Summary

The ::first-line CSS pseudo-element applies styles only to the first line of an element. The amount of the text on the first line depends of numerous factors, like the width of the element, width of the document, and the font size of the text. As all pseudo-elements, ::first-line does not match any real HTML element.

A first line has only meaning in a block-container box, therefore the ::first-line pseudo-element has only an effect on elements with a display value of block, inline-block, table-cell or table-caption. In all other cases, ::first-line has no effect.

Only a small subset of all CSS properties can be used inside a declaration block of a CSS ruleset containing a selector using the ::first-line pseudo-element:

As this list will be extended in the future, it is recommended that you not use any other properties inside the declaration block, in order to keep the CSS future-proof.

In CSS 2, pseudo-elements were prefixed with a single colon character. As pseudo-classes were also following the same convention, they were indistinguishable. To solve this, CSS 2.1 changed the convention for pseudo-elements. Now a pseudo-element is prefixed with two colon characters, and a pseudo-class is still prefixed with a single colon.

As several browsers already implemented the CSS 2 version in a release version, all browsers supporting the two-colon syntax also support the old one-colon syntax.

If legacy browsers must be supported, :first-line is the only viable choice; if not, ::first-line is preferred.

Examples

text-transform

Change the letters of the first line of every paragraph to uppercase.

HTML Content

<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
sed do eiusmod tempor incididunt ut labore.</p>

CSS Content

p::first-line { text-transform: uppercase }

Output

margin-left

Does nothing, margin-left cannot be applied to a first-line pseudo-element.

HTML Content

<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
sed do eiusmod tempor incididunt ut labore.</p>

CSS Content

p::first-line { margin-left: 20px }

Output

text-indent

Does nothing, text-indent cannot be applied to a first-line pseudo-element.

HTML Content

<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit,
sed do eiusmod tempor incididunt ut labore.</p>

CSS Content

p::first-line { text-indent: 20px }

Output

Specifications

Specification Status Comment
CSS Pseudo-Elements Level 4
The definition of '::first-line' in that specification.		 Working Draft Defined more strictly where it can occur.
Generalized allowed properties to typesetting, text decoration and inline layout properties and opacity
Defined the inheritance of ::first-letter.
CSS Text Decoration Level 3
The definition of 'text-shadow with ::first-line' in that specification.		 Candidate Recommendation Allowed the usage of text-shadow with ::first-letter.
Selectors Level 3
The definition of '::first-line' in that specification.		 Recommendation The definition of what is the first line of an element has been reworded. The two-colon syntax for pseudo-elements has been introduced.
CSS Level 2 (Revision 1)
The definition of '::first-line' in that specification.		 Recommendation No significant change, though CSS Level 2 still used the one-colon syntax.
CSS Level 1
The definition of '::first-line' in that specification.		 Recommendation The initial definition used the one-colon syntax.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 1.0 (buggy when using text-transform: issue 129669) 1.0 (1.7 or earlier) 9.0 7.0 1.0 (85) (buggy when using text-transform: issue 3409)
Old one-colon syntax (:first-line) 1.0 (buggy when using text-transform: issue 129669) 1.0 (1.7 or earlier) 5.5 3.5 1.0 (85) (buggy when using text-transform: issue 3409)
Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support ? 1.0 (1) Not supported ? ?
Old one-colon syntax (:first-line) ? 1.0 (1) ? ? ?

See also

Document Tags and Contributors

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 Contributors to this page: Tigt, jswisher, wyrewolwerowany, elektronikLexikon, MusikAnimal, TimothyGu, Sebastianz, Sheppy, teoli, geoyws, anotheruiguy, kscarfone, Azaryah, FredB, eliranmal, brianloveswords, Jürgen Jeka, BijuGC
 Last updated by: Tigt,