<div id="an_element">I'm an element</div>
body {
  background: #292e39;
  color: #fff;
}

div {
  padding: 1cm; // IN CENTIMETERS
  text-align: center;
  font-size: .75cm; // BECAUSE METRIC SYSTEM
}
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// #1: do something to an element with Javascript

var element = document.getElementById('an_element');

element.textContent = element.textContent + ' with something done to me!';
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