Color guides, paired with tools.
Short, practical explanations of the color topics you actually deal with — each one links straight to a free tool so you can try it as you read.
RGB vs HSL vs OKLCH: which color format should you use?
A plain-English comparison of RGB, HSL and OKLCH — how each one models color, where they break down, and when to reach for OKLCH in modern CSS.
WCAG color contrast explained (AA, AAA and the 4.5:1 rule)
What the WCAG contrast ratio means, where the 4.5:1 and 3:1 thresholds come from, and how to fix failing text without redesigning everything.
How to build a color palette that actually works
A repeatable method for building a palette — pick a base, choose a harmony, set a lightness rhythm, and check contrast — with the free tools to do each step.
Hex color codes explained: what #RRGGBB really means
How hex color codes work, how to read #RRGGBB and shorthand like #f00, the alpha channel, and how to convert hex to RGB and HSL.
Designing for color blindness: a practical guide
How color-vision deficiencies change what users see, why you should never rely on color alone, and how to test your palette for colorblind users.