老师，帮我看一下，我的点击怎么没有效果

来源：3-4 行为层

慕村0048207

2019-04-11 18:11:00

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>全屏的旅游相册</title>
<link rel="stylesheet" href="css/style.css">
<script type="text/javascript" src="https://code.jquery.com/jquery-1.12.4.js"></script>
<script type="text/javascript" src="js/script.js"></script>
</head>
<body>
<span></span>
<nav>
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</nav>
<div>
  <img src="images/1.jpg">
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  <img src="images/3.jpg">
  <img src="images/4.jpg">
  <img src="images/5.jpg">
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  <img src="images/11.jpg">
  <img src="images/12.jpg">
</div>
</body>
</html>

*{
padding:0;
margin:0;
border:none;
}
html,body{
overflow:hidden;
height:100%;
background:#93b3c6;

}
span{
display:block;
width:16px;
height:16px;
margin:30px auto 40px;
border-radius: 50%;
background:#fff;
}
nav{
position:relative;
display:flex;
width:78.125vw;
margin:0 auto 45px;
justify-content:space-between;
}
nav:before{
position:absolute;
top:20px;
width:100%;
height:10px;
background:#fff;
display:block;
content:"";

}
nav>a{
position:relative;
font-size:16px;
padding:10px;
border:2px solid #5395b4;
color:#255d7e;
text-decoration:none;
background:#fff;

}
div{
position:relative;
overflow:hidden;
width:78.125vw;
height:75vh;
margin:0 auto;
background:#fff;
box-shadow:0 0 30px 0 rgba(8,1,3,0.3);
}
div>img{
position:absolute;
top:0;
right:0;
bottom:0;
left:0;
margin:auto;
width:98%;
height:96%;