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Home  >  Article  >  Web Front-end  >  【CSS】Use box model

【CSS】Use box model

WBOY
WBOYOriginal
2016-07-21 14:53:011129browse

Box is the basic concept in CSS, we need to use it to configure the appearance of elements and the overall layout of the document.

1. Apply padding to the element

Applying padding adds white space between the element content and the margin. We can set padding individually for each edge of the content box, or use the padding shorthand property to set all values ​​in one declaration.

If you use a percentage value to specify padding, the percentage is always relative to the width of the containing block, and the height is not taken into account. The code below shows how to apply padding to an element. 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;">
            border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;">10px double black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            background-color</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> lightgray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            background-clip</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> content-box</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            width</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 380px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;">
            padding-top</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 0.5em</span><span style="color: #000000;">;</span><span style="color: #ff0000;">
            padding-bottom</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 0.3em</span><span style="color: #000000;">;</span><span style="color: #ff0000;">
            padding-left</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 0.8em</span><span style="color: #000000;">;</span><span style="color: #ff0000;">
            padding-right</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 0.6em</span><span style="color: #000000;">;</span></strong></span>
        <span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
        15岁的时候再得到那个5岁的时候热爱的布娃娃，65岁的时候终于有钱买25岁的时候热爱的那条裙子，又有什么意义。
        什么都可以从头再来，只有青春不能。
        那么多事情，跟青春绑在一起就是美好，离开青春，就是傻冒。
    </span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

In the code, different padding is applied to each side of the box. The effect can be seen from the rendering below. In addition, the background-clip property is set so that the padding area does not show the background color, which emphasizes the effect of the padding.

You can also use the padding shorthand attribute to set padding for four sides in a declaration. You can specify 1~4 values ​​for this attribute. If 4 values ​​are specified, then they represent the top, right, bottom and left padding respectively. If a value is omitted, the best combination is as follows: if the value on the left is omitted, the value on the right is used by default; if the value on the bottom is omitted, the value on the top is used by default. If only one value is given, the padding on all four sides will be this value.

The following code listing shows how to use the padding shorthand attribute. This example also adds a rounded border, showing how to use padding to ensure that the border does not rise above the element's content. 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;">
            border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;">10px solid black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            background</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> lightgray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            width</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 380px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            border-radius</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;">1em 4em 1em 4em</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;">
            padding</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 5px 25px 5px 40px</span><span style="color: #000000;">;</span></strong></span>
        <span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
        15岁的时候再得到那个5岁的时候热爱的布娃娃，65岁的时候终于有钱买25岁的时候热爱的那条裙子，又有什么意义。
        什么都可以从头再来，只有青春不能。
        那么多事情，跟青春绑在一起就是美好，离开青春，就是傻冒。
    </span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

The effect is shown in the figure below, which shows how the browser displays the rounded borders and padding specified in the code.

If no padding is set, the border will be drawn on the text. Setting padding ensures that there is enough space between the content and the border so this doesn't happen.

2. Apply margins to elements

Margins are the white space between an element’s border and everything surrounding it on the page. Things surrounding it include other elements and its parent element.

Similar to the padding property, even if padding is applied to the top and bottom edges, the percentage value is relative to the width of the containing block. The following code listing shows how to add margins to an element: 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        img</span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;">
            border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 4px solid black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            background</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> lightgray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            width</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 150px</span><span style="background-color: #f5f5f5; color: #000000;">;</span>
        <span style="background-color: #f5f5f5; color: #000000;">}</span><span style="background-color: #ccffcc;"><strong><span style="color: #800000;">
        #second img </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> margin</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 4px 20px</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span></strong></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">div </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="first"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">div </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="second"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

In the code, the two img elements below have 4 pixels of margin applied to their top and bottom edges, and 20 pixels of margins to their left and right sides. You can see the blank area created by the margin around the element from the rendering below. The two img elements above and the two img elements below partially show the img elements before and after the margin is set.

Margins are sometimes not displayed even if the value of a certain margin attribute is set. For example, when you apply margins to an element whose display attribute is set to inline, the top and bottom margins will not be displayed.

3. Control the size of elements

The browser sets the dimensions of the element based on the flow of content on the page. There are several detailed rules that browsers must follow when allocating sizes. These behaviors can be overridden using size-related properties.

