<html><head><style> #myDIV { background-color: lightblue; border: 1px solid black; animation: mymove 5s infinite;}@keyframes mymove { 50% {padding-left: 50px;}}</style></head><body><h1>padding-left 的动画效果：</h1><p>逐渐将 padding-left 从 0px 改为 50px，然后再改回 0px：<p><div id="myDIV">Shanghai is one of the four direct-administered municipalities of the People's Republic of China. Welcome to Shanghai!...</div><p><b>注释：</b>CSS 动画在 Internet Explorer 9 以及更早版本中不起作用。</p></body></html>