Read the statement by Michael Teeuw here.
Trying to add a background picture, {Body} doesnt work
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 @oscarkindberg You will not be able to float the layer of grey over top. The background services do not support layering. I had tried multi layers for background images and had to make a single background image myself in Gimp to make it work. 
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 Thanks! 
 No I wasn’t embarrassing enough haha.Got it right now tho! 
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 @Wedee I realised that after several tries and errors. I work in photoshop on a daily basis and I think in layers so to speak. 
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 Yes I fully understand, but in html you can layer exactly like you are thinking, but the tools used by Magic Mirror do not support it yet. I spent several hours thinking I was formatting it wrong until I realized this. 
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 @Wedee Works for me, z-index and opacity does the layering just fine, @oscarkindberg 
 But unless you want the fade to be animated it should be made directly in the image, easier for the raspberry to process.

