/* roulang page: index */
:root {
            --deep-blue: #0A1628;
            --page-bg: #080F1A;
            --cyan-accent: #00E5FF;
            --orange-accent: #FF6B35;
            --text-primary: #FFFFFF;
            --text-secondary: #B0C4DE;
            --text-muted: #6B7C93;
            --card-border: rgba(255, 255, 255, 0.08);
            --card-bg: rgba(255, 255, 255, 0.03);
            --glass-bg: rgba(255, 255, 255, 0.06);
            --radius-lg: 16px;
            --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
            --transition-base: 300ms ease;
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }

        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'Noto Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
            background-color: var(--page-bg);
            color: var(--text-secondary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        a {
            text-decoration: none;
            color: inherit;
            transition: color var(--transition-base);
        }

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

        button,
        input {
            font-family: inherit;
            outline: none;
        }

        button {
            cursor: pointer;
            border: none;
            background: none;
        }

        /* 自定义滚动条 */
        ::-webkit-scrollbar {
            width: 6px;
            background: var(--page-bg);
        }
        ::-webkit-scrollbar-thumb {
            background: rgba(0, 229, 255, 0.25);
            border-radius: 10px;
        }

        .container-main {
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
            padding-left: 1.5rem;
            padding-right: 1.5rem;
        }

        /* 导航栏 */
        .nav-blur {
            background: rgba(10, 22, 40, 0.85);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid transparent;
            background-image: linear-gradient(rgba(10, 22, 40, 0.85), rgba(10, 22, 40, 0.85)), linear-gradient(90deg, var(--cyan-accent), transparent 70%);
            background-origin: border-box;
            background-clip: padding-box, border-box;
        }

        .search-box {
            background: rgba(255, 255, 255, 0.05);
            border-radius: 9999px;
            color: white;
            padding: 0.6rem 1.2rem 0.6rem 2.8rem;
            border: 1px solid transparent;
            transition: all var(--transition-base);
            width: 100%;
            font-size: 0.9rem;
        }
        .search-box::placeholder {
            color: var(--text-muted);
            font-weight: 400;
        }
        .search-box:focus {
            border-color: var(--cyan-accent);
            background: rgba(255, 255, 255, 0.08);
            box-shadow: 0 0 18px rgba(0, 229, 255, 0.3);
        }

        .nav-link {
            position: relative;
            font-weight: 500;
            color: var(--text-secondary);
            padding: 0.4rem 0;
            transition: color var(--transition-base);
            font-size: 0.95rem;
        }
        .nav-link:hover {
            color: white;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: -4px;
            left: 0;
            width: 0%;
            height: 2px;
            background: var(--cyan-accent);
            transition: width var(--transition-base);
        }
        .nav-link:hover::after {
            width: 100%;
        }

        /* 卡片通用 */
        .card-glass {
            background: var(--glass-bg);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border: 1px solid var(--card-border);
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow-card);
            transition: all var(--transition-base);
        }
        .card-glass:hover {
            border-color: rgba(0, 229, 255, 0.35);
            transform: translateY(-4px);
            box-shadow: 0 16px 40px rgba(0, 0, 0, 0.5);
        }
        .card-light {
            background: rgba(255, 255, 255, 0.02);
            border: 1px solid rgba(255, 255, 255, 0.05);
            border-radius: var(--radius-lg);
            transition: all var(--transition-base);
        }
        .card-light:hover {
            border-color: rgba(0, 229, 255, 0.25);
            background: rgba(255, 255, 255, 0.04);
        }

        .btn-primary {
            background: linear-gradient(135deg, #00E5FF, #0088CC);
            color: #0A1628;
            font-weight: 700;
            border-radius: 9999px;
            padding: 0.8rem 2rem;
            box-shadow: 0 0 20px rgba(0, 229, 255, 0.4);
            transition: all var(--transition-base);
            display: inline-flex;
            align-items: center;
            justify-content: center;
            letter-spacing: 0.3px;
        }
        .btn-primary:hover {
            box-shadow: 0 0 35px rgba(0, 229, 255, 0.7);
            transform: scale(1.03);
        }
        .btn-outline {
            border: 1px solid rgba(0, 229, 255, 0.6);
            color: var(--cyan-accent);
            font-weight: 600;
            border-radius: 9999px;
            padding: 0.75rem 2rem;
            transition: all var(--transition-base);
            display: inline-flex;
            align-items: center;
            justify-content: center;
        }
        .btn-outline:hover {
            background: rgba(0, 229, 255, 0.1);
            border-color: var(--cyan-accent);
        }

        .tab-active {
            border-left: 3px solid var(--cyan-accent);
            background: rgba(0, 229, 255, 0.08);
            color: white;
            font-weight: 600;
        }

        .counter-digit {
            font-variant-numeric: tabular-nums;
            font-weight: 700;
            color: var(--cyan-accent);
        }

        /* FAQ 手风琴 */
        .faq-item {
            border: 1px solid rgba(255, 255, 255, 0.06);
            border-radius: 12px;
            background: rgba(255, 255, 255, 0.02);
            transition: border var(--transition-base);
            overflow: hidden;
        }
        .faq-item.active {
            border-color: var(--cyan-accent);
        }
        .faq-question {
            cursor: pointer;
            padding: 1.2rem 1.5rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-weight: 600;
            color: white;
        }
        .faq-icon {
            transition: transform 0.3s ease;
            color: var(--cyan-accent);
            font-size: 1.3rem;
        }
        .faq-item.active .faq-icon {
            transform: rotate(45deg);
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease;
            background: rgba(0, 0, 0, 0.2);
            color: var(--text-secondary);
            padding: 0 1.5rem;
        }
        .faq-item.active .faq-answer {
            max-height: 200px;
            padding: 1rem 1.5rem;
        }

        @media (max-width: 1024px) {
            .desktop-only {
                display: none;
            }
        }
        @media (max-width: 768px) {
            .hero-layout {
                flex-direction: column;
                text-align: center;
            }
            .hero-text h1 {
                font-size: 2rem;
            }
            .grid-cols-4-sm {
                grid-template-columns: 1fr;
            }
            .faq-grid {
                grid-template-columns: 1fr;
            }
            .footer-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .nav-search-wrap {
                order: 3;
                width: 100%;
                margin-top: 0.8rem;
            }
        }
        @media (min-width: 769px) {
            .mobile-menu-btn {
                display: none;
            }
        }