/* roulang page: index */
:root {
      --deep-blue: #0A0F24;
      --card-bg: #0D152E;
      --cyan: #00E5FF;
      --amber: #FFB300;
      --white90: rgba(240, 242, 245, 0.9);
      --muted: #8A8F9E;
      --border-color: #1A2035;
      --cyan-glow: 0 0 18px rgba(0, 229, 255, 0.5);
      --cyan-glow-hover: 0 0 30px rgba(0, 229, 255, 0.7);
      --amber-glow: 0 0 18px rgba(255, 179, 0, 0.5);
      --glass-bg: rgba(13, 21, 46, 0.7);
      --glass-border: 1px solid rgba(0, 229, 255, 0.15);
      --radius-lg: 16px;
      --radius-btn: 50px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--deep-blue);
      color: var(--white90);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
    }
    h1, h2, h3, h4, h5, h6 {
      font-weight: 700;
      letter-spacing: 0.02em;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: all 0.25s ease;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    /* 自定义容器微调 */
    .container-custom {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    section {
      padding: 100px 0;
      position: relative;
    }
    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
    }

    /* 导航栏 - 暗色霓虹固定顶栏 */
    .navbar {
      background-color: rgba(10, 15, 36, 0.95);
      backdrop-filter: blur(15px);
      border-bottom: 2px solid var(--cyan);
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
      padding: 0.8rem 0;
      transition: all 0.3s;
    }
    .navbar-brand {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--cyan) !important;
      letter-spacing: 2px;
      text-shadow: 0 0 12px rgba(0, 229, 255, 0.4);
    }
    .navbar-nav .nav-link {
      color: var(--white90) !important;
      font-weight: 500;
      margin: 0 6px;
      padding: 8px 14px !important;
      border-radius: 20px;
      position: relative;
      transition: 0.2s;
    }
    .navbar-nav .nav-link:hover {
      color: var(--cyan) !important;
      text-shadow: 0 0 8px var(--cyan);
    }
    .navbar-nav .nav-link.active {
      color: var(--cyan) !important;
      background: rgba(0, 229, 255, 0.08);
      box-shadow: 0 0 12px rgba(0, 229, 255, 0.4);
      font-weight: 600;
    }
    .nav-cta-btn {
      background: var(--amber);
      color: #0A0F24 !important;
      font-weight: 700;
      padding: 10px 26px !important;
      border-radius: 50px;
      margin-left: 12px;
      box-shadow: var(--amber-glow);
      border: none;
      transition: 0.25s;
    }
    .nav-cta-btn:hover {
      background: #ffc107;
      box-shadow: 0 0 28px rgba(255, 179, 0, 0.8);
      transform: translateY(-1px);
    }
    .navbar-toggler {
      border: 1px solid var(--cyan);
      padding: 6px 10px;
    }
    .navbar-toggler-icon {
      background-image: none;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      color: var(--cyan);
      font-size: 1.6rem;
    }
    .navbar-toggler-icon::before {
      content: "\f0c9";
      font-family: "Font Awesome 6 Free";
      font-weight: 900;
      color: var(--cyan);
    }
    @media (max-width: 992px) {
      .navbar-nav {
        background: rgba(10, 15, 36, 0.98);
        backdrop-filter: blur(20px);
        padding: 20px;
        border-radius: 20px;
        margin-top: 10px;
      }
      .nav-cta-btn {
        margin-left: 0;
        margin-top: 10px;
        text-align: center;
        display: inline-block;
      }
    }

    /* 按钮全局 */
    .btn-primary-cyan {
      background: var(--cyan);
      color: #0A0F24;
      font-weight: 700;
      border: none;
      border-radius: var(--radius-btn);
      padding: 14px 38px;
      box-shadow: var(--cyan-glow);
      transition: 0.3s;
      letter-spacing: 0.5px;
    }
    .btn-primary-cyan:hover {
      background: #00ffff;
      box-shadow: var(--cyan-glow-hover);
      transform: translateY(-2px);
      color: #000;
    }
    .btn-outline-cyan {
      background: transparent;
      border: 2px solid var(--cyan);
      color: var(--cyan);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 14px 38px;
      transition: 0.3s;
    }
    .btn-outline-cyan:hover {
      background: rgba(0, 229, 255, 0.15);
      color: white;
      box-shadow: 0 0 16px rgba(0, 229, 255, 0.4);
    }
    .btn-amber {
      background: var(--amber);
      color: #0A0F24;
      font-weight: 700;
      border-radius: 50px;
      padding: 14px 40px;
      box-shadow: var(--amber-glow);
      border: none;
      transition: 0.3s;
    }
    .btn-amber:hover {
      background: #ffb300;
      box-shadow: 0 0 28px rgba(255,179,0,0.8);
      transform: scale(1.02);
    }