The default values ​​of the first three attributes are auto, which means that the browser will set the width and height of the element for us. It is also possible to specify dimensions explicitly using length values ​​and percentage values. The percentage value is calculated based on the width of the containing block (the height of the processed element is also based on this width). The following code listing shows how to set dimensions for an element. 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #ccffcc;"><strong><span style="color: #800000;">
        div </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> width</span><span style="color: #000000;">:</span><span style="color: #0000ff;">75%</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> height</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 100px</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> border</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> thin solid lightseagreen</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span><span style="color: #800000;">
        img </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> background</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> lightgray</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> border</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 4px solid blueviolet</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> margin</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 2px</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> height</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 50%</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span><span style="color: #800000;">
        #first </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> box-sizing</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> border-box</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 50%</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span><span style="color: #800000;">
        #second </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> box-sizing</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> content-box</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span></strong></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="first"</span><span style="color: #ff0000;"> src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="second"</span><span style="color: #ff0000;"> src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

上述示例代码中有三个关键元素，一个div元素包含了两个img元素。显示效果如下，展示了浏览器如何显示这些元素。

div元素是body元素的子元素。当将div元素的宽度表示为75%的时候，意思是告诉浏览器将div的宽度设置为包含块（此处是body内容盒）宽度的75%，而不论其具体值是多少。如果用户调整了浏览器窗口，body元素也会相应被调整，以确保div元素的宽度总是body内容盒宽度的75%。

 

3.1 设置一定尺寸的盒子

前面示例中两个img元素设置了相同的高度值（50%），但两个图片的高度在屏幕上看起来不一样。这是因为使用box-sizing属性改变了其中一个元素应用尺寸属性的区域。

默认情况下，宽度和高度是需要计算的，之后才能应用到元素的内容盒。这里说的是如果设置了元素的高度属性是100px，那么屏幕上的真实高度就是100px，这也算上了顶边和底边的内边距、边框和外边距的值。box-sizing属性允许指定尺寸样式应用到元素盒子的具体区域，也就是不需要自己计算某些值。

 

3.2 设置最小和最大尺寸

可以使用最小和最大相关属性为浏览器调整元素尺寸设置一定的限制。这让浏览器对于如何应用尺寸调整属性有了一定的自主权。

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        img </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;">
            background</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> lightgray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 4px solid blueviolet</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            margin</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 2px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">
            box-sizing</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> border-box</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;">
            min-width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 100px</span><span style="color: #000000;">;</span><span style="color: #ff0000;">
            width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 50%</span><span style="color: #000000;">;</span><span style="color: #ff0000;">
            max-width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 200px</span><span style="color: #000000;">;</span></strong></span>
        <span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">img </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="first"</span><span style="color: #ff0000;"> src</span><span style="color: #0000ff;">="imgs/banana.png"</span><span style="color: #ff0000;"> alt</span><span style="color: #0000ff;">="small banana"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

在代码中，为一个img元素应用了mix-width 和 max-width属性，并将其出事宽度设置为包含块的50%。这样浏览器就有了一定灵活性来调整图像尺寸，使其在代码中定义的最大尺寸和最小尺寸范围内保持50%的关系。浏览器会利用这种灵活性保留图像的高宽比，如下面的显示效果所示：

 PS:浏览器对box-sizing属性的支持情况各不相同。

 

4. 处理溢出内容

如果尝试改变元素的尺寸，很快就会到达某一个点：内容太大，已经无法完全显示在元素的内容盒中。这时的默认处理方式是内容溢出，并继续显示。下面的代码清单创建了一个固定尺寸的元素，由于尺寸太小，无法显示其中的内容。

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;">width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 200px</span><span style="color: #000000;">;</span><span style="color: #ff0000;">  height</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 100px</span><span style="color: #000000;">;</span></strong></span><span style="background-color: #f5f5f5; color: #ff0000;"> border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;">medium double black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
    你的特别不是因为你在创业，不是因为你进了牛企，不是因为你的牛offer，而是因为你就是你，坚信自己的特别，坚信自己的内心，勇敢做自己。
    IT DOESN'T MATTER WHERE YOU ARE, IT MATTERS WHO YOU ARE.
</span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

代码中为p元素的width 和 height 属性指定了绝对值，最终显示在浏览器中的显示效果如下图所示：

可以使用 overflow 属性改变这种行为，下表列出了相关的 overflow 属性。

 

overflow-x 和 overflow-y 属性分部设置水平方向和垂直方向的溢出方式，overflow 简写属性可在一条声明中声明两个方向的溢出方式。下表展示了这三个属性可能的取值。

