Check out example codes for "html entity for $". It will help you in understanding the concepts better.
Code Example 1
<!DOCTYPE html>
<html>
<head>
<style>
.classname {
background-color: green;
color: white;
}
#idname {
background-color: pink;
color: white;
}
</style>
</head>
<body>
<div class="classname">I am green colour<div>
<div id="idname">I am pink colour</div>
</body>
</html>
Code Example 2
$
$
$
Code Example 3
&
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