#RRGGBBAA table

The CSS Color Module Level 4 introduces new 8 (#rrggbbaa) & 4 (shortened #rgba) character hex notation for color to include the opacity level.

background: rgba(255,255,255,0.8); // rgba() format
background: #ffffffcc; // #rrggbbaa format
background: #fffc; // #rgba format
Alpha % Hex Num

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