Forget that lucky bamboo plant you ordered online. There’s an easier way to create a happy, Zen-like environment in your office: Pick the right colors. The U.S. Public Health Service did a two-year study of public buildings and found that rooms with certain colors had a 5.5 percent increase in productivity. Namely, a combination of green and red proved most productive. Similarly, “bland” colors like white, black and brown caused a drop in performance, and even correlated to a drop in IQ tests in one study.