JSFiddle - React, Tailwind, and code Playground

HTML

<main>
<div id="topic_left">
<h2>Veranstaltungen</h2>
</div>
</main>

CSS

main {
  position:relative;
  width: 300px; height: 300px;
  background-color: #fcc
}
#topic_left {
  position: absolute;
  left:20px;   top:18px;   width:106px;   height:250px;
  z-index:5; background-color: #ccf;
	display: flex; align-items:center;justify-content:center;
}

h2 
{
	font: bold 18px arizona, arial, verdana;
	transform: rotate(-90deg);
	color: #670000;
}