The content attribute of the ":after" pseudo-element in css3: 1. Set to none null value; 2. Set to normal, which will be regarded as none null value; 3. Counter sets the counter and the generated content It is the count of the minimum range of the specified name of the pseudo-class element; 4. Set to string text content; 5. Set to "open-quote" before quotation marks; 6. Set to "close-quote" after quotation marks, etc.
The operating environment of this tutorial: Windows 10 system, CSS3&&HTML5 version, Dell G3 computer.
The content attribute of after in css3
The content attribute is used in conjunction with the :before and :after pseudo-elements to insert content.
Syntax format:
content: normal|none|counter|attr|string|open-quote|close-quote|no-open-quote|no-close-quote|url|initial|inherit;
Possible values:
none Set content to a null value.
normal will be treated as none in :before and :after pseudo-class elements, that is, it is also a null value.
counter sets the counter, the format can be counter(name) or counter(name,style). The generated content is the count of the minimum range of the specified name of the pseudo-class element; the format is specified by style (the default is 'decimal' - decimal number)
attr(attribute) changes the element's attribute attribute is returned as a string. .
string Set text content
open-quote Set front quotation mark
close-quote set Back quotes
no-open-quote Remove the opening quotes of the content
no-close-quote Remove the closing quotes of the content
url(url) Set the link address of a certain media (image, sound, video, etc.)
The example is as follows:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>123</title> <style> p:before { content:"天王盖地虎- "; } p#testID:before { content:none; } </style> </head> <body> <p>宝塔镇河妖</p> <p id="testID">强的很!!!</p> </body> </html>
Output result:
Example is as follows:
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>菜鸟教程(runoob.com)</title> <style> p::before { content: open-quote; } p::after { content: close-quote; } </style> </head> <body> <p>天王盖地虎-宝塔镇河妖</p> </body> </html>
Output result:
(Learning video sharing: css video tutorial)
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