/* roulang page: index */
:root {
      --deep-space: #060B1A;
      --night-blue: #0A0E27;
      --cobalt: #1B3A5C;
      --cyan-glow: #00E5FF;
      --cyan-hover: #33EAFF;
      --text-light: #B0C4DE;
      --text-muted: #5A7A9A;
      --glass-bg: rgba(27, 58, 92, 0.25);
      --glass-border: rgba(0, 229, 255, 0.15);
      --glass-shadow: 0 8px 32px rgba(0,0,0,0.4);
      --radius-card: 16px;
      --radius-btn: 30px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-number: 'DIN Alternate', 'PingFang SC', sans-serif;
      --transition: all 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--deep-space);
      color: var(--text-light);
      margin: 0;
      line-height: 1.8;
      font-size: 16px;
      overflow-x: hidden;
      background-image: radial-gradient(circle at 30% 20%, rgba(0,229,255,0.03) 0%, transparent 50%);
    }

    a {
      color: var(--cyan-glow);
      text-decoration: none;
      transition: var(--transition);
    }
    a:hover {
      color: var(--cyan-hover);
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    button, .btn {
      font-family: inherit;
    }

    /* 左侧导航 App Shell */
    .app-sidebar {
      position: fixed;
      left: 0;
      top: 0;
      height: 100vh;
      width: 72px;
      background: rgba(10,14,39,0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-right: 1px solid rgba(0,229,255,0.1);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 24px 0;
      z-index: 1030;
      transition: width 0.25s ease;
      overflow: hidden;
    }

    .app-sidebar:hover {
      width: 220px;
    }

    .sidebar-logo {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 100%;
      padding: 0 12px;
      white-space: nowrap;
    }

    .sidebar-logo .logo-icon {
      font-size: 28px;
      color: var(--cyan-glow);
      margin-right: 8px;
      flex-shrink: 0;
    }

    .sidebar-logo .logo-text {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 20px;
      color: white;
      opacity: 0;
      transition: opacity 0.2s;
      letter-spacing: 1px;
    }

    .app-sidebar:hover .logo-text {
      opacity: 1;
    }

    .sidebar-nav {
      display: flex;
      flex-direction: column;
      gap: 24px;
      width: 100%;
      padding: 0 8px;
      margin-top: 32px;
    }

    .nav-item {
      display: flex;
      align-items: center;
      padding: 12px 16px;
      border-radius: 12px;
      color: var(--text-muted);
      transition: var(--transition);
      white-space: nowrap;
      border-left: 3px solid transparent;
      font-size: 15px;
    }

    .nav-item i {
      font-size: 20px;
      width: 24px;
      text-align: center;
      margin-right: 16px;
      flex-shrink: 0;
    }

    .nav-item span {
      opacity: 0;
      transition: opacity 0.2s;
    }

    .app-sidebar:hover .nav-item span {
      opacity: 1;
    }

    .nav-item:hover, .nav-item.active {
      color: var(--cyan-glow);
      background: rgba(0,229,255,0.08);
      border-left-color: var(--cyan-glow);
      text-shadow: 0 0 8px rgba(0,229,255,0.5);
    }

    .sidebar-footer {
      font-size: 12px;
      color: var(--text-muted);
      width: 100%;
      text-align: center;
      padding: 0 8px;
    }

    .sidebar-footer span {
      opacity: 0;
      transition: opacity 0.2s;
      white-space: nowrap;
    }

    .app-sidebar:hover .sidebar-footer span {
      opacity: 1;
    }

    /* 主内容区域 */
    .main-content {
      margin-left: 72px;
      transition: margin-left 0.25s ease;
      width: calc(100% - 72px);
    }

    /* 移动端导航 */
    .mobile-nav {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 56px;
      background: rgba(10,14,39,0.9);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      z-index: 1040;
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
      border-bottom: 1px solid rgba(0,229,255,0.15);
    }

    .mobile-logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 20px;
      color: white;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .hamburger {
      font-size: 24px;
      color: var(--cyan-glow);
      background: none;
      border: none;
    }

    .drawer-menu {
      position: fixed;
      top: 56px;
      left: 0;
      width: 100%;
      background: rgba(6,11,26,0.98);
      backdrop-filter: blur(25px);
      -webkit-backdrop-filter: blur(25px);
      padding: 24px;
      transform: translateX(-100%);
      transition: transform 0.3s ease;
      z-index: 1035;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .drawer-menu.open {
      transform: translateX(0);
    }

    .drawer-menu a {
      font-size: 20px;
      padding: 12px 0;
      border-bottom: 1px solid rgba(255,255,255,0.05);
      color: var(--text-light);
      display: block;
    }

    /* 容器 */
    .container-custom {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    section {
      padding: 100px 0;
    }

    /* 按钮 */
    .btn-primary-glow {
      background: var(--cyan-glow);
      color: var(--deep-space);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      border: none;
      box-shadow: 0 0 20px rgba(0,229,255,0.4);
      transition: var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-primary-glow:hover {
      background: var(--cyan-hover);
      box-shadow: 0 0 30px rgba(0,229,255,0.7);
      transform: scale(1.03);
      color: #060B1A;
    }

    .btn-outline-cyan {
      background: transparent;
      border: 1px solid var(--cyan-glow);
      color: var(--cyan-glow);
      font-weight: 500;
      border-radius: var(--radius-btn);
      padding: 10px 28px;
      transition: var(--transition);
    }
    .btn-outline-cyan:hover {
      background: rgba(0,229,255,0.1);
      color: var(--cyan-hover);
    }

    /* 玻璃卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: var(--glass-shadow);
      transition: var(--transition);
      padding: 28px;
    }
    .glass-card:hover {
      box-shadow: 0 12px 40px rgba(0,0,0,0.6), 0 0 18px rgba(0,229,255,0.5);
      border-color: rgba(0,229,255,0.4);
      transform: translateY(-4px);
    }

    h1, h2, h3 {
      font-family: var(--font-title);
    }
    h1 {
      font-size: 48px;
      font-weight: 700;
      color: white;
    }
    h2 {
      font-size: 36px;
      font-weight: 600;
      color: white;
      margin-bottom: 24px;
    }
    h3 {
      font-size: 22px;
      font-weight: 500;
      color: white;
    }

    .text-muted-custom {
      color: var(--text-muted);
    }

    /* Hero */
    .hero-bg {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .hero-overlay {
      background: rgba(6,11,26,0.75);
      backdrop-filter: blur(4px);
    }

    /* 案例瀑布流 */
    .masonry-grid {
      column-count: 3;
      column-gap: 24px;
    }
    .masonry-item {
      break-inside: avoid;
      margin-bottom: 24px;
    }

    /* FAQ */
    .accordion-faq .accordion-button {
      background: transparent;
      color: white;
      font-weight: 500;
      border-left: 3px solid var(--cyan-glow);
      padding-left: 20px;
    }
    .accordion-faq .accordion-button:not(.collapsed) {
      background: rgba(0,229,255,0.05);
      color: var(--cyan-glow);
    }

    @media (max-width: 991px) {
      .app-sidebar {
        display: none;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .mobile-nav {
        display: flex;
      }
      .main-content {
        padding-top: 56px;
      }
      section {
        padding: 60px 0;
      }
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
    }

    @media (max-width: 767px) {
      .masonry-grid {
        column-count: 1;
      }
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      .container-custom {
        padding: 0 16px;
      }
    }