The ::first-line pseudo-element is for applying styles to the first line of an element. Imagine a paragraph that is several lines long (like this one!). ::first-line allows you to style that first line of text. You could use it to make it larger or set it in small-caps as a stylistic choice. The amount of text targeted by this pseudo-element depends on the several factors like line length, viewport width, font-size, letter-spacing, word-spacing. As soon as the line breaks, the text after that is no longer selected. Note that there is no actual DOM element being selected here (thus “pseudo” element).
This pseudo-element only works on block-level elements (when display is set to either block, inline-block, table-caption, table-cell). If set on an inline element, nothing happens, even if that inline element has a line break within it.
Also note that not all properties can be used in a ruleset containing ::first-line. Mostly:
.element::first-line {
font-style: ...
font-variant: ...
font-weight: ...
font-size: ...
font-family: ...
line-height: ...
color: ...
word-spacing: ...
letter-spacing: ...
text-decoration: ...
text-transform: ...
background-color: ...
background-image: ...
background-position: ...
background-repeat: ...
background-size: ...
background-attachment: ...
}The official CSS specification tells User Agents can allow other properties if they feel like it:
UAs may apply other properties as well.
The following demo shows how ::first-line is able to override any kind of specificity, even !important.
This is because the pseudo-element is treated like a child element, not just a part of the parent element. So the rules you apply to it are just for it, the parent rules just may cascade to it.
Also, try resizing your browser to see how behave the pseudo-element when the viewport width change.
There is no :last-line or :nth-line, even though that would be cool.
This browser support data is from Caniuse, which has more detail. A number indicates that browser supports the feature at that version and up.
| Chrome | Firefox | IE | Edge | Safari |
|---|---|---|---|---|
| 9 | 3.5 | 9 | 12 | 5.1 |
| Android Chrome | Android Firefox | Android | iOS Safari |
|---|---|---|---|
| 146 | 148 | 3 | 5.0-5.1 |
There’s a really annoying bug in Chrome that prevents text-transform: uppercase from working on ::first-line:
https://code.google.com/p/chromium/issues/detail?id=129669
https://code.google.com/p/chromium/issues/detail?id=142827
Might want to add that to the article because it’s a very old bug (known since Chrome 3 or earlier) and nobody on the Chrome team seems to be following up on it.
That is unbelievable. How long has this bug been known, and there is absolutely no attempt to remedy it?
So I know it’s not ideal, but until they fix this bug I’ve found this to be a helpful work around:
font-variant: small-caps;
Like I said, not ideal, but it’s been enough for some projects I’ve worked on.
This library helped me out http://zencode.in/lining.js/ .. seems overkill, but it works.
Nobody @GoogleChrome seems to care about it. :-) You can use span or something to achieve the desired effect still.
not really. because the ::first-line is independent of html markup, and therefore suits a fluid layout much better than span tags which assumes that this word right here is definitely the last word on this line of text.
Yes, this bug in Chrome / WebKit is awful and persistent and inexplicable. Never thought I’d say it, but Chrome really needs to catch up to IE here.
2016 is almost over and this Chrome bug still exists. Chromium is the new IE.
Worth noting, I just learned Firefox (v41.0.1 at the time of this writing) will not allow :first-line to set line-height to lower than the element’s current setting.
Apparently not necessarily a bug as the spec leaves this up to interpretation by the browser but all others (Chrome, Safari, IE) perform as expected.
Here’s another
::first-linebug I encountered (with fix):