Hello Rostyslav,
It might happen because of various reasons. Unfortunately, I don’t have an online CSS that I can edit. In my opinion, the best way is to include background: 'your colour'" to detect that the style is applied. I would suggest that it might happen because of @media print { string at the beginning of the file, as it is not applied on the web page, but it is applied in the exported file: http://snippet.dhtmlx.com/6f72b6490
Please try reproducing the issue in the snippet above, after that click on the “share” button and send me the link. I will try to reproduce it locally and find what might be wrong.
Hello,
Thank you. The export server needs to access the CSS file, that’s why including local files may not work.
But using your file, I was able to find a bug. Looks like, everything works correctly if you use the standalone module, but it doesn’t work if you use the online export server.
I added that bug in the tracker and it will be fixed in the future.