How to add an icon to existing social networks?

Question

css

It turned out like this, tell me how to add your icon, if they are all enclosed in one file all-icons.png
in css looks like this

.social-icons.facebook {
  background-position: -45px -30px;
}
.social-icons.facebook:hover {
  background-position: -75px -30px;[/code]

how to add vk icon let's say? what would she be
.social-icons.vk

Answer 1

Read about sprites.