You may use black if you need to.
Here are some fabulous samples from our Design Team:
Now it's your turn! Create something using these colors. If you don't have the exact colors, use the closest you have. Take a photo of your project, post it to your blog and link it up with us here. Please include our link and challenge photo in your blog post and use a direct link to link up with us (not your blog in general.) Most importantly, have fun! You can read our complete rules on our sidebar.