纯CSS加载动画效果

动画加载代码：

<div class="loading-spinner"></div>
        .loading-spinner {
            width: 50px;
            height: 50px;
            border: 5px solid #f3f3f3;
            border-top: 5px solid #1890ff;
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }