FCC---Animate Elements Continually Using an Infinite Animation Count---设置animation-iteration-count的次数为无限，让小球一直跳动

The previous challenges covered how to use some of the animation properties and the @keyframes rule.

Another animation property is the animation-iteration-count, which allows you to control how many times you would like to loop through the animation.

Here's an example:

animation-iteration-count: 3;

In this case the animation will stop after running 3 times, but it's possible to make the animation run continuously by setting that value to infinite.

把次数改为无线infinite就一直动。

练习题目：

To keep the ball bouncing on the right on a continuous loop, change the animation-iteration-count property to infinite.

练习代码： （不需要全部写，填空进去）

 <style>
 
   #ball {
     width: 100px;
     height: 100px;
     margin: 50px auto;
     position: relative;
     border-radius: 50%;
     background: linear-gradient(
       35deg,
       #ccffff,
       #ffcccc
     );
     animation-name: bounce;
     animation-duration: 1s;
     animation-iteration-count: infinite;
   }
 
   @keyframes bounce{
     0% {
       top: 0px;
     }
     50% {
       top: 249px;
       width: 130px;
       height: 70px;
     }
     100% {
       top: 0px;
     }
   }
 </style>
 <div id="ball"></div>

效果：

在设置区域内，带一个好看背景色的小球，上下弹动，小球的大小会挤压又恢复，通过@keyframe设置的0%-100%的值实现的