If you have a value that you use often, you can store it in a variable. You could use this to define color schemes, for example. You would only have to define your scheme once and then you could use it throughout your stylesheets.
To define a variable, you must prefix its name with the $ symbol. (Like you would in PHP.)
You can store any valid CSS property value inside a variable. Such as colors, fonts or URLs.
Example #1:
$foreground: #FAFAFA;
$background: rgb(0, 0, 0);
body {
color: $foreground;
background-color: $background;
}
p {
color: rgb(25, 25, 20);
background-color: $background;
}