Problems with popups in yootheme template

[Thomas Venugopal]

I already tried this solution: http://www.reviewsforjoomla.com/forum/index.php?topic=4412.0

 

But it doesn't work for me. All popups appear without a background. I could hardcode a background color but I thing this is not a solution. See attached screenshot:

[Alejandro]

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[Thomas Venugopal]

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[Thomas Venugopal]

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