[mg10]

Hello
I'm not sure if this question should be asked in this forum. If so, please, let me know the best one.
This is a problem that appeared after converting from epub to azw3 with Calibre adding a css entry to reduce left and right margins. This works fine on my Scribe but not on my new PW11 after upgrading it to the latest firmware version.
After the upgrade, started some errors when opening or moving inside the books. If I don't include the code in the css page the converted book works fine but again appear the huge default margins.
The used code is:

html {
margin-left: -45px;
margin-right: -45px
}
And the error that appears in the books:
"An error occurred. If you purchased this item from Amazon, delete the item and download it from the Cloud."

Do you think it's a bug in the new firmware or can the code be modified to fix this behavior?
Thanks