JSFiddle - React, Tailwind, and code Playground

HTML

<!doctype html>
<html lang="de">
    <head>
        <meta charset="UTF-8" />
        <title>green box, orange borders</title>
    </head>
    <body>
        
        <div>
            <div>
                Very long content, very long content, very long content, very long content, very long content,
                very long content, very long content, very long content, very long content, very long content!<br />
                Content<br />Content<br />Content<br />Content<br />Content<br />
                Content<br />Content<br />Content<br />Content<br />Content<br />
                Content<br />Content<br />Content<br />Content<br />Content<br />
                Content<br />Content<br />Content<br />Content<br />Content<br />
                Content<br />Content<br />Content<br />Content<br />Content<br />
            </div>
        </div>
        
    </body>
</html>

CSS

@charset "UTF-8";

/* common */
* {
    margin: 0 ;
    padding: 0 ;
    border: 0 none ;
}

html, body {
    width: 100% ;
    height: 100% ;
}

/* green box, orange borders */
body > div {
    position: absolute ;
    margin: -200px 0 0 -350px ;
    top: 50% ;
    left: 50% ;
    width: 700px ;
    height: 400px ;
    background-color: lightgreen ;
}

body > div::before,
body > div::after {
    position: absolute ;
    content: "" ;
    /*z-index: -1 ;*/
}

body > div::before {
    margin: -30px 0 0 -150px ;
    left: 50% ;
    width: 300px ;
    height: 430px ;
    border-top: 15px solid orange ;
    border-bottom: 15px solid orange ;
    
    /* demonstration */
    border-left: 1px dotted grey ;
    border-right: 1px dotted grey ;
}

body > div::after {
    margin: -100px 0 0 -30px ;
    top: 50% ;
    width: 730px ;
    height: 200px ;
    border-left: 15px solid orange ;
    border-right: 15px solid orange ;
    
    /* demonstration */
    border-top: 1px dotted grey ;
    border-bottom: 1px dotted grey ;
}

/* content */
div > div {
    width: 700px ;
    height: 400px ;
    overflow: auto ;
}

div > div:hover {
    background-color: lightblue ;
}