/* roulang page: index */
:root {
            --primary: #1d4ed8;
            --primary-light: #3b82f6;
            --accent: #0891b2;
            --bg-base: #f8fafc;
            --surface: #ffffff;
            --text-main: #0f172a;
            --text-muted: #64748b;
            --border-color: #e2e8f0;
            --shadow-card: 0 10px 25px -5px rgba(15, 23, 42, 0.05), 0 8px 10px -6px rgba(15, 23, 42, 0.05);
            --shadow-hover: 0 20px 30px -10px rgba(29, 78, 216, 0.12), 0 10px 15px -5px rgba(15, 23, 42, 0.08);
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-base);
            color: var(--text-main);
            overflow-x: hidden;
            line-height: 1.6;
        }

        .custom-card {
            background-color: var(--surface);
            border: 1px solid var(--border-color);
            border-radius: 1rem;
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            box-shadow: var(--shadow-card);
        }

        .custom-card:hover {
            transform: translateY(-4px);
            border-color: #cbd5e1;
            box-shadow: var(--shadow-hover);
        }

        .glow-effect {
            position: relative;
        }
        .glow-effect::after {
            content: '';
            position: absolute;
            top: 0; left: 0; right: 0; bottom: 0;
            border-radius: inherit;
            box-shadow: inset 0 0 20px rgba(8, 145, 178, 0.15);
            pointer-events: none;
        }

        .tab-btn.active {
            background-color: #1d4ed8;
            color: #ffffff;
            border-color: #1d4ed8;
        }

        .accordion-content {
            transition: max-height 0.35s ease-out, opacity 0.3s ease;
            max-height: 0;
            overflow: hidden;
            opacity: 0;
        }

        .accordion-content.open {
            max-height: 500px;
            opacity: 1;
        }

        .rotate-chevron {
            transition: transform 0.3s ease;
        }
        .rotate-chevron.open {
            transform: rotate(180deg);
        }