Please excuse the newbie question. I'm guite new to WAB and at the moment I'm trying to customize Popups of my webmap template. I downloaded the webmap and got in running on my server. Most of the attributes I'd like to change seemsto be written in the file esri.css and it seems to be hosted by ESRI servers. Is there a chance to edit this css file? If not, ist there a work around/better way to customize the pop ups?