A.hapace B.vspace C.cellspacing D.cellpadding
A.border-left:10pxdashed#f00 B.border-right:10pxdashed#f00 C.border-left:10pxsolid#f00 D.border:10pxsolid#f00
A.transition-delay:none; B.transition-delay:0.3s; C.transition-delay:-1s; D.transition-delay:500ms;
A.padding属性是复合属性 B.必须按顺时针顺序采用值复制原则定义4个方向的内边距 C.其取值可为1到4个值 D.padding的取值不能为负
A.1 B.2 C.3 D.4