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Ok, so I'm not particularly blessed with knowledge about editing forums and such. I don't know proper terms for certain things, so I describe it as it appears to me. This is an ugly white bar and I want it gone. We have tried everything, but none of us really know what we're doing. So far we've been able to run our forum with ease, but this bar has been the bane of our existence, and it has plagued us long enough.
It increases and decreases in size when we change the banner. The larger the banner image, the larger the ugly white bar. The smaller the banner, the smaller the ugly white bar. Our banner is already distorted slightly because of all the resizing we have to do just to keep that bar as small as possible. Can anyone tell me why it's there, what it is, and how to get rid of it for good?

Thanks!