<h1 class="some-class" id="some-id"> This is a heading </h1>
Because of specificity, just remember that any styling added to the id “some-id” will supersede any styling done to the class of “some-class” assigned to the same h1.
Also, if you have two classes assigned that want to give different colors to the text, whatever is written LAST in your stylesheet will actually be applied. It overwrites the previous class.