freeCodeCamp/guide/english/css/box-shadow/index.md

title
Box Shadow

Box Shadow

The box-shadow property attaches one or more shadows to an element. It's an option that gives you the power to easily design wonderful shadow effects. It works just like the text-shadow property in that they are both used to create a drop shadow, which will create a darker version of the element just behind it and slightly offset. Box shadows are a great way to elevate the visuals of your web page.

A box shadow can be described with several properties including:

• X and Y offset from the element
• blur and spread radius
• color

Syntax:

div {
  box-shadow: none | [inset? && [ <offset-x> <offset-y> <blur-radius>? <spread-radius>? <color>? ] ]#
}

• inset (default: none)

If not specified, the shadow is assumed to be a drop shadow (as if the box were raised above the content). The presence of the inset keyword changes the shadow to one inside the frame.

• offset-x offset-y

These are two length values to set the shadow offset. specifies the horizontal distance. Negative values place the shadow to the left of the element. offset-y specifies the vertical distance. Negative values place the shadow above the element. See length for possible units.

• blur-radius (default: 0)

This is a third length value. The larger this value, the bigger the blur, so the shadow becomes bigger and lighter. Negative values are not allowed. If not specified, it will be 0 (the shadow's edge is sharp).

• spread-radius (default: 0)

This is a fourth value. Positive values will cause the shadow to expand and grow bigger, negative values will cause the shadow to shrink. If not specified, it will be 0 (the shadow will be the same size as the element).

• color

This value is used to set the color of the shadow, usually defined with hex #000000, rgba value rgba(55,89,88,0.8) or rgb value rgb(55,89,88).

Extended

To maximize compatibility, it is recommended that you declare box shadow properties for moz-appearance and webkit, this extends the normal syntax to:

div{
  box-shadow: none | [inset? && [ <offset-x> <offset-y> <blur-radius>? <spread-radius>? <color>? ] ]#
  -moz-box-shadow: none | [inset? && [ <offset-x> <offset-y> <blur-radius>? <spread-radius>? <color>? ] ]#
  -webkit-box-shadow: none | [inset? && [ <offset-x> <offset-y> <blur-radius>? <spread-radius>? <color>? ] ]#
}

However, this step can be ignored if it is creating confusion, as moz property and webkit property will only work in specific applications such as Firefox, and are not on a standards track.

Examples

Basic use

div {
  width: 200px;
  height: 50px;
  background-color: #333;
  box-shadow: 10px 10px 5px #ccc;
}

10px - offset-x 10px - offset-y 5px - blur #ccc - light gray color

It will display

Inside box shadow

div {
  width: 200px;
  height: 50px;
  background-color: #333;
  box-shadow: inset 10px 10px 5px #ccc;
}

It uses very similar code, but with inset value, which displays shadow inside the div element.

Multiple box shadows

div {
  width: 200px;
  height: 50px;
  background-color: #333;
  box-shadow: inset 10px 10px 5px #ccc, 10px 10px 5px #ccc;
}

You can combine the previous two pieces of box-shadows using a comma to get multiple box shadows on the same div

More Information

• Docs: MDN