Nginx Warnings - How to fix?

Hey!

When I I try to restart nginx, after editing sudo nano /etc/nginx/sites-available/default, I get this fail response:

Restarting nginx nginx [fail]

I then do nginx -t and get this message:

nginx: [alert] could not open error log file: open() "/var/log/nginx/error.log" failed (13: Permission denied)
2016/04/28 20:06:07 [warn] 6121#0: the "user" directive makes sense only if the master process runs with super-user privileges, ignored in /etc/nginx/nginx.conf:1
2016/04/28 20:06:07 [emerg] 6121#0: unexpected "}" in /etc/nginx/sites-enabled/default:84
nginx: configuration file /etc/nginx/nginx.conf test failed

So what am I doing wrong and how can I fix it? It seems there is two things going wrong?

Thanks in advance.