CSS十六种基本颜色
aqua水绿#00FFFF
black黑＃000000
blue蓝＃0000FF
fuchsia紫红＃FF00FF
gray灰＃808080
green绿＃008000
lime浅绿#00FF00
maroon褐＃800000
navy深蓝＃000080
olive橄榄＃808000
purple紫＃800080
red红＃FF0000
silver银＃C0C0C0
teal深青＃008080
white白＃FFFFFF
yellow黄＃FFFF00