when to leave space ,when not in CSS?

Question

This is ok(without space):

li.highlight{
    background:#FF9900 none repeat scroll 0 0;
}

This will not work(with space):

l         


        

Answer 1

In the first case you select all li tags with class "highlight". In the second case you select children of li tags with class "highlight".

You should read up on CSS selectors in the W3C specification.