Well, I have the same problem with the same version of limesurvey.
Quick workaround : copy the file jqgrid.css from one of the styles directory and css subdir (I selected Styles/Dark Sky/css/jqgrid.css) to the root of the web server, and so it goes.
Not pretty, but efficient if you want to see and edit your tokes .
May be I was unclear about the destination directory.
You can pick one of the jqgrid.css and copy it into your "/var/www/html/limesurvey/" directory.
That did the trick for me.