/* roulang page: index */
:root {
            --primary-blue: #1e40af;
            --secondary-cyan: #0284c7;
            --accent-sky: #0ea5e9;
            --bg-light: #f8fafc;
            --text-heading: #0f172a;
            --text-body: #334155;
            --text-muted: #64748b;
            --border-color: #e2e8f0;
            --card-radius: 1rem;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-light);
            color: var(--text-body);
            line-height: 1.65;
            -webkit-font-smoothing: antialiased;
        }

        /* 轮播组件状态控制 */
        .hero-slide {
            display: none;
            opacity: 0;
            transition: opacity 0.6s ease-in-out;
        }
        .hero-slide.active {
            display: block;
            opacity: 1;
        }

        /* 手风琴状态过渡 */
        .accordion-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out;
        }
        .accordion-content.expanded {
            max-height: 480px;
        }
        .accordion-icon {
            transition: transform 0.3s ease;
        }
        .accordion-header.active .accordion-icon {
            transform: rotate(180deg);
        }

        /* 交互微动效 */
        .card-elevated {
            transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-elevated:hover {
            transform: translateY(-4px);
            box-shadow: 0 16px 32px -8px rgba(15, 23, 42, 0.12);
        }