content字符生成配合CSS3 animation的点点点loading效果实例代码：CSS代码：dot {    display: inline-block;     height: 1em; line-height: 1;    vertical-align: -.25em;    overflow: hidden;}dot::before {    display: block;    content: '...\A..\A.';    white-space: pre-wrap;    animation: dot 3s infinite step-start both;}@keyframes dot {    33% { transform: translateY(-2em); }    66% { transform: translateY(-1em); }}HTML代码：订单提交中
      
       ...
      效果：订单提交中...Designed & Powerd by zhangxinxu 更多demo：更多加载地址：http://tawian.io/text-spinners/