JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <img src="http://placehold.it/250x250&text=Darth+Vader+Yo!" />
    <p class="spoiler">
        <!--Spoiler:-->
        <span>Darth Vader is Luke Skywalker's Father! Noooooooooooo!</span>
    </p>
</body>

CSS

.spoiler > span {
    display: none;
}

JavaScript

//1. Hide spoiler
$(".spoiler span").hide();
//2. Add a button
$(".spoiler").append("<button>Reveal Spoiler!</button>");
//3. When button is pressed
$("button").click(function(){
  //3.1 Show the spoiler
  $(".spoiler span").show();
  //3.2 Get rid of button
  $(this).remove();
  });