JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" value="This is read only part" id="first" readonly="readonly" />
<input type="text" value="Editable" id="second" />

CSS

#first {
    border-right: none;
}

#second {
    border-left: none;
    margin-left: -5px;
}