rgb transparent color
#p1 {background-color: rgba(255, 0, 0, 0.3);} /* red with opacity */
#p2 {background-color: rgba(0, 255, 0, 0.3);} /* green with opacity */
#p3 {background-color: rgba(0, 0, 255, 0.3);} /* blue with opacity */
#p4 {background-color: rgba(0, 0, 0, 0.3);} /* black with opacity */
#p5 {background-color: rgba(255, 255, 255, 0.3);} /* white with opacity */