:#8fa6bb;text-align:center}
.nb-footer-bottom a{color:#8fa6bb}
.nb-footer-bottom a:hover{color:#fff}

/* ============ 响应式 ============ */
@media (max-width:1024px){
  .nb-grid.cols-4{grid-template-columns:repeat(2,1fr)}
  .nb-footer-main{grid-template-columns:1fr 1fr;gap:32px}
}
@media (max-width:768px){
  .nb-hero h1{font-size:32px}
  .nb-hero{padding:64px 0 72px}
  .nb-page-banner h1{font-size:26px}
  .nb-section{padding:48px 0}
  .nb-section-head h2{font-size:24px}
  .nb-grid.cols-2,.nb-grid.cols-3,.nb-grid.cols-4{grid-template-columns:1fr}
  .nb-footer-main{grid-template-columns:1fr;gap:28px;padding:40px 0 28px}

  .nb-menu-toggle{display:flex}
  .nb-menu{
    position:absolute;top:72px;left:0;right:0;
    background:#fff;border-bottom:1px solid var(--nb-border);
    flex-direction:column;align-items:stretch;gap:0;padding:8px 16px 16px;
    box-shadow:0 12px 24px rgba(20,52,92,.10);
    display:none;
  }
  .nb-menu.open{display:flex}
  .nb-menu > li > a{padding:12px 8px;border-bottom:1px solid var(--nb-bg-soft)}
  .nb-submenu{
    position:static;opacity:1;visibility:visible;transform:none;
    box-shadow:none;border:none;padding:0 0 6px 16px;min-width:0;display:none;
  }
  .nb-menu > li.has-sub.open .nb-submenu{display:block}
  .nb-submenu a{padding:8px 0;border-bottom:1px dashed var(--nb-border);font-size:13px}
}

@media (max-width:600px){
  .nb-hero h1{font-size:26px}
  .nb-hero p{font-size:15px}
  .nb-topbar-inner span{display:none}
  .nb-content{padding:20px 14px 48px;font-size:15px}
  .nb-content h1{font-size:1.5rem}
  .nb-crumb{padding:14px 14px 0}
}