css - How can I apply styles to multiple classes at once?

Question

I want two classes with different names to have the same property in CSS. I don't want to repeat the code.

.abc {
   margin-left:20px;
}  
.xyz {
   margin-left:20px;
}

<a class="abc">Lorem</a>
<a class="xyz">Ipsum</a>

Answer 1

.abc, .xyz { margin-left: 20px; }

is what you are looking for.