how to set background colour i js inline stylel

JavaScript
<!DOCTYPE html>
<html>
   <head>
      <title>HTML Backgorund Color</title>
   </head>
   <body style="background-color:grey;">
      <h1>Products</h1>
      <p>We have developed more than 10 products till now.</p>
   </body>
</html>
Source

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