What is the difference between the selectors ".class.class" and ".class .class"?

  1. .name1.name2

    means a div or an element having both classes together, for example:

    <div class="name1 name2">...</div>
    

  1. .name1 .name2

    means a div or an element which has a class name1 and any of its child nodes having class name2

    <div class="name1">
        <div class="name2">
            ...
        </div>
    </div>
    

.class .class matches any elements of class .class that are descendants of another element with the class .class.

.class.class matches any element with both classes.