/* roulang page: index */
:root {
            --bg-base: #0B0F19;
            --bg-card: #141A29;
            --color-primary: #6366F1;
            --color-secondary: #8B5CF6;
            --color-accent: #10B981;
            --border-glass: rgba(255, 255, 255, 0.08);
            --border-glow: rgba(99, 102, 241, 0.3);
        }
        body {
            background-color: var(--bg-base);
            color: #94A3B8;
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            overflow-x: hidden;
        }
        .text-gradient {
            background: linear-gradient(135deg, #F8FAFC 20%, #A5B4FC 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .text-gradient-purple {
            background: linear-gradient(135deg, #818CF8 0%, #C084FC 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .glass-panel {
            background-color: var(--bg-card);
            border: 1px solid var(--border-glass);
            box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.5);
            transition: all 300ms cubic-bezier(0.16, 1, 0.3, 1);
        }
        .glass-panel:hover {
            transform: translateY(-4px);
            border-color: var(--border-glow);
            box-shadow: 0 25px 50px -12px rgba(99, 102, 241, 0.15);
        }
        .accordion-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out;
        }
        .accordion-content.open {
            max-height: 500px;
        }
        .chevron-icon {
            transition: transform 0.3s ease;
        }
        .rotate-icon {
            transform: rotate(180deg);
        }