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HTML 

              
                <html>
    <head>
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>
            Creating three column responsive layout
        </title>
        <link rel="stylesheet" href="./css/style.css">
    </head>

    <body>
        <header>
            <h1>Three column responsive layout</h1>         
        </header>
           
           <main>
               <div class="col col1">
                   <h2>Column 1</h2>
                   <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Aperiam fugiat eveniet doloribus veritatis nisi quibusdam quasi neque delectus et, quod sed quas ea quaerat distinctio corporis quo non necessitatibus illum accusamus. Velit deleniti sit neque ipsam quo, natus enim laborum earum tenetur atque in corrupti perferendis fugiat dicta vel qui. Recusandae, pariatur perspiciatis? Libero delectus sed, nesciunt assumenda maiores nostrum praesentium mollitia quisquam ut magni illo quo veniam dolor atque culpa suscipit, rem minima repudiandae soluta reiciendis voluptatibus officiis. Dicta dolore, ab qui laudantium unde veritatis quidem ipsa possimus harum reiciendis facilis atque a. Doloremque harum ab, odio nostrum atque.
               </div>
               <div class="col col2">
                   <h2>Column 2</h2>
                 <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Atque voluptas excepturi illo cum mollitia, earum libero asperiores. Fugit deserunt, dolorem vero, commodi adipisci voluptatum. At impedit repellat tempore ratione quo sequi. Dicta ex distinctio nulla cumque, quod illum, quisquam ullam voluptate! Non quas consectetur tempore doloremque. Blanditiis vel beatae laudantium molestias quibusdam id, ullam consectetur est asperiores officia dolorem, tempora unde eum. Veniam ad aliquam tempora, repellendus dolor vitae ipsa voluptatum quam qui mollitia voluptas numquam, eaque assumenda, autem, ipsum velit provident veritatis magni iste recusandae fuga. Vero ullam, qui nemo maiores repudiandae, voluptatum obcaecati consequatur illo, voluptates quod facere aut eveniet ex autem nisi, non odit corporis expedita magnam sunt eaque atque. Laborum dicta impedit, repellendus delectus placeat velit praesentium tenetur doloribus, obcaecati et ullam consequatur, a. Rem, voluptatem eius asperiores porro maxime at, illum id corporis a pariatur quasi odit labore quis, aperiam eos eligendi, temporibus expedita? Atque in, quae doloribus maiores dolorem ipsam mollitia quam magnam delectus praesentium sit quidem est facilis, porro officiis hic fugit repellat enim pariatur dignissimos. Eaque, tenetur consequatur. Voluptatum ipsum asperiores at autem nisi ipsam, aliquam possimus, nam, sunt illum repellat. Quo minus maxime enim totam et laudantium iusto odit dolor perferendis!</p>
               </div>
               <div class="col col3">
                   <h2>Column 3</h2>
                 <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Similique modi a consequatur voluptate, quod quasi veniam magni esse labore illum, unde magnam quos. Accusamus at amet obcaecati eligendi magnam eveniet, optio repellat quia voluptate architecto numquam voluptas maxime quasi esse.
               </div>
           </main>
       
        <footer>
            &copy; 2015 | Smashtheshell
        </footer>
    </body>
</html>
!

CSS 

              
                body,html,h1,h2,p, div,a,img,header,footer,span{
    margin: 0;
    padding: 0;
}
*{box-sizing:border-box}
html{background:#343434;}
footer,header{background: #00b4de; color: #fbfbfb; font-family: Arial, "Helvetica Neue", Helvetica, sans-serif; text-align: center; padding: 2em 0;}

main{
  width:94.75%;
margin: 0 auto;
 overflow: hidden;
}

.col{
    width: 33.333%;
    height:500px;
    float: left;
    text-align: center;
    padding:1rem;
}
.col1{ background: #9bd5ff;}
.col2{ background: #ffd587;}
.col3{ background: #ff8787;}

footer{
    clear:both;
}

@media only screen and (max-width:768px){
    
    .col1, .col2{
        width:50%;
    }
    .col3{
        width:100%;
    }
}

@media only screen and (max-width:480px){
    .col{
       float: none;
        width:100%;
    }
}
!

JS
!
999px

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