border

Summary

The border CSS property is a shorthand property for setting the individual border property values in a single place in the style sheet. border can be used to set the values for one or more of: border-width, border-style, border-color.

Like all shorthand properties, a missing value for one of the longhand properties is set to the corresponding initial value. Also note that border-image, though not settable using this shorthand, is reset to its initial value, that is, none. This allows to use border to reset any border settings set earlier in the cascade. As the W3C intends to preserve this property in future level of the spec, it is recommended to use this method to reset border settings.

• Initial value the concatenation of the initial values of its longhand properties:
  • border-width: the concatenation of the initial values of its longhand properties:
    • border-top-width: medium
    • border-right-width: medium
    • border-bottom-width: medium
    • border-left-width: medium
  • border-style: the concatenation of the initial values of its longhand properties:
    • border-top-style: none
    • border-right-style: none
    • border-bottom-style: none
    • border-left-style: none
  • border-color: the concatenation of the initial values of its longhand properties:
    • border-top-color: currentColor
    • border-right-color: currentColor
    • border-bottom-color: currentColor
    • border-left-color: currentColor
• Applies to all elements
• Inherited no
• Media visual
• Computed value as each of the properties of the shorthand:
  • border-width: as each of the properties of the shorthand:
    • border-bottom-width: the absolute length or 0 if border-bottom-style is none or hidden
    • border-left-width: the absolute length or 0 if border-left-style is none or hidden
    • border-right-width: the absolute length or 0 if border-right-style is none or hidden
    • border-top-width: the absolute length or 0 if border-top-style is none or hidden
  • border-style: as each of the properties of the shorthand:
    • border-bottom-style: as specified
    • border-left-style: as specified
    • border-right-style: as specified
    • border-top-style: as specified
  • border-color: as each of the properties of the shorthand:
    • border-bottom-color: If the value is translucent, the computed value will be the rgba() corresponding one. If it isn't, it will be the rgb() corresponding one. The transparent keyword maps to rgb(0,0,0,0).
    • border-left-color: If the value is translucent, the computed value will be the rgba() corresponding one. If it isn't, it will be the rgb() corresponding one. The transparent keyword maps to rgb(0,0,0,0).
    • border-right-color: If the value is translucent, the computed value will be the rgba() corresponding one. If it isn't, it will be the rgb() corresponding one. The transparent keyword maps to rgb(0,0,0,0).
    • border-top-color: If the value is translucent, the computed value will be the rgba() corresponding one. If it isn't, it will be the rgb() corresponding one. The transparent keyword maps to rgb(0,0,0,0).
• Animatable as each of the properties of the shorthand:
  • border-color: as each of the properties of the shorthand:
    • border-bottom-color: yes, as a color
    • border-left-color: yes, as a color
    • border-right-color: yes, as a color
    • border-top-color: yes, as a color
  • border-style: no
  • border-width: as each of the properties of the shorthand:
    • border-bottom-width: yes, as a length
    • border-left-width: yes, as a length
    • border-right-width: yes, as a length
    • border-top-width: yes, as a length
• Canonical order order of appearance in the formal grammar of the values

Syntax

Formal syntax:  <br-width> || <br-style> || <color>

Values

<br-width>

Default value medium is used if absent. See border-width.

<br-style>

Default value none is used if absent. See border-style.

<color>

A <color> denoting the color of the border. If not set, its default value is the value of the element's color property (the text color, not the background color). See border-color.

Examples

border

HTML Content

<div class="brd"> look at my borders </div>
<p>you can play with the css bellow to test properties changes</p>
<style contenteditable>
  .brd { border: 1px solid black }
</style>

CSS Content

.brd { border: 1px solid black}

style { 
  border: 1px dashed black;
  display:block;
} 

Border demo

Click the different examples to see them in action:
<button>border: 2px solid #ccc;width: 300px</button>
<button>border: 20px solid #ccc;width: 300px</button>
Try it yourself: <input type="text" id="cd" value="border: 14px red dashed">

<div id="example">Result</div>

body {font: 14px/1.5 'Open Sans',sans-serif;}
button { color: #369; border: none; font-size: 14px; padding: 10px 0; background: transparent; display: block;}

document.addEventListener('click', function(ev) {
    var t = ev.target;
    var out = document.getElementById('example');
    if (t.tagName === 'BUTTON') {
var str = t.innerHTML;
        out.style = str + ';transition: 0.5s';
    }
}, false);
document.getElementById('cd').addEventListener('keyup', function(ev){
document.getElementById('example').style = this.value + ';transition: 0.5s';
}, false);

Specifications

Browser compatibility

See also

• Border-related properties: border, border-width, border-style, border-color, margin, padding
• border-radius-related CSS properties: border-top-left-radius, border-top-right-radius, border-bottom-right-radius, border-bottom-left-radius
• Padding-related properties: padding, padding-top, padding-right, padding-bottom, padding-left, border, margin
• Margin-related properties: margin, margin-top, margin-right, margin-bottom, margin-left, border, padding
• Outline-related properties: outline, outline-width, outline-style, outline-color, outline-offset