So each version of android will get a class applied to them, so you could do something like this
.platform-android4_1 {
/*Any styles for android 4.1*/
}
.platform-android4_3 {
/*Any styles for android 4.3*/
}
.platform-android4_4 {
/*Any styles for android 4.4*/
}
.platform-android5_0 {
/*Any styles for android 5.0*/
}