/* roulang page: index */
:root {
            --primary-dark: #0F172A;
            --primary-accent: #0EA5E9;
            --bg-light: #F8FAFC;
            --text-main: #334155;
            --text-muted: #64748B;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: var(--bg-light);
            color: var(--text-main);
            font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", sans-serif;
            line-height: 1.65;
            -webkit-font-smoothing: antialiased;
        }
        .hero-bg {
            background-image: linear-gradient(to right, rgba(15, 23, 42, 0.95), rgba(15, 23, 42, 0.75)), url('/assets/images/0be5af713692713e.webp');
            background-size: cover;
            background-position: center;
        }
        .tech-bg {
            background-image: linear-gradient(180deg, #0B0F19 0%, #111827 100%);
        }
        .card-hover {
            transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-hover:hover {
            transform: translateY(-4px);
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
        }
        details > summary {
            list-style: none;
        }
        details > summary::-webkit-details-marker {
            display: none;
        }
        details[open] .faq-icon {
            transform: rotate(180deg);
        }