Colors
CSS offers many ways to represent colors:
Demo: Color Formats
HTML
<div class="named">Named: red</div>
<div class="hex">HEX: #6366f1</div>
<div class="rgb">RGB: rgb(5, 150, 105)</div>
<div class="rgba">RGBA: rgba(239,68,68,0.7)</div>
<div class="hsl">HSL: hsl(271, 81%, 56%)</div> CSS
div { padding: 8px 16px; margin: 4px 0; border-radius: 6px; color: white; font-weight: bold; }
.named { background: red; }
.hex { background: #6366f1; }
.rgb { background: rgb(5, 150, 105); }
.rgba { background: rgba(239, 68, 68, 0.7); }
.hsl { background: hsl(271, 81%, 56%); }Live Output Window
Color Formats
| Format | Example | Notes |
|---|---|---|
| Named | red, blue, tomato | 148 named colors |
| HEX | #ff0000, #f00 | 6 or 3 digit hex |
| RGB | rgb(255, 0, 0) | 0–255 each channel |
| RGBA | rgba(255, 0, 0, 0.5) | RGB + alpha (transparency) |
| HSL | hsl(0, 100%, 50%) | Hue, Saturation, Lightness |
| HSLA | hsla(0, 100%, 50%, 0.5) | HSL + alpha |
Opacity
You can also use the opacity property to make an entire element transparent:
Demo: Opacity
HTML
<div class="opaque">opacity: 1</div>
<div class="semi">opacity: 0.6</div>
<div class="ghost">opacity: 0.3</div> CSS
div { background: #6366f1; color: white; padding: 8px 16px; margin: 4px 0; border-radius: 6px; }
.semi { opacity: 0.6; }
.ghost { opacity: 0.3; }Live Output Window