01:nth-child(even):nth-child(2n)偶数番目
02:nth-child()background-color
03:nth-child()background-color
04:nth-child()background-color
05:nth-child()background-color
06:nth-child()background-color
07:nth-child()background-color
01:nth-child(odd):nth-child(2n+1)奇数番目
02:nth-child()background-color
03:nth-child()background-color
04:nth-child()background-color
05:nth-child()background-color
06:nth-child()background-color
07:nth-child()background-color