JSFiddle - React, Tailwind, and code Playground

HTML

<antti>
      Terve
</antti>
<laaksonen>
        Maailma
</laaksonen>

CSS

antti {
    background-color:red;
    color:white;
    width:100%;
    display:inline-block;
    padding:20px;
    text-align:center;
}
laaksonen {
    background-color:blue;
    color:white;
    width:100%;
    display:inline-block;
    padding:20px;
    text-align:center;
}