JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="mainList">
    <li class="first">i am first</li>
    <li class="second">i am second</li>
    <li class="third">i am third</li>
</ul>

CSS

#mainList {
    display: flex;
    flex-direction: column;
}
.second {
    order: -1;
}