In CSS, you use a period (.) to indicate "match on class name" and the octothorp (#) to indicate "match on id".
So:
Code:
<html>
<head>
<style type="text/css">
.funky {
color : magenta;
background-color : lime;
}
#butNotMe {
color : black;
backgroundColor : white;
}
</style>
</head>
<body>
<div class="funky" id="woof">This text will show purple on green</div>
<div class="funky" id="butNotMe">This text will be black on white</div>
<div class="funky" id="zing">Back to purple on green</div>
</body>
</html>
How did you get started in JavaScript, mucking with things like canvas and more, and completely bypass the fundamentals of HTML and CSS??
I think it would be worth your while to go back and catch up on HTML and CSS.
Oh, and by the way, this question has nothing to do with JavaScript.
(Though jQuery uses "." and "#" in the same way as "selectors".)