• Always prefer classes
• Co-locate component code
• Use consistent class namespacing
• Maintain a strict mapping between namespaces and filenames
• Prevent leaking styles outside the component
• Prevent leaking styles inside the component
• Respect component boundaries
• Integrate external styles loosely

"CSS Colorguard helps you maintain the color set that you want, and warns you when colors you've added are too similar to ones that already exist. Naturally, it's all configurable to your tastes."