https://unpkg.com/dark-light-element@latest/demo.html
Use npm:
npm install --save dark-light-element
Use CDN:
<script type="module" src="https://unpkg.com/dark-light-element"></script>
<!DOCTYPE html>
<html lang="en">
<head>
<title>🌒 toggles dark mode</title>
<meta charset="utf-8" />
<script type="module" src="https://unpkg.com/dark-light-element"></script>
</head>
<body>
<dark-light-element></dark-light-element>
</body>
</html>