JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
</head>
<body>

<div id="container">    
    <div id="main">
        Контент
    </div>   
</div>
    
<footer>
        &copy;
</footer>

</body>
</html>

CSS

html{position:relative;

    min-height:100%;
    min-width: 1000px;
    }
body{
       min-height:100%;
}

#container{
    width: 100%;
    min-height: 100%;
    }

/* Content */
#main{
    width: 100%;
    padding-bottom: 43px;
    background-color: blue;
    }

/* Footer */

body>footer{
position:absolute;bottom:0;left:0;
    width: 100%;
    height: 100px;
    background-color: red;
    }