JSFiddle - React, Tailwind, and code Playground

HTML

<h1>Pierwszy</h1>
<div class="info">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Maxime aperiam eum perspiciatis quo optio vero quas nostrum nam quae fuga.</div>
<h1>Drugi</h1>
<div class="info warning">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Maxime aperiam eum perspiciatis quo optio vero quas nostrum nam quae fuga.</div>
<h1>Trzeci</h1>
<div class="error">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Maxime aperiam eum perspiciatis quo optio vero quas nostrum nam quae fuga.</div>

CSS

h1 {
  cursor:pointer;
}
.ukryty {
  display: none;
}

JavaScript

var naglowki = document.getElementsByTagName("h1");

for(var i = 0; i <= naglowki.length; i++){
  
  naglowki[i].nextElementSibling.style.display = "none";
  
  naglowki[i].addEventListener("click", function(){


		if(this.nextElementSibling.style.display == "none"){
      this.nextElementSibling.style.display = "block";
    } else {
      this.nextElementSibling.style.display = "none";
    }


  });

}