Instead of using a simple 404 page, use a beautiful and humorous 404 page to both attract more users and keep a positive view of your site in the minds of users. Like this code, which is a humorous animation of a caveman who gets electrocuted because of his ignorance.


HTML
<!-- This script got from www.devanswer.com -->
<head>
<link rel='stylesheet' href='https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.min.css'>
<link rel='stylesheet' href='https://fonts.googleapis.com/css?family=Arvo'>
</head>
<section class="page_404">
        <div class="container">
                <div class="row">        
                <div class="col-sm-12 ">
                <div class="col-sm-10 col-sm-offset-1  text-center">
                <div class="four_zero_four_bg">
                        <h1 class="text-center ">404</h1>
                </div>                
                <div class="contant_box_404">
                <h3 class="h2">
                Look like you're lost
                </h3>                
                <p>the page you are looking for not avaible!</p>                
                <a href="" class="link_404">Go to Home</a>
        </div>
                </div>
                </div>
                </div>
        </div>
</section><div id="bcl"><a style="font-size:8pt;text-decoration:none;" href="http://www.devanswer.com">Developers Answer</a></div>
                        

CSS
.page_404 {
    padding: 40px 0;
    background: #fff;
    font-family: 'Arvo', serif;
}

    .page_404 img {
        width: 100%;
    }

.four_zero_four_bg {
    background-image: url(http://devanswer.com/codes/files/dribbble_electricity.gif);
    height: 400px;
    background-position: center;
}


    .four_zero_four_bg h1 {
        font-size: 80px;
    }

    .four_zero_four_bg h3 {
        font-size: 80px;
    }

.link_404 {
    color: #fff !important;
    padding: 10px 20px;
    background: #39ac31;
    margin: 20px 0;
    display: inline-block;
}

.contant_box_404 {
    margin-top: -50px;
}