How to put to classes in same css

In my css file I have.

.class1 {}

.class2 {}

If they both have similar code, is the correct way to group them like this:

.class1 .class2 {}

or

.class1, .class2 {}

thanks.

 

.class1, .class2 {} is correct. It will assign the styles to both class1 and class2.

.class1 .class2 {} would work only if class2 is a child of class1 but it assigns the styles to class2 and not class1.

 

thanks, that helps. I had it the incorrect way in my css.

 

yes, qazu is right, that's the cascading effect of CSS
I suggest CSS: The Missing Manual