:root {
    --primary: #1a4f8b;
    --primary-light: #2c6cab;
    --primary-dark: #0d3266;
    --accent: #d4a017;
    --accent-light: #e8c040;
    --bg-light: #f7f9fc;
    --text-dark: #1a1a2e;
    --text-gray: #5a6273;
    --white: #ffffff;
    --shadow: 0 4px 24px rgba(26, 79, 139, 0.08);
    --shadow-hover: 0 8px 40px rgba(26, 79, 139, 0.15);
  }
  * { margin: 0; padding: 0; box-sizing: border-box; }
  body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    color: var(--text-dark);
    background: var(--white);
    line-height: 1.7;
  }
  .navbar {
    position: fixed; top: 0; left: 0; width: 100%; height: 76px;
    background: rgba(255, 255, 255, 0.97); backdrop-filter: blur(12px);
    box-shadow: 0 1px 12px rgba(0, 0, 0, 0.06); z-index: 1000;
    display: flex; align-items: center; justify-content: space-between; padding: 0 5%;
  }
  .navbar .logo img { height: 46px; object-fit: contain; }
  .nav-links { display: flex; gap: 36px; list-style: none; }
  .nav-links a {
    text-decoration: none; color: var(--text-dark); font-size: 15px;
    font-weight: 500; transition: color 0.3s; position: relative;
  }
  .nav-links a:hover, .nav-links a.active { color: var(--primary); }
  .nav-links a::after {
    content: ''; position: absolute; bottom: -6px; left: 0; width: 0; height: 2px;
    background: var(--accent); transition: width 0.3s;
  }
  .nav-links a:hover::after, .nav-links a.active::after { width: 100%; }
  .nav-right { display: flex; align-items: center; gap: 20px; }
  .nav-phone { font-size: 18px; font-weight: 700; color: var(--primary); text-decoration: none; white-space: nowrap; display: flex; align-items: center; gap: 6px; }
  .nav-phone i { color: var(--accent); font-size: 16px; }
  .nav-cta {
    background: var(--primary); color: var(--white); padding: 8px 24px;
    border-radius: 6px; font-size: 14px; text-decoration: none; transition: background 0.3s;
  }
  .nav-cta:hover { background: var(--primary-dark); }
  .nav-toggle { display: none; background: none; border: none; font-size: 24px; color: var(--primary); cursor: pointer; padding: 4px 8px; }

  /* 页面头部 Banner */
  .page-header {
    margin-top: 76px; padding: 100px 5% 70px; text-align: center;
    background: var(--primary-dark); position: relative; overflow: hidden;
  }
  .page-header::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0;
    background-image:
      radial-gradient(circle at 20% 30%, rgba(212, 160, 23, 0.10) 0%, transparent 50%),
      radial-gradient(circle at 80% 70%, rgba(212, 160, 23, 0.06) 0%, transparent 40%);
    pointer-events: none;
  }
  .page-header-content { position: relative; z-index: 2; max-width: 700px; margin: 0 auto; }
  .page-header .sub-tagline { font-size: 14px; color: var(--accent-light); margin-bottom: 12px; letter-spacing: 6px; }
  .page-header h1 { font-size: 36px; font-weight: 700; color: var(--white); margin-bottom: 16px; letter-spacing: 3px; }
  .page-header p { font-size: 16px; color: rgba(255, 255, 255, 0.8); letter-spacing: 1px; }

  .section { padding: 80px 5%; scroll-margin-top: 76px; }
  .section-light { background: var(--white); }
  .section-gray { background: var(--bg-light); }
  .section-dark { background: var(--primary-dark); }
  .section-title { text-align: center; margin-bottom: 12px; }
  .section-title h2 { font-size: 32px; font-weight: 700; color: var(--text-dark); letter-spacing: 3px; }
  .section-dark .section-title h2 { color: var(--white); }
  .section-title .divider { width: 60px; height: 4px; background: var(--accent); margin: 16px auto 24px; border-radius: 2px; }
  .section-subtitle { text-align: center; font-size: 15px; color: var(--text-gray); margin-bottom: 50px; max-width: 700px; margin-left: auto; margin-right: auto; }

