JSFiddle - React, Tailwind, and code Playground

HTML

<h2><span>Das ist eine h2 Überschrift</span><span>über 2 Zeilen</span></h2>

CSS

h2 {
    border-radius: 10px 0 10px 0;
    background-color: #f00;
    display: inline;
}

h2 span {
    white-space: pre;
}

h2 span:first-child:before {
    content:"";
    padding-left: 10px;
}

h2 span:first-child:after {
    content:"\A";
    padding-right: 10px;
}

h2 span:last-child:before {
    content:"";
    padding-left: 10px;
}

h2 span:last-child:after {
    content:"";
    padding-right: 10px;
}