<h1>Hello World</h1>
html, body {
  border: 3px dashed black;
  background-color: white;
}

h1 {
  color: green;
  mix-blend-mode: difference;
}

h1::after {
  content: 'Hello from the other side';
  position: absolute;
  bottom: 50px;
  right: 50px;
}

External CSS

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External JavaScript

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