Best Practices for Using Colors and Units


Writing CSS is not only about making styles work.

It is about making designs clear, consistent, and easy to maintain.

Why Best Practices Matter

In real projects, poor color and unit choices lead to:

  • Hard-to-read pages
  • Broken layouts
  • Difficult maintenance

Rule 1: Use a Limited Color Palette

Professional websites use only a few main colors.

Rule 2: Always Maintain Good Contrast

Text must be easy to read on any background.

This ensures good readability.

Rule 3: Use rem for Font Sizes

rem makes text scalable and consistent.

Now all text sizes follow a clear system.

Rule 4: Use Relative Units for Layout

Relative units make layouts flexible.

This adapts better to different screen sizes.

Rule 5: Avoid Using Only px Everywhere

Using only pixels makes designs rigid.

Rule 6: Be Consistent

Use the same units and color system across the project.

Rule 7: Test on Different Screens

Always test your design on:

  • Large screens
  • Small screens
  • Mobile devices

Why This Matters for Jobs

Employers look for developers who care about design quality.

Clean use of colors and units shows professionalism.

Common Beginner Mistakes

  • Using too many bright colors
  • Mixing px, em, rem randomly
  • Ignoring mobile users

Practice Task

Review one of your pages and:

  • Reduce the number of colors
  • Change font sizes to rem
  • Replace fixed widths with %

Chapter Summary

In this chapter, you learned how to use colors, units, and spacing to create clean and responsive designs.

What You Will Learn Next

In the next chapter, you will learn about CSS layout techniques.