/* roulang page: index */
:root {
            --primary: #0E7490;
            --primary-hover: #155E75;
            --accent: #059669;
            --obsidian: #090D16;
            --card-border: #E2E8F0;
            --text-title: #0F172A;
            --text-body: #475569;
            --bg-light: #F8FAFC;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            color: var(--text-body);
            background-color: #FFFFFF;
            overflow-x: hidden;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            line-height: 1.75;
        }

        /* 标题间距与平滑渲染 */
        h1, h2, h3, h4, h5, h6 {
            color: var(--text-title);
            letter-spacing: -0.02em;
            font-weight: 700;
        }

        /* 微交互质感组件 */
        .glass-nav {
            background: rgba(255, 255, 255, 0.94);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
        }

        .shadow-soft {
            box-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05), 0 2px 6px -1px rgba(15, 23, 42, 0.03);
        }

        .shadow-hover {
            transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
        }
        .shadow-hover:hover {
            transform: translateY(-3px);
            box-shadow: 0 12px 28px -4px rgba(14, 116, 144, 0.12), 0 4px 10px -2px rgba(15, 23, 42, 0.04);
            border-color: #0E7490;
        }

        /* 轮播指示器 */
        .slide-item {
            opacity: 0;
            transition: opacity 0.8s ease-in-out;
            pointer-events: none;
        }
        .slide-item.active {
            opacity: 1;
            pointer-events: auto;
        }

        /* 移动端菜单抽屉 */
        #mobile-menu-drawer {
            transform: translateX(100%);
            transition: transform 0.3s ease-in-out;
        }
        #mobile-menu-drawer.open {
            transform: translateX(0);
        }

        /* 细节装饰细线 */
        .grid-tech-pattern {
            background-size: 40px 40px;
            background-image: 
                linear-gradient(to right, rgba(255, 255, 255, 0.04) 1px, transparent 1px),
                linear-gradient(to bottom, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
        }