Based on the context and the answer, generate a question. 

Context: Wanting a lighter gray for the lines , I promoted the gray ( # 808080 ) color of the theme to a main color by double clicking it and chose a lighter gray . Finally I created a new style sheet with the new colors . In the whole process I found that Chris Pederick 's Web Developer Extension for Firefox invaluable .

Answer:

To change the colors .



Why did he make a new style ?