JSFiddle - React, Tailwind, and code Playground

by mauricederegt

HTML

<div class="schedule schedule-261 event">
        <h4>Class A</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-283 event">
        <h4>Class B</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-290 event">
        <h4>Class C</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-261 event">
        <h4>Class A</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-290 event">
        <h4>Class C</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-300 event">
        <h4>Class D</h4>
        <p>Lorem ipsum...</p>
    </div>
    <div class="schedule schedule-261 event">
        <h4>Class A</h4>
        <p>Lorem ipsum...</p>
    </div>

CSS

.someClass {
    background-color: #ff0000;
}

JavaScript

$(".schedule").each(function () {
    var cls = this.className.match(/schedule-\d+/);
    if (cls.length === 0) return;

    var els = $(".schedule." + cls); 
    if (els.not(this).length > 0) {
        els.addClass("someClass");        
    }
});