Selenium IDE: How to check text color using CSS
style.color will return color if actual DOM element has style attribute. In your case, when color is definied in <style> tag it won't work. This we need you use getComputedStyle(). Still, color returns color in RGB format but you may convert your color manually and verify RGB result.
Like this:
assertEval( "window.document.defaultView.getComputedStyle(window.document.getElementsByClassName('title')[0]).getPropertyValue('color')", "rgb(204, 51, 51)")N.B. It's also recommended to use selenium.browserbot.getCurrentWindow() instead of window. I left window to make snippet shorter.