You can create all kinds of vertical patterns with a narrow background repeat. The problem is when you decide you need to do something different with your page — a graphic larger than the column, clashing banner ads, and so on. Remember to use as few, "browser-safe" colors as possible to get the maximum compression. By the way, just because a color is "browser-safe" doesn't make it "monitor safe". A verdant green on your monitor can appear pea-soup green on the next one.

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