图标网站
https://www.iconfinder.com
http://www.flaticon.com/

渐变选择器
http://sc.chinaz.com/jiaobendemo.aspx?downloadid=1493221433405

在线配色器
http://sc.chinaz.com/jiaobendemo.aspx?downloadid=142815175416

安全颜色
http://www.bootcss.com/p/websafecolors/