Is it possible in CSS to define a class that duplicates another?

Question

css

Good afternoon, there is a ready-made class, I need it to be identical to Col-lg-5, how can I define it in CSS so that it links, that is, it is identical.

Answer 1

In scss
.class {
@extend .col-lg-5
}

Answer 2

Em…

.some-class,
.col-lg-5 {
    /* .col-lg-5 rules */
}

Answer 3

.Col-lg-5, .You-class {...}