超级链接 渐变样式

由灰色渐变成蓝色，样式如下

 

a {

  color: #999999;

  color: rgba(155,155,155,.5);

  -webkit-transition: all .2s ease-in-out;

     -moz-transition: all .2s ease-in-out;

          transition: all .2s ease-in-out;

}

a:hover {

  color: #7777FF;

  text-shadow: 0 0 10px rgba(125,125,125,.25);

}