    /* Hero */
    #hero {
      padding-top: 140px;
      padding-bottom: 100px;
    }
    .hero-title {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.3;
      color: white;
      text-shadow: 0 0 20px rgba(0,229,255,0.3);
    }
    .hero-sub {
      font-size: 1.2rem;
      font-weight: 300;
      color: var(--muted);
      margin: 1.5rem 0 2rem;
    }
    .hero-image-wrapper {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: var(--glass-border);
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2.5rem;
      }
      #hero {
        padding-top: 120px;
      }
    }

    /* 亮点网格 */
    .highlight-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: var(--glass-border);
      border-radius: var(--radius-lg);
      padding: 40px 25px;
      text-align: center;
      transition: 0.3s;
    }
    .highlight-card:hover {
      border-color: rgba(0,229,255,0.35);
      transform: translateY(-6px);
      box-shadow: 0 16px 35px rgba(0,0,0,0.5);
    }
    .icon-circle {
      width: 70px;
      height: 70px;
      background: rgba(0,229,255,0.12);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 20px;
      color: var(--cyan);
      font-size: 2rem;
      box-shadow: 0 0 18px rgba(0,229,255,0.3);
    }
    .highlight-title {
      font-size: 1.4rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .cyan-line {
      width: 50px;
      height: 3px;
      background: var(--cyan);
      margin: 15px auto;
      box-shadow: 0 0 10px var(--cyan);
    }

    /* 案例瀑布 */
    .case-grid {
      columns: 2;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: var(--glass-border);
      border-radius: var(--radius-lg);
      overflow: hidden;
      margin-bottom: 24px;
      transition: 0.25s;
    }
    .case-card:hover {
      border-color: rgba(0,229,255,0.4);
      transform: translateY(-5px);
      box-shadow: 0 15px 30px rgba(0,0,0,0.6);
    }
    .case-img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    .case-content {
      padding: 20px;
    }
    .case-tag {
      display: inline-block;
      border: 1px solid var(--amber);
      color: var(--amber);
      font-size: 0.8rem;
      padding: 4px 14px;
      border-radius: 30px;
      margin-bottom: 10px;
      font-weight: 500;
    }
    @media (max-width: 768px) {
      .case-grid {
        columns: 1;
      }
    }

    /* 方案对比 */
    .compare-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      padding: 35px 25px;
      height: 100%;
      border: 1px solid rgba(255,255,255,0.08);
    }
    .pro-card {
      border: 1px solid var(--cyan);
      box-shadow: 0 0 25px rgba(0,229,255,0.3);
      position: relative;
    }
    .badge-recommend {
      background: var(--amber);
      color: #0A0F24;
      font-weight: 700;
      padding: 5px 18px;
      border-radius: 30px;
      font-size: 0.9rem;
      position: absolute;
      top: -14px;
      right: 20px;
      box-shadow: var(--amber-glow);
    }
    .check-icon {
      color: var(--cyan);
      margin-right: 10px;
    }
    .minus-icon {
      color: #6c757d;
      margin-right: 10px;
    }

    /* FAQ 手风琴 */
    .accordion-button {
      background: #0D152E;
      color: var(--white90);
      font-weight: 600;
      border: none;
      box-shadow: none;
      padding: 1.2rem 1.5rem;
      border-radius: 12px !important;
    }
    .accordion-button:not(.collapsed) {
      background: #0D152E;
      color: var(--cyan);
      box-shadow: none;
      border-left: 4px solid var(--cyan);
    }
    .accordion-item {
      background: transparent;
      border: 1px solid var(--border-color);
      margin-bottom: 16px;
      border-radius: 12px;
      overflow: hidden;
    }
    .accordion-body {
      background: #141b2e;
      color: var(--white90);
    }

    /* CTA 横幅 */
    .cta-banner {
      background: #0A0F24;
      background-image: radial-gradient(rgba(0,229,255,0.08) 1px, transparent 1px);
      background-size: 30px 30px;
      padding: 90px 0;
    }
    .pulse-btn {
      animation: pulseGlow 2s infinite;
    }
    @keyframes pulseGlow {
      0% { box-shadow: 0 0 18px rgba(0,229,255,0.5); }
      50% { box-shadow: 0 0 35px rgba(0,229,255,0.9); }
      100% { box-shadow: 0 0 18px rgba(0,229,255,0.5); }
    }

    /* 页脚 */
    .footer {
      background: #060A18;
      border-top: 1px solid var(--cyan);
      padding: 60px 0 30px;
    }
    .social-icon {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 42px;
      height: 42px;
      border: 1px solid var(--muted);
      border-radius: 50%;
      color: var(--muted);
      margin-right: 12px;
      transition: 0.25s;
    }
    .social-icon:hover {
      border-color: var(--cyan);
      color: var(--cyan);
      background: rgba(0,229,255,0.1);
      box-shadow: 0 0 15px var(--cyan);
    }