finished homepage
improve interface
modified /img
modified incorrect links
delete unused themes(acm_class)
shstudent_list modified.

Signed-off-by: Luke <Lazurite>
Revert "shstudent_list modified."

This reverts commit 2005e58ce954375a49705e1137bb33aadb1d9246.
Revert "Revert "shstudent_list modified.""

This reverts commit 1f43b02e5bbab6b8029dfb6a0764f3383739a180.