 

下面代码展示了溢出属性的用法：

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;">width</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 200px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;">  height</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 100px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;">medium double black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span><span style="background-color: #ccffcc;"><strong><span style="color: #800000;">
        p:first-child </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> overflow</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> hidden</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span><span style="color: #800000;">
        p:last-child </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> overflow</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> scroll</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span></strong></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
    你的特别不是因为你在创业，不是因为你进了牛企，不是因为你的牛offer，而是因为你就是你，坚信自己的特别，坚信自己的内心，勇敢做自己。
    IT DOESN'T MATTER WHERE YOU ARE, IT MATTERS WHO YOU ARE.
</span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
    你的特别不是因为你在创业，不是因为你进了牛企，不是因为你的牛offer，而是因为你就是你，坚信自己的特别，坚信自己的内心，勇敢做自己。
    IT DOESN'T MATTER WHERE YOU ARE, IT MATTERS WHO YOU ARE.
</span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

 

5. 控制元素的可见性

可以使用 visibility 属性控制元素的可见性。这个属性跟Javascript一起使用能创建一些比较复杂的效果。其取值如下：

下面的代码展示了如何使用JavaScript和几个按钮元素改变元素的可见性。

 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        tr > th </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;"> text-align</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> left</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> background</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> gray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> color</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> white</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span><span style="background-color: #f5f5f5; color: #800000;">
        tr > th:only-of-type </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;"> text-align</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> right</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> background</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> lightgray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> color</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> gray</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">table</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">tr</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>Rank<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>Name<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>Color<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>Size<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">tr</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">tr </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="firstchoice"</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>Favorite:<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Apples<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Green<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Medium<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">tr</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">tr</span><span style="color: #0000ff;">></span>
        <span style="color: #0000ff;"><</span><span style="color: #800000;">th</span><span style="color: #0000ff;">></span>2nd Favorite<span style="color: #0000ff;"></</span><span style="color: #800000;">th</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Oranges<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Orange<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">><</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>Large<span style="color: #0000ff;"></</span><span style="color: #800000;">td</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">tr</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">table</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>Visible<span style="color: #0000ff;"></</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>Collapse<span style="color: #0000ff;"></</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>Hidden<span style="color: #0000ff;"></</span><span style="color: #800000;">button</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="background-color: #ccffcc;"><strong><span style="color: #0000ff;"><</span><span style="color: #800000;">script</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;">var</span><span style="color: #000000;"> buttons </span><span style="color: #000000;">=</span><span style="color: #000000;"> document.getElementsByTagName(</span><span style="color: #000000;">"</span><span style="color: #000000;">button</span><span style="color: #000000;">"</span><span style="color: #000000;">);
    </span><span style="color: #0000ff;">for</span><span style="color: #000000;">(</span><span style="color: #0000ff;">var</span><span style="color: #000000;"> i </span><span style="color: #000000;">=</span> <span style="color: #000000;">0</span><span style="color: #000000;">;i </span><span style="color: #000000;"><</span><span style="color: #000000;"> buttons.length; i</span><span style="color: #000000;">++</span><span style="color: #000000;">){
        buttons[i].onclick </span><span style="color: #000000;">=</span> <span style="color: #0000ff;">function</span><span style="color: #000000;">(e){
            document.getElementById(</span><span style="color: #000000;">"</span><span style="color: #000000;">firstchoice</span><span style="color: #000000;">"</span><span style="color: #000000;">).style.visibility </span><span style="color: #000000;">=</span><span style="color: #000000;"> e.target.innerHTML;
        }
    }
</span><span style="color: #0000ff;"></</span><span style="color: #800000;">script</span><span style="color: #0000ff;">></span></strong></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

collapse 值只能应用到表相关元素，如tr 和 td。

 

6. 设置元素的盒类型

display 属性提供了一种改变元素盒类型的方式，这想要会改变元素在页面上的布局方式。下表列出了display 属性允许的取值。

 

6.1 认识块级元素

将 display属性设置为block值会创建一个块级元素。块级元素会在垂直方向跟周围元素有所区别。通常在元素前后放置换行符也能达到这种效果，在元素和周围元素之间制造分割的感受，就像文本中的段落。p元素表示段落，其默认样式约定中就包括 display 属性取 block 值。不过block 值可应用到所有元素，其用法如下面代码所示：

