Style guides help developers to create useable, well-designed pages. They specify the rules that developers must follow (colors, textures, fonts, icons, etc.) when they implement web pages. Some examples of style guides include:
Please also see http://styleguides.io/ for a more detailed listing of style guides.
Additional Style Resources
Most style guides include colors, textures, fonts, alignment, samples for a variety of common user interface elements, such as forms, images, headings, paragraphs, etc. As an activity, use this style guide template (also shown below) to select the colors, textures, and styles that instantiate your site's look and feel. Try and make a few of them to experiment: