JSFiddle - React, Tailwind, and code Playground

HTML

<button id="btn" class="default_btn">ButtonText</button>

CSS

.default_btn{
    background-color: #0f0;
    width:100px;
}
.default_hover_btn{
    background-color: #f00;
}

JavaScript

$("#btn").hover(function() {
        $(this)
            .removeClass("default_btn")
            .addClass("default_hover_btn");
    }, function() {
        $(this)
            .removeClass("default_hover_btn")
            .addClass("default_btn");
});