/* roulang page: index */
:root {
            --primary: #0F172A;
            --primary-accent: #0D9488;
            --highlight: #14B8A6;
            --bg-light: #F8FAFC;
            --text-main: #1E293B;
            --text-muted: #475569;
            --border-line: #E2E8F0;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
            color: var(--text-main);
            background-color: #FFFFFF;
            overflow-x: hidden;
        }
        .hero-mesh {
            background-image: radial-gradient(rgba(13, 148, 136, 0.12) 1px, transparent 1px), radial-gradient(rgba(15, 23, 42, 0.08) 1px, transparent 1px);
            background-size: 28px 28px;
            background-position: 0 0, 14px 14px;
        }
        .dark-grid-bg {
            background-image: linear-gradient(to right, rgba(255, 255, 255, 0.05) 1px, transparent 1px),
                              linear-gradient(to bottom, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
            background-size: 32px 32px;
        }
        .glass-nav {
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
        }
        .card-shadow {
            box-shadow: 0 10px 30px -10px rgba(15, 23, 42, 0.08);
        }
        .card-shadow-hover:hover {
            box-shadow: 0 20px 35px -10px rgba(13, 148, 136, 0.18);
            transform: translateY(-4px);
        }
        .accordion-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .accordion-item.active .accordion-content {
            max-height: 240px;
        }
        .accordion-item.active .accordion-icon {
            transform: rotate(180deg);
        }