Using HTML, CSS create a list with floating headings for each section

Preview:

A: Aaban; Aabel; Aabheer; Aadam
B: Baabul; Baalaji; Baalkrishan; Baanke Bihaari
C: Caddam; Cameroon; Campbell; Cane
D: Daanesh; Dadvar; Daghan; Daivya; Daamini
E: Eadmer; Earnest; Eddward; Edmond