JSFiddle - React, Tailwind, and code Playground

by Sergei Sokolov

HTML

<div id="test"></div>
<button class="button">переключить</button>

CSS

#test {
	width:100px;height:100px;
	background-color:green;
}

.boxed {
	border:3px solid purple;
	background-color:yellow !important;
}

JavaScript

$(document).ready(function(){
  var key = "__body_boxed__";
	var boxedState = false;
  if( localStorage && JSON.parse(localStorage.getItem(key))) {
	  boxedState = true;
	  $("#test").toggleClass("boxed");
		$("#test").text("LS boxed!")
	}
  $(".button").click(function(){
    $("#test").toggleClass("boxed");
		boxedState = !boxedState;
    localStorage && localStorage.setItem(key, JSON.stringify(boxedState));
    return false;
  });
});