<!DOCTYPE html>
<html style="-webkit-writing-mode: vertical-rl;">
    <head>
        <style>
            div {
                position: absolute;
                width: 100px;
                height: 100px;
                border: 3px solid black;
                left: 0;
                right: 0;
            }
        </style>
    </head>
    <body>
        <div></div>
    </body>
</html>