We’re all familiar with specifying colours in CSS using by defining the mix of red, green and blue light required to achieve our tone. This is fine and dandy, but the colours are all solid, flat, and well, a bit boring.  RGBA , refers to the level of opacity of the colour, we can set not only the red, green and blue values, but also control how much of what’s behind the colour shows through with that . However, do you think there are still some disadvantages of using RGBA ?