html--鱼群
<!DOCTYPE html>
<html lang="en" >
<head>
<meta charset="UTF-8">
<title>Only CSS: Swimming Fish</title>
<link rel="stylesheet" href="css/style.css">
</head>
<body>
<div class="container">
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class="trigger"></div>
<div class=