预加载优化 */
        .slide-frame.preloading {
            visibility: hidden;
            position: absolute;
            top: -9999px;
            left: -9999px;
        }

        /* 响应式设计 */
        @media (max-width: 768px) {
            .slide-display {
                width: 95vw;
                height: 95vh;
            }

            .presentation-controls {
                bottom: 15px;
                padding: 10px 15px;
                gap: 10px;
            }

            .cont