/* roulang page: index */
:root {
      --primary: #FF6B2C;
      --primary-glow: #FF7A45;
      --accent: #00F0FF;
      --bg-deep: #0F0F1A;
      --bg-card: #1A1A2E;
      --bg-surface: #161625;
      --text-body: #E0E0E0;
      --text-title: #FFFFFF;
      --text-muted: #A0A0B0;
      --border-subtle: rgba(255,107,44,0.2);
      --border-glow: rgba(0,240,255,0.25);
      --shadow-card: 0 8px 24px rgba(0,0,0,0.45);
      --radius-card: 16px;
      --radius-btn: 8px;
      --font-sans: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      --transition: 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-deep);
      color: var(--text-body);
      line-height: 1.8;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4, h5 {
      font-weight: 700;
      color: var(--text-title);
      letter-spacing: -0.2px;
    }

    h1 {
      font-size: clamp(2.5rem, 6vw, 4.2rem);
      font-weight: 800;
      line-height: 1.2;
    }

    h2 {
      font-size: clamp(2rem, 5vw, 2.8rem);
      margin-bottom: 1rem;
    }

    h3 {
      font-size: 1.75rem;
      font-weight: 600;
    }

    .section-padding {
      padding: 5rem 0;
    }

    @media (max-width: 768px) {
      .section-padding {
        padding: 3.5rem 0;
      }
    }

    /* 导航栏 */
    .navbar-custom {
      background: rgba(15, 15, 26, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-subtle);
      padding: 0.75rem 0;
      transition: var(--transition);
    }

    .navbar-brand {
      font-weight: 800;
      font-size: 1.8rem;
      color: var(--text-title) !important;
      letter-spacing: -0.5px;
      transition: var(--transition);
    }

    .navbar-brand span {
      color: var(--primary);
    }

    .navbar-nav .nav-link {
      color: #CCCCCC !important;
      font-weight: 500;
      margin: 0 0.5rem;
      padding: 0.5rem 0.8rem;
      position: relative;
      transition: color 0.2s;
    }

    .navbar-nav .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0.8rem;
      right: 0.8rem;
      height: 2px;
      background: var(--accent);
      transform: scaleX(0);
      transition: transform 0.3s ease;
    }

    .navbar-nav .nav-link:hover,
    .navbar-nav .nav-link.active {
      color: #FFFFFF !important;
    }

    .navbar-nav .nav-link:hover::after,
    .navbar-nav .nav-link.active::after {
      transform: scaleX(1);
      box-shadow: 0 0 12px var(--accent);
    }

    .btn-neon-nav {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: 30px;
      padding: 0.4rem 1.8rem;
      font-weight: 600;
      transition: 0.25s;
    }

    .btn-neon-nav:hover {
      background: var(--primary);
      color: #fff;
      box-shadow: 0 0 18px rgba(255,107,44,0.5);
    }

    /* 汉堡菜单图标自定义 */
    .navbar-toggler {
      border: none;
      color: var(--text-title);
    }

    .navbar-toggler-icon {
      background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3E%3Cpath stroke='rgba(255,255,255,0.8)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3E%3C/svg%3E");
    }

    /* Hero 双栏 */
    .hero-section {
      min-height: 85vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 20% 30%, #2a1a3a 0%, #0F0F1A 80%);
    }

    .hero-image {
      border-radius: 28px;
      box-shadow: 0 0 40px rgba(0,240,255,0.25);
      width: 100%;
      height: auto;
      object-fit: cover;
      transition: var(--transition);
    }

    .highlight {
      color: var(--primary);
    }

    .btn-primary-glow {
      background: linear-gradient(135deg, #FF6B2C, #FF8A4C);
      border: none;
      color: white;
      font-weight: 600;
      padding: 0.8rem 2.2rem;
      border-radius: var(--radius-btn);
      box-shadow: 0 8px 18px rgba(255,107,44,0.4);
      transition: var(--transition);
      letter-spacing: 0.3px;
    }

    .btn-primary-glow:hover {
      filter: brightness(1.15);
      box-shadow: 0 0 28px rgba(255,107,44,0.7);
      transform: translateY(-2px);
      color: white;
    }

    .btn-outline-neon {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 0.75rem 2rem;
      border-radius: var(--radius-btn);
      transition: var(--transition);
    }

    .btn-outline-neon:hover {
      background: rgba(255,107,44,0.1);
      border-color: var(--accent);
      color: var(--accent);
      box-shadow: 0 0 15px rgba(0,240,255,0.4);
    }

    /* 核心优势网格 */
    .feature-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 2rem 1.8rem;
      border-left: 4px solid var(--primary);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      height: 100%;
      background: linear-gradient(145deg, #1E1E30 0%, #18182A 100%);
    }

