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Explain in detail the basic knowledge points of CSS

亚连

May 17, 2018 pm 09:47 PM

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1. Concept

CSS (Cascading Style Sheets): Cascading style sheets after CSS styles, cascading: use different adding methods to the same HTML tag Add styles, all styles work together on the tag; style: add the effects that need to be displayed to the HTML tag.

is mainly used to set the appearance display style of the text content, image shape, and layout of the HTML page.

Function: CSS makes the page more beautiful; CSS Div makes the layout more flexible.

Rules: Style selectors are strictly case-sensitive, but attributes and attribute values are not.

Multiple attributes are separated by English semicolons

If the attribute value consists of multiple The word composition, enclosed in English quotes

style selector is as follows:

<font style="color:red;size:14;"></font>

2. Introduce CSS style

1 .Inline style

<body>  
    <!--行内样式-->  
    <font style="color:red">浅笑安然</font><br />  
</body>

2.Internal style

<head>  
    <meta charset="UTF-8">  
    <title></title>  
    <!--内部样式-->  
    <style type="text/css">  
        font{  
            color: red;  
        }  
    </style>  
</head>

3.External style

Reference external style:

<head>  
        <!--外部样式-->  
    <link rel="stylesheet" type="text/css" href="../css/outer.css"/>  
</head>

CSS file settings:

/*font style setting*/

font{  
    color:green;  
}

Priority: Inline styles have the highest priority, internal styles and external styles are closest to each other

3. Selector

1. Element selector

<font >浅笑安然</font>  
[html] view plain copy
/*元素选择器*/  
font{  
    color: red;  
}

2. ID selector: #id name{}

<font id="flower">心若浮沉</font>  
[html] view plain copy
/*ID选择器*/  
#flower{  
    color: blue;  
}

3. Class selector: .class class name {}

<font class="happy">清风自来</font>  
[html] view plain copy
/*类选择器*/  
.happy{  
    color:gold;  
}

4. Attribute selector: tag name [attribute='attribute value']

Text:

/*属性选择器*/  
input[type=text]{  
    background-color: brown;  
}

5. Contains selectors: parent tags and child tags

<p class="day">  
    <font>  
        今天天气好晴朗  
    </font>  
</p>

/*包含选择器*/  
.day font{  
    color:orangered;  
}

4. CSS styles

1.border width high

2.display: block block-level attribute inline row-level attribute none hidden attribute inline-block: block-level element in a row, with width
block-level element p; row-level element span

3.Font: color font-size background-color

4.float: float clear: clear float

##5. Box model

margin: outer margin, box and box, set clockwise, if not set, it will be symmetrical

border: border line

padding: inner edge Distance, box and content

The box model is the box we commonly use. In real life, it has its own border thickness, the distance from the objects inside, and the distance between the box itself and the outside world.

Summary:

CSS cascading style is a combination of multiple styles that work together on the label. Whether it is the use of selectors, property settings, or the use of box models, it is basically In order to change the style of an HTML page, a variety of forces work to produce a beautiful page.

Detailed explanation of the steps for PHP dynamic compression of js and css files

JS CSS3 realizes the interactive magnification effect of mouse and image

An example of a button realized with a picture using CSS

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