<html>
  <head></head>
  <body></body>
</html>
body {
  background: linear-gradient(90deg, rgba(139, 0, 0, 0.6) 50%, transparent 0),
  linear-gradient(rgba(139, 0, 0, 0.6) 50%, transparent 0); 
  background-size: 50px 50px;
}

External CSS

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External JavaScript

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