Jak zmienić kolor za pomocą JS

<!DOCTYPE html>
<html>
<head>
<script>
function display()
{
var col=document.getElementById("demo");
col.style.color="#FF0000";
}
</script>
</head>
<body>

<h1>My First JavaScript</h1>
<p id="demo">click on the button below.....</p>

<button onclick="display()">Display</button>

</body>
</html>
Frantic Flatworm