  /* 概览卡片 */
  .overview-grid { max-width: 1200px; margin: 0 auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
  .overview-card {
    background: var(--white); border-radius: 14px; padding: 36px 28px; text-decoration: none;
    box-shadow: var(--shadow); transition: all 0.3s; border-top: 4px solid transparent; text-align: center;
  }
  .overview-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); border-top-color: var(--accent); }
  .overview-card .ov-icon { width: 60px; height: 60px; margin: 0 auto 20px; border-radius: 14px; background: linear-gradient(135deg, var(--primary), var(--primary-light)); display: flex; align-items: center; justify-content: center; font-size: 26px; color: var(--white); }
  .overview-card h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; color: var(--text-dark); }
  .overview-card p { font-size: 13px; color: var(--text-gray); line-height: 1.6; margin-bottom: 16px; }
  .overview-card .ov-link { font-size: 13px; color: var(--primary); font-weight: 600; display: inline-flex; align-items: center; gap: 6px; }
  .overview-card .ov-link i { transition: transform 0.3s; }
  .overview-card:hover .ov-link i { transform: translateX(4px); }

  /* 板块详情 */
  .biz-detail { max-width: 1100px; margin: 0 auto; }
  .biz-header { text-align: center; margin-bottom: 36px; }
  .biz-header .biz-icon-lg { width: 72px; height: 72px; margin: 0 auto 20px; border-radius: 18px; background: linear-gradient(135deg, var(--primary), var(--primary-light)); display: flex; align-items: center; justify-content: center; font-size: 32px; color: var(--white); box-shadow: 0 8px 28px rgba(26, 79, 139, 0.25); }
  .biz-header h2 { font-size: 28px; font-weight: 700; color: var(--text-dark); letter-spacing: 2px; margin-bottom: 8px; }
  .biz-header .biz-tagline { font-size: 15px; color: var(--accent); font-weight: 600; }

  .biz-intro { max-width: 800px; margin: 0 auto 40px; text-align: center; }
  .biz-intro p { font-size: 16px; color: var(--text-gray); line-height: 2; text-indent: 2em; }

  .biz-content { display: grid; grid-template-columns: 1.8fr 1fr; gap: 24px; margin-bottom: 40px; }
  .biz-block { background: var(--white); border-radius: 12px; padding: 32px 28px; box-shadow: var(--shadow); border-top: 3px solid var(--primary); }
  .section-gray .biz-block { background: var(--white); }
  .biz-block h3 { font-size: 16px; font-weight: 700; color: var(--primary); margin-bottom: 18px; display: flex; align-items: center; gap: 8px; }
  .biz-block h3 i { color: var(--accent); }
  .biz-product-list, .biz-scenario-list { list-style: none; }
  .biz-product-list li, .biz-scenario-list li {
    display: flex; align-items: flex-start; gap: 10px; margin-bottom: 14px;
    font-size: 14px; color: var(--text-dark); line-height: 1.7;
  }
  .biz-product-list li i, .biz-scenario-list li i { color: var(--accent); font-size: 14px; margin-top: 5px; flex-shrink: 0; }
  .biz-product-list .biz-prod-desc { color: var(--text-gray); font-size: 13px; margin-left: 6px; line-height: 1.6; flex: 1; min-width: 0; }
  .biz-product-list .biz-prod-name { font-weight: 600; white-space: nowrap; flex-shrink: 0; }

  /* 联系我们 */
  .contact-wrap { max-width: 900px; margin: 0 auto; }
    #contact { padding-top: 52px; padding-bottom: 52px; }
  .contact-layout { display: grid; grid-template-columns: 1.5fr 1fr; gap: 50px; align-items: center; }
  .contact-info h2 { font-size: 28px; color: var(--white); margin-bottom: 12px; letter-spacing: 3px; }
  .contact-info > p { color: rgba(255, 255, 255, 0.7); margin-bottom: 32px; font-size: 15px; }
  .contact-list { display: flex; flex-direction: column; gap: 18px; }
  .contact-row { display: flex; align-items: flex-start; gap: 14px; }
  .contact-row i { font-size: 18px; color: var(--accent); margin-top: 2px; flex-shrink: 0; }
  .contact-row .c-detail { flex: 1; }
  .contact-row .label { font-size: 12px; color: rgba(255, 255, 255, 0.5); margin-bottom: 3px; }
  .contact-row .value { font-size: 16px; color: var(--white); font-weight: 500; line-height: 1.5; }
  .contact-qr { text-align: center; }
  .contact-qr .qr-frame { display: inline-block; padding: 12px; background: rgba(255,255,255,0.08); border: 1px solid rgba(255,255,255,0.15); border-radius: 16px; }
  .contact-qr .qr-frame img { width: 160px; height: 160px; border-radius: 8px; display: block; }
  .contact-qr .qr-label { margin-top: 14px; font-size: 14px; color: var(--white); font-weight: 600; }
  .contact-qr .qr-sub { margin-top: 4px; font-size: 12px; color: rgba(255, 255, 255, 0.5); }

