JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div class="main">
        <div class="header">This is the header</div>
        <div class="content">This is the content</div>
        <div class="footer">This is the footer</div>
    </div>
</body>

CSS

html, form {
            height: 100%;
        }
        body {
            padding: 0px;
            margin: 0px;
            background-image: url('../back.jpg');
            height: 100%;
        }
        .main {
            margin: 0px auto;
            width: 100%;
            height: 100%;
            position: relative;
        }
        .header {
            float: left;
            width: 100%;
            background-color: Yellow;
            height: 80px;
        }
        .content {
            width: 960px;
            margin: 0 auto;
            background-color: Gray;
            padding-bottom: 50px;
            min-height: 90%;
        }
        .footer {
            position: fixed;
            bottom: 0;
            left: 50%;
            width: 960px;
            margin-left: -480px;
            height: 50px;
            background-color: Green;
        }