代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>心跳</title>
<!--html标签默认width：885px;height:500px
body标签默认 885px;height:500px-->
<style>
html,body {
height: 100%; /*885px;height:740px*/
/*background-color: red;*/
}
body {
margin:0;
padding:0;
background: #ffa5a5;/*淡粉色*/
background: linear-gradient(to bottom,#ffa5a5 0%,#ffd3d3 100%);
}
.chest {
500px;
height: 500px;
margin: 0 auto;/*水平居中，那垂直居中呢？*/
position: relative;
}
.heart {
position: absolute;
z-index: 2;
/*linear-gradient(direction, color-stop1, color-stop2, ...);*/
background: linear-gradient(-90deg,#f50a45 0%,#d5093c 40%);
animation: beat 0.7s ease 0s infinite normal;
}
.heart.center {
background: linear-gradient(-45deg,#b80734 0%,#d5093c 40%);
}
.heart.top {
z-index: 3;
}
.side {
220px;
height: 220px;
top: 100px;
border-radius: 220px;
}
.center {
210px;
height: 210px;
bottom: 100px;
left: 145px;
}
.left {
left: 62px;
}
.right {
right: 62px;
}
@keyframes beat {
0% {
transform: scale(1) rotate(225deg);
box-shadow: 0 0 40px #d5093c;
}
50% {
transform: scale(1.1) rotate(225deg);
box-shadow: 0 0 70px #d5093c;
}
100% {
transform: scale(1) rotate(225deg);
box-shadow: 0 0 40px #d5093c;
}
}
</style>
</head>
<body>
<div class="chest">
<div class="heart left side top"></div>
<div class="heart center"></div>
<div class="heart right side"></div>
</div>
</body>
</html>
显示：
