Can somebody explain?

Question

1. input.radioButton, [type="radio"]{} /* "," What does it mean? */

2. input .radioButton, [type="radio"]{} /* "space between input and .radiobutton" What it refers to? */

3. input.radioButton, [type="radio"]{} /* "space between input and .radiobutton" does that make any difefrence? */

Answer 1

This CSS selector refers to an input element whose class name is radioButton or an element with the type radio.

And I think space won't affect the code anyway