fix ticket 563
Merge pull request #24 from xiechao06/ticket563

fix ticket 563
ticket 568
Merge pull request #25 from xiechao06/ticket568

ticket 568
fix ticket 574
Merge pull request #27 from xiechao06/ticket574

fix ticket 574
Merge pull request #28 from xiechao06/nav_bar

responsive navbar
fix the display of unauthenticated