TEST DID NOT COMPLETE

Rules from the stylesheet:

Expected result:

#a:nth-child(n-1) { color: green; }
#b:nth-child(n- 10) { color: green; }
#g:nth-child(-n-1) { color: green; }
#h:nth-child(-n- 10) { color: green; }
#n:nth-child(-n
    - 1) { color: green; }
#o:nth-child(-n
    +13) { color: green; }