CSS colors

http://sixrevisions.com/css/css-colors/  is an awesome post to explain the basics of CSS colors.

There are six ways to declare CSS colors:

• Hexadecimal notation
• RGB
• RGBA
• HSL (Hue, Saturation and Lightness)
• HSLA
• Color keywords

transparent Color Keyword
The transparent color keyword is simply a way to say that the color has 0% opacity.

currentColor Color Keyword
The currentColor color keyword is a convenience keyword that just means the color being declared is equal to the CSS color property value.

As we write SASS for CSS, I think it is best practice to use variable and hex color definition.