/* roulang page: index */
:root {
            --primary: #1E3A8A;
            --primary-accent: #1D4ED8;
            --secondary-green: #059669;
            --warning-amber: #D97706;
            --bg-light: #F8FAFC;
            --text-dark: #0F172A;
            --text-body: #334155;
            --text-muted: #64748B;
            --border-light: #E2E8F0;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
            color: var(--text-body);
            background-color: #FFFFFF;
            line-height: 1.75;
            overflow-x: hidden;
        }
        .text-balance {
            text-wrap: balance;
        }
        .glass-nav {
            background-color: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
        }
        .hero-overlay {
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.88) 0%, rgba(30, 58, 138, 0.82) 100%);
        }
        .badge-sub {
            display: inline-flex;
            align-items: center;
            gap: 0.375rem;
            padding: 0.25rem 0.75rem;
            border-radius: 9999px;
            font-size: 0.8125rem;
            font-weight: 600;
            letter-spacing: 0.05em;
        }
        .card-hover-effect {
            transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.25s ease;
        }
        .card-hover-effect:hover {
            transform: translateY(-4px);
            box-shadow: 0 20px 25px -5px rgba(15, 23, 42, 0.08), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
            border-color: #93C5FD;
        }
        .faq-item-content {
            transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
            overflow: hidden;
        }
        .faq-item-content.collapsed {
            max-height: 0;
        }
        .faq-item-content.expanded {
            max-height: 500px;
            transition: max-height 0.4s ease-in-out;
        }