[fhomess]

In OOTP15, the HTML reports change depending on the skin you use. In the default OOTP15 skin, the background is white, so what you're seeing is not unexpected.

In the Dark skin, the reports background is dark gray. In the Classic skin, it's a light gray. There is no background image used by default. The class "ext_bg" is applied to the HTML body tag on each page, and that's what contains the background detail in the CSS files.

The default CSS files used by the reports are located in <OOTP_Install_Dir>/templates and are named "styles_ootp 15 <skin_name>.css". With the exception that the default skin CSS file is just "styles_ootp 15.css".

If you don't want to change it globally, you can change the body background for just that one league in your saved game's news/HTML folder using the stylesheet located there. Just watch out for it being overwritten. I'm not sure if/when that happens.