Try it Editor

<!DOCTYPE html>
<html>
<head>
<style>
.uppercase {
  text-transform: uppercase;
}
 
.lowercase {
  text-transform: lowercase;
}
 
.capitalize {
   text-transform: capitalize;
}
</style>
</head>
<body>
 
<p class="uppercase">This is a uppercase paragraph.</p>
<p class="lowercase">This is a lowercase paragraphp.</p>
<p class="capitalize">This is a capitalize case paragraph.</p>
 
</body>
</html>