JSFiddle - React, Tailwind, and code Playground

HTML

<select class="mySelect">
    <option>Option 1</option>
    <option>Option 2</option>
</select>

CSS

.mySelect
{
    /*height: 20px;*/
}

@media only screen and (max-width: 599px) {
.mySelect
{
    height: 40px;
}
}