  /* 润网服务价值 */
  .biz-value {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
    border-radius: 16px; padding: 40px 36px; position: relative; overflow: hidden;
  }
  .biz-value::before {
    content: ''; position: absolute; top: 0; right: 0; width: 200px; height: 200px;
    background: radial-gradient(circle, rgba(212,160,23,0.10) 0%, transparent 70%); pointer-events: none;
  }
  .biz-value-title { display: flex; align-items: center; gap: 12px; margin-bottom: 28px; position: relative; z-index: 1; }
  .biz-value-title i { font-size: 22px; color: var(--accent); }
  .biz-value-title h3 { font-size: 20px; font-weight: 700; color: var(--white); letter-spacing: 2px; }
  .biz-value-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; position: relative; z-index: 1; }
  .biz-value-item { background: rgba(255, 255, 255, 0.08); border-radius: 10px; padding: 24px 22px; border-left: 3px solid var(--accent); transition: all 0.3s; }
  .biz-value-item:hover { background: rgba(212, 160, 23, 0.12); }
  .biz-value-item h4 { font-size: 15px; font-weight: 700; color: var(--white); margin-bottom: 8px; display: flex; align-items: center; gap: 8px; }
  .biz-value-item h4 i { color: var(--accent-light); font-size: 15px; }
  .biz-value-item p { font-size: 13px; color: rgba(255, 255, 255, 0.75); line-height: 1.8; }
  .biz-sla {
    margin-top: 24px; padding: 16px 24px; background: rgba(212, 160, 23, 0.15);
    border-radius: 10px; border: 1px solid rgba(212, 160, 23, 0.35);
    display: flex; align-items: center; gap: 12px; position: relative; z-index: 1;
  }
  .biz-sla i { color: var(--accent); font-size: 18px; flex-shrink: 0; }
  .biz-sla span { font-size: 14px; color: rgba(255, 255, 255, 0.88); font-weight: 500; }
  .biz-sla .sla-label { color: var(--accent-light); font-weight: 700; margin-right: 4px; }


  /* 板块快捷导航 - 浮动侧边 */
  .biz-quicknav {
    position: fixed; right: 20px; top: 50%; transform: translateY(-50%);
    z-index: 900; display: flex; flex-direction: column; gap: 6px;
  }
  .biz-quicknav a {
    display: flex; align-items: center; gap: 8px; padding: 9px 16px;
    border-radius: 20px; font-size: 13px; color: var(--text-gray);
    text-decoration: none; background: rgba(255,255,255,0.92);
    box-shadow: 0 2px 10px rgba(0,0,0,0.08); transition: all 0.3s;
    white-space: nowrap; backdrop-filter: blur(8px); border: 1px solid rgba(0,0,0,0.04);
  }
  .biz-quicknav a:hover { background: var(--primary); color: var(--white); transform: translateX(-4px); }
  .biz-quicknav a.active { background: var(--primary); color: var(--white); }
  .biz-quicknav a .qn-dot {
    width: 6px; height: 6px; border-radius: 50%; background: var(--accent);
    flex-shrink: 0; transition: all 0.3s;
  }
  .biz-quicknav a.active .qn-dot { background: var(--accent-light); transform: scale(1.3); }
  .biz-quicknav a .qn-label { font-weight: 500; }

  footer { background: var(--primary-dark); padding: 30px 5%; text-align: center; }
  footer p { color: rgba(255, 255, 255, 0.5); font-size: 13px; }
  footer a { color: inherit; }

