<!--   
a {font-size:16px}   
a:link {color: blue; text-decoration:none;} //未访问：蓝色、无下划线   
a:active:{color: red; } //激活：红色   
a:visited {color:purple;text-decoration:none;} //已访问：purple、无下划线   
a:hover {color: red; text-decoration:underline;} //鼠标移近：红色、下划线   
-->