Root directory of laravel project in Cloud9

now it's showing home page http://ift.tt/28ZPqC2

it's my site but i could not make root or homepage in softenum-softenum.c9users.io.

Every time I was trying to change DocumentRoot /home/ubuntu/workspace/ to DocumentRoot /home/ubuntu/workspace/public

But I was not saved by F2 pressing.

Please help me.

via Chebli Mohamed