/* roulang page: index */
:root {
            --primary: #1B2A32;
            --accent: #F26419;
            --accent-gold: #E5A93C;
            --bg-surface: #F7F9FA;
            --bg-dark: #0F171C;
            --text-main: #334155;
            --text-muted: #64748B;
            --border-color: #E2E8F0;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
            color: var(--text-main);
            background-color: #FFFFFF;
            line-height: 1.75;
        }
        .mono-num {
            font-family: "DIN Alternate", -apple-system, monospace;
            font-feature-settings: "tnum";
        }
        .hero-bg {
            background-image: linear-gradient(rgba(15, 23, 28, 0.78), rgba(15, 23, 28, 0.88)), url('/assets/images/8457bcc5718b8624.webp');
            background-size: cover;
            background-position: center;
        }
        .dark-showcase-bg {
            background-image: linear-gradient(rgba(15, 23, 28, 0.92), rgba(15, 23, 28, 0.94)), url('/assets/images/c7dbda890d03a82d.webp');
            background-size: cover;
            background-position: center;
        }
        .accordion-content {
            transition: max-height 0.3s ease-out;
        }
        details[open] summary svg {
            transform: rotate(180deg);
        }
        summary::-webkit-details-marker {
            display: none;
        }
        .sticky-bar-visible {
            transform: translateY(0);
            opacity: 1;
        }
        .sticky-bar-hidden {
            transform: translateY(100%);
            opacity: 0;
        }