Color in the Digital World

Browsers support many ways to describe color. Understanding their differences helps you flexibly manage design.

1. HEX (Hexadecimal Code)

Most common format: #RRGGBB.

  • #ff0000 — red.
  • #ffffff — white.
  • #000000 — black.

2. RGB and RGBA

Mixing red, green, and blue (from 0 to 255).

background: rgba(255, 87, 51, 0.5); /* 0.5 — 50% transparency */

3. HSL (Hue, Saturation, Lightness) — Human-Friendly Format

Most intuitive format:

  • Hue: 0–360 (position on color wheel).
  • Saturation: 0% (gray) — 100% (vivid).
  • Lightness: 0% (black) — 100% (white).

4. Modern Formats (Future)

New standards like OKLCH and Display P3 allow displaying brighter and more saturated colors that were previously impossible on the web.

When and What to Use?

| Format | When Best | | :--- | :--- | | HEX | For standard colors from mockups. | | RGBA/HSLA | When transparency is needed. | | HSL | When creating a palette (e.g., making a color slightly darker or lighter by changing only one number). |

Tip

In HSL, it's very easy to programmatically change colors. For example, to make the main color (hsl(200, 50%, 50%)) darker for hover state, just decrease lightness: hsl(200, 50%, 30%).