  /* 平板 */
  @media (max-width: 900px) {
    .nav-links { display: none; }
    .nav-toggle { display: block; }
    .overview-grid { grid-template-columns: repeat(2, 1fr); }
    .biz-content { grid-template-columns: 1fr; }
    .biz-value-grid { grid-template-columns: 1fr; }
    .page-header h1 { font-size: 28px; }
    .section { padding: 60px 4%; }
    .section-title h2 { font-size: 26px; }
    .biz-quicknav { right: 12px; }
    .biz-quicknav a { padding: 7px 10px; font-size: 12px; }
    .biz-quicknav a .qn-label { display: none; }
  }
  /* 手机 */
  @media (max-width: 600px) {
    .navbar { height: 60px; padding: 0 3%; }
    .navbar .logo img { height: 34px; }
    .nav-phone { font-size: 14px; }
    .nav-phone i { font-size: 12px; }
    .nav-cta { padding: 6px 16px; font-size: 12px; }
    .page-header { margin-top: 60px; padding: 60px 5% 50px; }
    .page-header h1 { font-size: 22px; letter-spacing: 2px; }
    .page-header p { font-size: 14px; }
    .section { padding: 48px 5%; }
    .section-title h2 { font-size: 22px; letter-spacing: 2px; }
    .section-subtitle { font-size: 13px; margin-bottom: 36px; }
    .overview-grid { grid-template-columns: 1fr; gap: 16px; }
    .contact-layout { grid-template-columns: 1fr; gap: 36px; text-align: center; }
    .contact-list { align-items: center; }
    .overview-card { padding: 28px 22px; }
    .overview-card .ov-icon { width: 50px; height: 50px; font-size: 22px; }
    .overview-card h3 { font-size: 16px; }
    .overview-card p { font-size: 12px; }
    .biz-header .biz-icon-lg { width: 56px; height: 56px; font-size: 24px; }
    .biz-header h2 { font-size: 22px; }
    .biz-header .biz-tagline { font-size: 13px; }
    .biz-intro p { font-size: 14px; }
    .biz-block { padding: 24px 20px; }
    .biz-product-list li, .biz-scenario-list li { font-size: 13px; }
    .biz-value { padding: 28px 20px; }
    .biz-value-title h3 { font-size: 17px; }
    .biz-value-grid { grid-template-columns: 1fr; gap: 14px; }
    .biz-value-item { padding: 18px 16px; }
    .biz-value-item h4 { font-size: 14px; }
    .biz-value-item p { font-size: 12px; }
    .biz-sla { padding: 12px 16px; }
    .biz-sla span { font-size: 12px; }
    .contact-layout { gap: 30px; text-align: center; }
    .contact-list { align-items: center; }
    .contact-row { flex-direction: column; gap: 4px; align-items: center; }
    .contact-row .value { font-size: 14px; }
    footer p { font-size: 12px; }
    .biz-quicknav { display: none; }
  }
  /* 手机导航展开 */
  .nav-links.mobile-open {
    display: flex !important;
    position: absolute; top: 60px; left: 0; right: 0;
    flex-direction: column; gap: 0; background: rgba(255,255,255,0.98);
    box-shadow: 0 4px 16px rgba(0,0,0,0.1);
    padding: 0; margin: 0;
  }
  .nav-links.mobile-open li { padding: 14px 5%; border-bottom: 1px solid #eef0f4; }
  .nav-links.mobile-open a { font-size: 15px; }

  /* 免费咨询二维码弹窗 */
  .qr-modal-overlay {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0, 0, 0, 0.5); z-index: 9999;
    display: none; align-items: center; justify-content: center;
    backdrop-filter: blur(4px);
  }
  .qr-modal-overlay.show { display: flex; }
  .qr-modal {
    background: #fff; border-radius: 20px; padding: 40px 36px 32px;
    max-width: 320px; width: 88%; text-align: center; position: relative;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: modalIn 0.3s ease;
  }
  @keyframes modalIn {
    from { opacity: 0; transform: scale(0.9) translateY(20px); }
    to { opacity: 1; transform: scale(1) translateY(0); }
  }
  .qr-modal-close {
    position: absolute; top: 16px; right: 16px;
    width: 32px; height: 32px; border-radius: 50%;
    background: #f0f0f0; border: none; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    font-size: 16px; color: #999; transition: all 0.3s;
  }
  .qr-modal-close:hover { background: #e0e0e0; color: #666; }
  .qr-modal h3 { font-size: 22px; font-weight: 700; color: #0d3266; margin-bottom: 8px; }
  .qr-modal .qr-modal-sub { font-size: 13px; color: #999; margin-bottom: 24px; }
  .qr-modal-img { width: 200px; height: 200px; margin: 0 auto 20px; border-radius: 12px; border: 1px solid #eef0f4; }
  .qr-modal-tip { font-size: 14px; color: #666; margin-bottom: 4px; }
  .qr-modal-tip span { color: #1a4f8b; font-weight: 600; }
  .qr-modal-desc { font-size: 12px; color: #aaa; }