The default colors of your site have passed accessibility tests that account for things like contrast and perceptibility. If you opt to change them, be sure to follow accessibility guidelines and tools to ensure continued compliance.
Most of the colors of your ScreenSteps site can be customized to fit your branding. You can change them by following these steps:
You'll likely want to repeat this process for each page type in order to create a cohesive color scheme across your site.
Click the swatch next to the color name you want to adjust, update the color using the color picker that appears, then click outside the tool to close it.