JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <div class="click">
        <div class="nadpis">Nadpis 1</div>
        Text k nadpisu 1
    </div>
    <div class="click"> 
        <div class="nadpis">Nadpis 2</div>
        Text k nadpis 2
    </div>
</div>

CSS

.active {
    color: #fff;
    background-color: blue;
}

.click {
    border: 1px black solid;
    margin-bottom: 20px;
}

JavaScript

var test = function () {
    $(".click").hover(function () {
            $(this).children(".nadpis").addClass("active");
        }, function () {
            $(this).children(".nadpis").removeClass("active");
        }
    );
};

$(document).ready(test);