/* roulang page: index */
:root {
            --primary: #1E40AF;
            --accent: #0EA5E9;
            --cta: #F97316;
            --bg-main: #F8FAFC;
            --text-title: #0F172A;
            --text-body: #334155;
            --text-muted: #64748B;
            --border-color: #E2E8F0;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: var(--bg-main);
            color: var(--text-body);
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            -webkit-font-smoothing: antialiased;
        }
        .container-custom {
            max-width: 1200px;
            margin-left: auto;
            margin-right: auto;
            padding-left: 1.25rem;
            padding-right: 1.25rem;
        }
        .card-shadow {
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-shadow:hover {
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
            transform: translateY(-4px);
        }
        .btn-hover-effect {
            transition: all 0.25s ease;
        }
        .btn-hover-effect:hover {
            transform: translateY(-2px);
            filter: brightness(1.05);
        }
        .btn-hover-effect:active {
            transform: translateY(0);
        }
        .faq-content {
            transition: max-height 0.3s ease-out, opacity 0.3s ease-out;
            max-height: 0;
            overflow: hidden;
            opacity: 0;
        }
        .faq-content.open {
            max-height: 260px;
            opacity: 1;
        }
        .hero-slide {
            transition: opacity 0.8s ease-in-out;
        }