From white to black in .05 alpha value increments.
#ffffff#f2f2f2 / rgba(0,0,0,.05)#e6e6e6 / rgba(0,0,0,.1)#d9d9d9 / rgba(0,0,0,.15)#cccccc / rgba(0,0,0,.2)#bfbfbf / rgba(0,0,0,.25)#b3b3b3 / rgba(0,0,0,.3)#a6a6a6 / rgba(0,0,0,.35)#999999 / rgba(0,0,0,.4)#8c8c8c / rgba(0,0,0,.45)#808080 / rgba(0,0,0,.5)#737373 / rgba(0,0,0,.55)#666666 / rgba(0,0,0,.6)#595959 / rgba(0,0,0,.65)#4d4d4d / rgba(0,0,0,.7)#404040 / rgba(0,0,0,.75)#333333 / rgba(0,0,0,.8)#262626 / rgba(0,0,0,.85)#191919 / rgba(0,0,0,.9)#0d0d0d / rgba(0,0,0,.95)#000000