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;"> border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> medium solid black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span><span style="background-color: #f5f5f5; color: #800000;">
        span </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;"> display</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> block</span><span style="color: #000000;">;</span></strong></span><span style="background-color: #f5f5f5; color: #ff0000;"> border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> medium double black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> margin</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 2px</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
你的特别不是因为你在创业，不是因为你进了牛企，不是因为你的牛offer，而是因为你就是你，坚信自己的特别，坚信自己的内心，勇敢做自己。
</span><span style="color: #0000ff;"><</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>IT DOESN'T MATTER WHERE YOU ARE, IT MATTERS WHO YOU ARE.<span style="color: #0000ff;"></</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

可以从下图看到span 元素的 display属性 是否设置为 block 值的差别。

 

6.2 认识行内元素

将 display 属性设置为 inline 值会创建一个行内元素，它在视觉上跟周围内容的显示没有区别。

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #ccffcc;"><strong><span style="color: #800000;">
        p </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> display</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> inline</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span><span style="color: #800000;">
        span </span><span style="color: #000000;">{</span><span style="color: #ff0000;"> display</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> inline</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> border</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> medium double black</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> margin</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 2em</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> width</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 10em</span><span style="color: #000000;">;</span><span style="color: #ff0000;"> height</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> 2em</span><span style="color: #000000;">;</span><span style="color: #000000;">}</span></strong></span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
你的特别不是因为你在创业，不是因为你进了牛企，不是因为你的牛offer，而是因为你就是你，坚信自己的特别，坚信自己的内心，勇敢做自己。
</span><span style="color: #0000ff;"><</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>IT DOESN'T MATTER WHERE YOU ARE, IT MATTERS WHO YOU ARE.<span style="color: #0000ff;"></</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

In the above code, the inline value is used for both the p element and the span element. The effect of applying the style can be seen from the rendering below: the text in the p element and span element is not separated from the remaining text, and both are displayed. together.

When using inline values, the browser will ignore certain values ​​such as width, height and margin. In the above example code, the values ​​of the three attributes defined for the span element are not applied to the page layout.

6.3 Understanding inline-block-level elements

Setting the display attribute to the inline-block value creates an element whose box combines block and inline properties. The box appears as an inline element as a whole, which means that vertically the element appears side by side with surrounding content without distinction. But the inside of the box is displayed as a block-level element, so the width, height, and margin properties can be applied to the box. 

<span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">lang</span><span style="color: #0000ff;">="en"</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">charset</span><span style="color: #0000ff;">="UTF-8"</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>Example<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
    <span style="color: #0000ff;"><</span><span style="color: #800000;">style </span><span style="color: #ff0000;">type</span><span style="color: #0000ff;">="text/css"</span><span style="color: #0000ff;">></span><span style="background-color: #f5f5f5; color: #800000;">
        p </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #f5f5f5; color: #ff0000;"> display</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> inline</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span><span style="background-color: #f5f5f5; color: #800000;">
        span </span><span style="background-color: #f5f5f5; color: #000000;">{</span><span style="background-color: #ccffcc;"><strong><span style="color: #ff0000;"> display</span><span style="color: #000000;">:</span><span style="color: #0000ff;"> inline-block</span><span style="color: #000000;">;</span></strong></span><span style="background-color: #f5f5f5; color: #ff0000;"> border</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> medium double black</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> margin</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 2em</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> width</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 10em</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #ff0000;"> height</span><span style="background-color: #f5f5f5; color: #000000;">:</span><span style="background-color: #f5f5f5; color: #0000ff;"> 2em</span><span style="background-color: #f5f5f5; color: #000000;">;</span><span style="background-color: #f5f5f5; color: #000000;">}</span>
    <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span><span style="color: #000000;">
    15岁的时候再得到那个5岁的时候热爱的布娃娃，65岁的时候终于有钱买25岁的时候热爱的那条裙子，又有什么意义。
    什么都可以从头再来，</span><span style="color: #0000ff;"><</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>只有青春不能。<span style="color: #0000ff;"></</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span><span style="color: #000000;">那么多事情，跟青春绑在一起就是美好，离开青春，就是傻冒。
</span><span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<s></s>
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