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The column-rule-style CSS property lets you set the style of the rule drawn between columns in multi-column layouts.

column-rule-style: none;
column-rule-style: hidden;
column-rule-style: dotted;
column-rule-style: dashed;
column-rule-style: solid;
column-rule-style: double;
column-rule-style: groove;
column-rule-style: ridge;
column-rule-style: inset;
column-rule-style: outset;

/* Global values */
column-rule-style: inherit;
column-rule-style: initial;
column-rule-style: unset;

Initial valuenone
Applies tomulticol elements
Inheritedno
Mediavisual
Computed valueas specified
Animation typediscrete
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Syntax

A single <br-style> value.

Values

<br-style> 
Is a keyword defined by border-style describing the style of the rule. The styling must be interpreted as in the collapsing border model.

Formal syntax

<br-style>

where
<br-style> = none | hidden | dotted | dashed | solid | double | groove | ridge | inset | outset

Example

#header {
  -moz-column-count: 3;
  -moz-column-gap: 40px;
  -moz-column-rule-style: solid;
}
<div id="header">
    Lorem ipsum dolor sit amet, consectetur adipiscing elit. 
    Mauris sit amet maximus quam. Fusce tempor metus turpis, sit amet bibendum purus tincidunt sit amet. 
    Etiam pretium tempus nibh id pharetra. Nullam ut fermentum est. Integer ut convallis eros, sed laoreet dui. 
    Quisque semper eget tortor ac tempor. Vestibulum quis risus ac ex ultricies vehicula. 
    Duis placerat elementum lectus, id vulputate urna placerat vel. Ut tincidunt sit amet velit sed imperdiet. 
    Duis et urna et sem ultricies rhoncus fermentum vitae est.
</div>

Specifications

Specification Status Comment
CSS Multi-column Layout Module
The definition of 'column-rule-style' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes)-webkit
50.0[1]
(Yes) 3.5 (1.9.1)-moz
52.0 (52.0)[2]
10 11.10 3.0 (522)-webkit
Unprefixed   (Yes)        
Feature Android Android Webview Edge Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support ? ?
50.0[1]
(Yes) (Yes)
52.0 (52.0)[2]
? ? ? ?
50.0[1]
Unprefixed No support   (Yes)          

[1]  Unprefixed as of Chrome 50.

[2] Unprefixed as of Gecko 52, with prefixed aliases still available.