<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta charset="utf-8"/>
<link href="./img/favicon.ico" rel="shortcut icon">
<link rel="stylesheet" href="./css/bootstrap.css">
<link rel="stylesheet" href="./css/style.css">
<script type="text/javascript" src="./js/jquery-1.11.1.min.js"></script>
<script type="text/javascript" src="./js/bootstrap.min.js"></script>
</head>
<body>
<main>
<section class="main-sec">
<header class="span2 logo" ><a><img class="logo" src="./img/DGlog-logo.png" alt="header-logo"></a></header>
<article style="clear: both"></article>
<section class="part-sec">
<article class="span4 part-container"><a><img class="dg-part" src="img/01.png" alt="pic01"></a></article>
<article class="span4 part-container"><a><img class="dg-part" src="img/02.png" alt="pic02"></a></article>
<article class="span4 part-container"><a><img class="dg-part" src="img/03.png" alt="pic03"></a></article>
<article class="span4 part-container"><a><img class="dg-part" src="img/04.png" alt="pic04"></a></article>
<article class="span4 part-container"><a><img class="dg-part" src="img/05.png" alt="pic05"></a></article>
<article class="span4 part-container"><a><img class="dg-part" src="img/06.png" alt="pic06"></a></article>
</section>
<article style="clear: both"></article>
<article class="btn-container"><button class="btn-try">Try it !</button></article>
</section>
</main>
</body>

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.dg-part{
filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
}
.dg-part:hover{
filter: none;
}
.part-container{
margin-bottom: 3%;
}
body{
background-image: url("../img/Pattern.jpg");
background-repeat: repeat-x repeat-y;
}
.main-sec{
width: 90%;
display: block;
margin: auto;
}
.logo{
display: block;
margin: auto;
float: none;
}
.part-sec{
width:80%;margin: auto;
}
.btn-container{
width:86.5%;margin: auto;
}
.btn-try{
width: 90%;display:block;
margin:auto;
border: none;
height:60px;
color: #fff;
background-color: #79c652;
font-size: 3vw;
}

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کدا رو من ننوشتم من فقط میخوام این قابلیتو بهش اضافه کنم ممنون میشم راهنمایی کنیدیه فایل bootstrap.css هم داره