Replace text with CSS We could use The Checkbox Hack here to make the text swap entirely CSS. The replacement happens the exact same way, it just happens when an invisible checkbox right before the word is either :checked or not. This means the word needs to be in a label as well, which is able to toggle that checkbox’s state through the for att…

replace-text.css

#example {
  position: relative;
}
#example-checkbox {
  display: none;
}
#example-checkbox:checked + #example:after {
  content: "Hide";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: white;
}

replace-text.html

<input id="example-checkbox" type="checkbox">
<label for="example" id="example">Show</label>