JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li>Первый
    </li><li>Второй
    </li><li>Третий</li>
</ul>

CSS

ul {
    margin: 0;
    padding: 4px;
    background: linear-gradient(#999, #555);
}
li {
    display: inline-block;
    padding: 5px 12px 5px 10px;
    box-shadow: inset -1px 0 0 0 #444, inset -2px 0 0 0 #aaa;
}
li:last-child {
    box-shadow: none;
}