Button Blue gets straight to the point. It has enough brightness for calls to action without drifting into cyan. Pair it with a dark navy for reliable contrast, or use pale gray to keep an interface light.

Tints
#2da0ed
#42aaef
#57b3f1
#6cbcf2
#81c6f4
#96d0f6
#abd9f8
#c0e2fa
#d5ecfb
#eaf6fd
#ffffff
Shadows
#2da0ed
#2890d5
#2480be
#2070a6
#1b608e
#165076
#12405f
#0e3047
#09202f
#041018