rgba code example
Example 1: css opacity background color
background: rgba(255, 255, 255, 0.25);
Example 2: rgba red color
rgb(255,0,0) /*red*/ Hex #FF0000
Example 3: rgba green color
rgb(0,128,0) /*green*/ Hex #008000
Example 4: background color cs rgba
#p1 {background-color:rgba(255,0,0,0.3);}