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mystyle.scss

mystyle.css

mypage.html

$myColor: red;

h1 {
  $myColor: green !global;
  color: $myColor;
}

p {
  color: $myColor;
}

h1 {
  color: green;
}

p {
  color: green;
}

<!DOCTYPE html>
<html>
<link rel="stylesheet" href="mystyle.css">
<body>

<h1>Hello World</h1>

<p>This is a paragraph.</p>

</body>
</html>