replace favicon.ico
增加了指向人人等主页的图标。
改变joinus指向
Merge branch 'NewWebsite' of https://github.com/mulab/www into NewWebsite
make some big news

I’m excited!
增大项目介绍与上边的边距
Merge branch 'NewWebsite' of https://github.com/mulab/www into NewWebsite
增大顶端间距。
open things in new tab
better code style for contact icons
修改背景色
Merge branch 'NewWebsite' of https://github.com/mulab/www into NewWebsite
修改按钮布局
修改图标，全部换成圆形。
simple animation
Merge branch 'NewWebsite' of https://github.com/mulab/www into NewWebsite