location / {
  #Redirect everything that isn't a real file to index.php
  try_files $uri $uri/ /index.php$is_args$args;
}

#If you want a single domain name at the front and back ends
location /admin {
  try_files $uri $uri/ /admin/index.php$is_args$args;
}
location /mobile {
  try_files $uri $uri/ /mobile/index.php$is_args$args;
}