/* roulang page: index */
:root {
            --color-primary: #6366F1;
            --color-cyan: #06B6D4;
            --color-emerald: #10B981;
            --color-bg-deep: #0B0F19;
            --color-bg-card: #111827;
            --color-bg-surface: #1F2937;
            --color-text-main: #F9FAFB;
            --color-text-muted: #9CA3AF;
            --border-light: rgba(255, 255, 255, 0.08);
            --border-glow: rgba(99, 102, 241, 0.4);
            --transition-smooth: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
        }

        body {
            background-color: var(--color-bg-deep);
            color: var(--color-text-main);
            overflow-x: hidden;
            font-feature-settings: "cv02", "cv03", "cv04", "cv11";
        }

        .custom-card {
            background-color: var(--color-bg-card);
            border: 1px solid var(--border-light);
            transition: var(--transition-smooth);
        }

        .custom-card:hover {
            transform: translateY(-4px);
            border-color: var(--border-glow);
            box-shadow: 0 12px 30px -10px rgba(99, 102, 241, 0.25);
        }

        .glow-tag {
            background: linear-gradient(135deg, rgba(99, 102, 241, 0.15) 0%, rgba(6, 182, 212, 0.15) 100%);
            border: 1px solid rgba(6, 182, 212, 0.3);
        }

        .bg-mesh-pattern {
            background-image: radial-gradient(rgba(99, 102, 241, 0.08) 1px, transparent 1px);
            background-size: 24px 24px;
        }

        .gradient-text {
            background: linear-gradient(135deg, #F9FAFB 20%, #A5B4FC 60%, #38BDF8 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .nav-item-active {
            color: #38BDF8 !important;
            border-bottom: 2px solid #38BDF8;
        }

        /* 手风琴平滑展开与旋转 */
        .faq-content {
            transition: max-height 0.35s ease-out, opacity 0.3s ease-out;
            max-height: 0;
            opacity: 0;
            overflow: hidden;
        }
        .faq-item.active .faq-content {
            max-height: 200px;
            opacity: 1;
        }
        .faq-item.active .faq-arrow {
            transform: rotate(180deg);
        }