HTML a 标签 http://www.runoob.com/tags/tag-a.html HTML br 标签 http://www.runoob.com/tags/tag-br.html CSS background 属性 http://www.runoob.com/cssref/css3-pr-background.html CSS border 属性 http://www.runoob.com/cssref/pr-border.html JavaScript Date 对象 http://www.runoob.com/jsref/jsref-obj-date.html JavaScript Array 对象 http://www.runoob.com/jsref/jsref-obj-array.html