CodePen Embed - MxJELO

<body class="body" id="body">
    Hello CSS!
</body>

body{
  padding: 10px;
  font-size: 14px;
  background:red; 
}
body.body{
  font-size: 20px;
  background: red;
}
#body{
  background: blue;
}

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