Apply style to first element in a row of similar elements

Question

I have the following list (the numbers are just for reference)

alpha1
alpha2


        
      

Answer 1

You use the :not() pseudo-class with an adjacent sibling combinator + to match an .A that is not immediately preceded by an .A:

:not(.A) + .A

You'll also need to use :first-child to select the very first .A element since it's not preceded by anything:

.A:first-child

Combine them, and you have:

:not(.A) + .A, .A:first-child { color: red; }

jsFiddle demo