Our logo is white on Bulb pink or Bulb blue. That's how it is on the homepage, and, if we could choose, how we'd like it to be all of the time. But life doesn't always work like that. Sometimes the universe conspires to make that impossible. So sometimes you'll find the logo in white on a different coloured background (usually Bulb green).
And in exceptional circumstances (usually when the logo is getting lost or is not prominent enough vs our competitors), the logo appears in Bulb pink on a white background.