JSFiddle - React, Tailwind, and code Playground

HTML

<table class="zvyrazneni">
    <tr><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td></tr>
    <tr><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td></tr>
    <tr><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td></tr>
    <tr><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td><td>Ahoj</td></tr>
</table>

CSS

.active {
    background-color: #000;
    color: #fff;
}

JavaScript

$(".zvyrazneni td").click(function () {
    $(".active").removeClass("active");
    $(this).addClass("active");
});