    .feature-card:hover {
      background: #222240;
      border-left-color: var(--accent);
      box-shadow: 0 12px 28px rgba(0,0,0,0.6);
      transform: translateY(-5px);
    }

    .feature-icon {
      color: var(--primary);
      margin-bottom: 1.5rem;
    }

    /* 案例瀑布流 */
    .masonry-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }

    @media (max-width: 992px) {
      .masonry-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .masonry-grid {
        grid-template-columns: 1fr;
      }
    }

    .case-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid rgba(255,107,44,0.1);
    }

    .case-card:hover {
      border-color: var(--accent);
      box-shadow: 0 16px 32px rgba(0,0,0,0.5);
      transform: translateY(-6px);
    }

    .case-img {
      width: 100%;
      height: 220px;
      object-fit: cover;
      transition: transform 0.4s;
    }

    .case-card:hover .case-img {
      transform: scale(1.05);
    }

    .case-content {
      padding: 1.5rem;
    }

    .case-tag {
      background: rgba(255,107,44,0.15);
      color: var(--primary);
      padding: 0.2rem 1rem;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 0.8rem;
    }

    .case-title {
      font-size: 1.4rem;
      margin-bottom: 0.5rem;
      transition: color 0.2s;
    }

    .case-card:hover .case-title {
      text-decoration: underline;
      text-decoration-color: var(--accent);
      text-underline-offset: 6px;
      text-decoration-thickness: 2px;
    }

    /* 方案对比 */
    .plan-card {
      background: #1A1A2E;
      border-radius: 20px;
      padding: 2.5rem 2rem;
      border: 1px solid rgba(255,255,255,0.08);
      transition: var(--transition);
      height: 100%;
      display: flex;
      flex-direction: column;
    }

    .plan-highlight {
      border: 2px solid var(--primary);
      box-shadow: 0 0 30px rgba(255,107,44,0.3);
      position: relative;
    }

    .badge-hot {
      background: var(--primary);
      color: white;
      border-radius: 30px;
      padding: 0.3rem 1.4rem;
      font-size: 0.8rem;
      font-weight: 700;
      position: absolute;
      top: -12px;
      right: 20px;
    }

    .plan-list {
      list-style: none;
      padding-left: 0;
    }

    .plan-list li {
      padding: 0.25rem 0;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }

    .plan-list li::before {
      content: "✓";
      color: var(--accent);
      font-weight: bold;
      margin-right: 0.5rem;
    }

    /* FAQ */
    .accordion-button {
      background: transparent;
      color: white;
      font-weight: 600;
      font-size: 1.15rem;
      border: 1px solid transparent;
      transition: 0.2s;
    }

    .accordion-button:not(.collapsed) {
      background: rgba(255,255,255,0.03);
      color: white;
      box-shadow: none;
      border-color: var(--primary);
    }

    .accordion-button:focus {
      border-color: var(--accent);
      box-shadow: 0 0 12px rgba(0,240,255,0.4);
    }

    .accordion-body {
      background: rgba(15,15,26,0.7);
      color: var(--text-body);
      line-height: 1.9;
    }

    .faq-dot {
      color: var(--primary);
      margin-right: 0.5rem;
      font-weight: bold;
    }

    /* 联系表单 */
    .form-control-dark {
      background: #2A2A3C;
      border: 1px solid #3A3A50;
      color: white;
      border-radius: 8px;
      padding: 0.8rem 1.2rem;
    }

    .form-control-dark:focus {
      background: #2A2A3C;
      border-color: var(--primary);
      box-shadow: 0 0 12px rgba(255,107,44,0.5);
      color: white;
    }

    .btn-submit {
      background: linear-gradient(135deg, #FF6B2C, #FF5722);
      border: none;
      font-weight: 700;
      padding: 1rem;
      font-size: 1.1rem;
      border-radius: 8px;
      transition: var(--transition);
    }

    .btn-submit:hover {
      filter: brightness(1.2);
      box-shadow: 0 0 24px var(--primary-glow);
    }

    .footer-link {
      color: #999;
      text-decoration: none;
      transition: 0.2s;
    }

    .footer-link:hover {
      color: var(--primary);
    }

    .social-icon {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 40px;
      height: 40px;
      border: 1px solid #555;
      border-radius: 50%;
      color: #ccc;
      margin-right: 0.5rem;
      transition: 0.25s;
    }

    .social-icon:hover {
      background: var(--primary);
      border-color: var(--primary);
      color: white;
      box-shadow: 0 0 15px var(--primary-glow);
    }

    hr {
      border-color: rgba(255,255,255,0.08);
    }