Pick any colour you like because yellow goes with just about everything. Then you'll need to narrow down the exact tone/shade of the accent colour so it works with the particular tones of your furniture and paint. For example, blue is an excellent contrast to yellow. A strong turquoise would be beautiful, or a cobalt blue. Put colours into the search terms on Houzz and see how other people have incorporated yellow and other colours into their interiors.

Your title says window treatment, but your content is mentioning adding another color. What is your dilemma?

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