/* roulang page: index */
:root {
            --primary-navy: #0A192F;
            --primary-teal: #00B4D8;
            --primary-emerald: #10B981;
            --accent-neon: #00F5D4;
            --accent-amber: #F59E0B;
            --bg-light: #F8FAFC;
            --card-radius: 20px;
            --hero-radius: 28px;
            --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        body {
            font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-light);
            color: #1E293B;
            overflow-x: hidden;
        }

        .num-font {
            font-feature-settings: "tnum";
            font-variant-numeric: tabular-nums;
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
        }

        .card-hover-effect {
            transition: var(--transition-smooth);
        }
        .card-hover-effect:hover {
            transform: translateY(-6px);
            box-shadow: 0 20px 35px -10px rgba(0, 0, 0, 0.12);
        }

        .gradient-border-box {
            position: relative;
            background: #FFFFFF;
            border-radius: var(--card-radius);
        }
        .gradient-border-box::before {
            content: "";
            position: absolute;
            inset: -1.5px;
            border-radius: calc(var(--card-radius) + 1.5px);
            background: linear-gradient(135deg, #00B4D8, #10B981, transparent 65%);
            z-index: -1;
        }

        .mesh-grid-pattern {
            background-image: radial-gradient(rgba(0, 180, 216, 0.12) 1px, transparent 1px), radial-gradient(rgba(16, 185, 129, 0.08) 1px, transparent 1px);
            background-size: 32px 32px;
            background-position: 0 0, 16px 16px;
        }

        /* 手风琴平滑旋转箭头 */
        details[open] summary .faq-arrow {
            transform: rotate(180deg);
        }
        details summary::-webkit-details-marker {
            display: none;
        }