元素，只要把六个
div叠在一起，搭配CSS的
animation，就可以让六个
div依序出现。
代码示例
.wave0{
z-index:2;
background-size:auto 106%;
animation:w 1s forwards;
}
.wave1{
z-index:3;
background-size:auto 102%;
animation:w 1s .2s forwards;
}
.wave2{
z-index:4;
background-size:auto 104%;
animation:w 1s .4s forwards;
}
.wave3{
z-index:5;
background-size:auto 101%;
animation:w 1s .5s forwards;
}
.wave4{
z-index:6;
background-size:auto 102%;
animation:w 1s .8s forwards;
}
.wave5{
z-index:7;
background-size:auto 100%;
animation:w 1s 1s forwards;
}4、通过@keyframes规则，创建动画是通过逐步改变0％是开头动画，100％是当动画完成，注意: 使用animation属性来控制动画的外观，还使用选择器绑定动画。
@keyframes w{
0%{
top:calc((100% - 30px)/2);
left:calc((100% - 30px)/2);
width:30px;
height:30px;
}
100%{
top:calc((100% - 300px)/2);
left:calc((100% - 300px)/2);
width:300px;
height:300px;
}ok,代码完成
完整代码
.wave{
position:absolute;
top:calc((100% - 30px)/2);
left:calc((100% - 30px)/2);
width:30px;
height:30px;
border-radius:300px;
background:url(dsd.jpg);
background-attachment:fixed;
background-position:center center;
}
.wave0{
z-index:2;
background-size:auto 106%;
animation:w 1s forwards;
}
.wave1{
z-index:3;
background-size:auto 102%;
animation:w 1s .2s forwards;
}
.wave2{
z-index:4;
background-size:auto 104%;
animation:w 1s .4s forwards;
}
.wave3{
z-index:5;
background-size:auto 101%;
animation:w 1s .5s forwards;
}
.wave4{
z-index:6;
background-size:auto 102%;
animation:w 1s .8s forwards;
}
.wave5{
z-index:7;
background-size:auto 100%;
animation:w 1s 1s forwards;
}
@keyframes w{
0%{
top:calc((100% - 30px)/2);
left:calc((100% - 30px)/2);
width:30px;
height:30px;
}
100%{
top:calc((100% - 300px)/2);
left:calc((100% - 300px)/2);
width:300px;
height:300px;
}
}
