What are the css selectors? Summary of css selector usage
This article brings you what are the css selectors? A summary of the use of CSS selectors has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.
1. Selector (device) uses basic syntax
Selector { Attribute 1: Attribute value 1;
Attribute 2: Attribute value 2;
Attribute 3: Attribute value 3;
…..: …….;
}
2. Tag selector (directly use HTML tags as selectors)
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>标记选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p> 标记选择器(直接使用html标签做选择器)</p> </body> </html>
second.css
p{ font-size:34px; text-align:left; text-transform:uppercase; font-family:黑体,宋体; text-indent:3em; text-decoration:line-through; font-weight:bolder; letter-spacing:0.5em; line-height:3px; margin:34px; padding:23px; }
3. Class selector (for each The label sets a class name. CSS can set the style of the label through the class name. Different labels can have the same class name, and they can share the same style.) - In CSS, label name.class name or .class name is used to express
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>类选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text"> 类选择器(为每一个标签设置一个类名,CSS可通过类名为标签设置样式,不同标签类名可以相同, 相同可以共用同一个样式)---CSS中用标签名.类名或者.类名表示 </p> </body> </html>
second.css
.text{ font-variant:small-caps;/*小型大写字母*/ font-family:宋体,黑体; font-style:italic; text-transform:lowercase; font-size:35px; text-indent:3em; text-decoration:overline; font-weight:bold; letter-spacing: 1px; line-height:3em; font-variant:small-caps; text-align:right; }
4.ID selector (set a unique ID for each HTML tag, CSS can set the style for the tag through the id)
——#id value { } is used in CSS to represent
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>ID选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text" id="textp1"> ID选择器(为每一个HTML标签设置一个唯一的ID,CSS可以通过id来为标签设置样式) ----CSS中用#id值{ }来表示 </p> </body> </html>
second.css
.text{ font-variant:small-caps;/*小型大写字母*/ font-family:宋体,黑体; font-style:italic; text-transform:lowercase; font-size:35px; text-indent:3em; text-decoration:overline; } #textp1{ font-weight:bold; letter-spacing: 1px; line-height:3em; font-variant:small-caps; text-align:right; }
5. Contains selectors (descendant selectors: can span generation, cross tags): Contain another tag in one tag
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>包含选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text" id="textp1"> <a href="#" class="link">ID选择器</a> (为每一个html标签设置一个唯一的ID,CSS可以通过id来为标签设置样式) ----CSS中用#id值{ }来表示 </p> </body> </html>
second.css
p a{ text-decoration:none; font-size:25px; background-color:pink; } .text{ font-size:21px; font-style:normal; text-transform:lowercase; text-indent:3em; font-weight:bold; letter-spacing:0.7em; line-height:27px; }
6. Sub-selector (not supported by IE browser): No other tags can be included in the middle; in CSS, tag 1 > tag 2 (sub-tag) is used to represent
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>子选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text" id="textp1"> <a href="#" class="link">子选择器</a> (IE浏览器不支持):中间不能包含其他标签;CSS中 标签1 >标签2(子标签) 表示 </p> </body> </html>
second.css
p>a{ text-decoration:none; font-family:黑体,宋体; } p{ font-size: 23px; }
7. Adjacent Selector: (CSS style is applied to the last tag) Commonly used to set column attributes of the table – CSS uses tag 1….Tag n represents
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>相邻选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text" > 子选择器: (IE浏览器不支持):中间不能包含其他标签;CSS中 标签1 >标签2(子标签) 表示 </p> <p class="text1"> 相邻选择器(CSS样式作用在最后一个标签)常用设置表格的列属性--CSS用标签1+....标签n表示 </p> </body> </html>
second.css
.text+.text1{ color:pink; background-color:gray; font-size:34px; }
8. Union selector: Set styles for multiple tags together, separated by commas
second.css
<!doctype html> <html> <head> <meta charset="utf-8"> <title>并集选择器</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p class="text" > 子选择器: (IE浏览器不支持):中间不能包含其他标签;CSS中 标签1 >标签2(子标签) 表示 </p> <p class="text1"> 并集选择器:多个标签一起设置样式,用逗号隔开 </p> </body> </html>
second.css
.text,.text1{ color:pink; background-color:gray; font-size:34px;}
9. Pseudo class (a certain state of an element, often used to describe the state of a hyperlink: link (unvisited state); visited (visited state); hover (mouse passing state); active (clicking state) CSS tags Name: Status representation
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>伪类</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <a href="" class="a1">伪类</a> </body> </html>
second.css
a:link { color:blue; font-size:53px; text-decoration: none; } a:visited { color:red; font-size:193px; } a:hover { color:green; font-size:73px; } a:active { color:gray; font-size:183px; }
10. Pseudo element (state of an element in an object) tag name in CSS : Pseudo-class representation
Commonly used ones are (first-letter [acts on the first letter of text], first-line [acts on the first line of text])
second.html
<!doctype html> <html> <head> <meta charset="utf-8"> <title>伪类</title> <link href="second.css" type="text/css" rel="stylesheet"> </head> <body> <p>伪元素(某个对象中某个元素的状态)CSS中用标签名: 伪元素常用的有(first-letter[作用于文字首字],first-line[作用于文字首行]) <br>伪元素(某个对象中某个元素的状态)CSS中用标签名: 伪元素常用的有(first-letter[作用于文字首字],first-line[作用于文字首行]) </p> </body> </html>
second.css
p:first-letter{ font-size:200%; } p:first-line{ color:red; }
11 Style priority: Inline selector>ID selector>Class selector (pseudo-class, attribute)>Mark selector
You can use !important; to increase the priority
Related recommendations:
css class selector and id selector
##CSS descendant selector and multi-class selector
css tag selector, id selector, class selector instance
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