JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="videos">
    <li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
</ul>

CSS

ul.videos {
    width: 100%;
    list-style: none;
    border: 1px solid green;
    margin: 0;
    padding: 0;
}
li {
    display: inline-block;
    border: 1px solid red;
    width: calc(100% / 3 - 40px);
}