What does an asterisk mean in front of a colored CSS background?

Question

I see this code. Can someone tell me what * means in front of the background color, and does it matter in a modern browser? Please note that this is the CSS used in Bootstrap 2.3. Also, what is the purpose of repeating the background when used with a gradient? It's necessary?

background-color: #5bb75b; *background-color: #51a351; background-image: linear-gradient(to bottom, #62c462, #51a351); background-repeat: repeat-x; 

Answer 1

Background Question:

 .classABC { background: #000; /* modern browsers */ *background: #333; /* IE 7 and below */ _background: #FFF; /* IE6 exclusively */ } 

It is used for older versions of IE.

Question with background repetition:

There is no particular use. As you seem to know, it repeats images along the x axis. Perhaps there are images applied to elements / children where necessary.