HTML basics (3) css style sheet

CSS (Cascading Style Sheet, cascading style sheet), which is used to beautify HTMLWeb page.

/*Comment area*/This is the comment syntax

1. Style sheet

(1) Classification of style sheets

1.Inline style sheet

Displayed jointly with HTML, the control is precise, but the reusability is poor and there is more redundancy.

Example:

Inline style sheet

2.Embedded style sheet

is embedded in the web page as an independent area and must be written in the head tag.

3.External style sheet

Create a new CSS file to place the style sheet. If you want to call a style sheet in an HTML file, you need to right-click on the HTML file → CSS Style Sheet → Attach Style Sheet. Generally, link connection is used.

Note: There is no need to write style tags in the css file

Some tags have default margins, which are generally removed when writing style sheet code (other styles can also be set), as follows:

Note: The above picture is to remove the margins and spacing first.

(2) Selector

1.Tag selector. Use tag name as selector.

                                                     

2.class selector. They all start with “.”.

Note: The class selector can be superimposed with the label selector to display different effects.

3.ID selector. Start with “#”.

Note: The ID selector can be superimposed with the tag selector to display different effects.

4.Composite Selector

(1) Separated by "," to indicate juxtaposition.

(2) Separated by spaces to indicate descendants.

(3) Filter ".".

2. Style attributes

(1) Background and foreground

1.Background:

2.Foreground font:

(2) Boundaries and borders

border (table border, style, etc.), margin (off-table spacing). padding (content and cell spacing).

(3) Lists and Blocks

width, height, (top, bottom, left, right) are only useful in absolute coordinates.

css style sheet code display:

css file code:

<span style="color: #008080;"> 1</span> <span style="color: #800000;">@charset "utf-8";
</span><span style="color: #008080;"> 2</span> <span style="color: #008000;">/*</span><span style="color: #008000;"> CSS Document </span><span style="color: #008000;">*/</span>
<span style="color: #008080;"> 3</span> <span style="color: #800000;">*</span><span style="color: #008000;">/*</span><span style="color: #008000;">所有标签起作用，边距和间距都设为0px</span><span style="color: #008000;">*/</span>
<span style="color: #008080;"> 4</span> {
<span style="color: #008080;"> 5</span> <span style="color: #ff0000;">    margin</span>:<span style="color: #0000ff;">0px</span>;
<span style="color: #008080;"> 6</span> <span style="color: #ff0000;">    padding</span>:<span style="color: #0000ff;">0px</span>;}
<span style="color: #008080;"> 7</span> <span style="color: #800000;">p,span   </span><span style="color: #008000;">/*</span><span style="color: #008000;">直接写个标签名字，表示所有的p标签都执行这个样式</span><span style="color: #008000;">*/</span>
<span style="color: #008080;"> 8</span> {
<span style="color: #008080;"> 9</span> <span style="color: #ff0000;">    background-color</span>:<span style="color: #0000ff;">#F6C</span>;
<span style="color: #008080;">10</span> <span style="color: #ff0000;">    color</span>:<span style="color: #0000ff;">#0F0</span>;}
<span style="color: #008080;">11</span> <span style="color: #800000;">p.sp
</span><span style="color: #008080;">12</span> {
<span style="color: #008080;">13</span> <span style="color: #ff0000;">    background-color</span>:<span style="color: #0000ff;">#FF0</span>;
<span style="color: #008080;">14</span> <span style="color: #ff0000;">    color</span>:<span style="color: #0000ff;">red</span>;
<span style="color: #008080;">15</span> <span style="color: #ff0000;">    font-size</span>:<span style="color: #0000ff;">36px</span>;}
<span style="color: #008080;">16</span> <span style="color: #800000;">.main</span><span style="color: #008000;">/*</span><span style="color: #008000;">以.开头，使用class引用此样式表</span><span style="color: #008000;">*/</span>
<span style="color: #008080;">17</span> {
<span style="color: #008080;">18</span> <span style="color: #ff0000;">    height</span>:<span style="color: #0000ff;">50px</span>;
<span style="color: #008080;">19</span> <span style="color: #ff0000;">    width</span>:<span style="color: #0000ff;">300px</span>;
<span style="color: #008080;">20</span> <span style="color: #ff0000;">    background-color</span>:<span style="color: #0000ff;">#0FF</span>;
<span style="color: #008080;">21</span> <span style="color: #ff0000;">    font-size</span>:<span style="color: #0000ff;">45px</span>;}
<span style="color: #008080;">22</span> <span style="color: #800000;">.main p</span><span style="color: #008000;">/*</span><span style="color: #008000;">表示使用class=main的标签内若有p标签，执行此样式</span><span style="color: #008000;">*/</span>
<span style="color: #008080;">23</span> {
<span style="color: #008080;">24</span> <span style="color: #ff0000;">    width</span>:<span style="color: #0000ff;">400px</span>;
<span style="color: #008080;">25</span> <span style="color: #ff0000;">    font-size</span>:<span style="color: #0000ff;">36px</span>;}
<span style="color: #008080;">26</span> <span style="color: #800000;">#main</span><span style="color: #008000;">/*</span><span style="color: #008000;">以#开头，使用id选择器引用此样式表</span><span style="color: #008000;">*/</span>
<span style="color: #008080;">27</span> {
<span style="color: #008080;">28</span> <span style="color: #ff0000;">    height</span>:<span style="color: #0000ff;">60px</span>;
<span style="color: #008080;">29</span> <span style="color: #ff0000;">    width</span>:<span style="color: #0000ff;">500px</span>;
<span style="color: #008080;">30</span> <span style="color: #ff0000;">    background-color</span>:<span style="color: #0000ff;">#60C</span>;
<span style="color: #008080;">31</span> <span style="color: #ff0000;">    font-size</span>:<span style="color: #0000ff;">36px</span>;}

View Code

html file code:

<span style="color: #008080;"> 1</span> <span style="color: #0000ff;"><!</span><span style="color: #ff00ff;">DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"</span><span style="color: #0000ff;">></span>
<span style="color: #008080;"> 2</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">html </span><span style="color: #ff0000;">xmlns</span><span style="color: #0000ff;">="http://www.w3.org/1999/xhtml"</span><span style="color: #0000ff;">></span>
<span style="color: #008080;"> 3</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #008080;"> 4</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">meta </span><span style="color: #ff0000;">http-equiv</span><span style="color: #0000ff;">="Content-Type"</span><span style="color: #ff0000;"> content</span><span style="color: #0000ff;">="text/html; charset=utf-8"</span> <span style="color: #0000ff;">/></span>
<span style="color: #008080;"> 5</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>无标题文档<span style="color: #0000ff;"></</span><span style="color: #800000;">title</span><span style="color: #0000ff;">></span>
<span style="color: #008080;"> 6</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="color: #008080;"> 7</span> 
<span style="color: #008080;"> 8</span> <span style="color: #0000ff;"></</span><span style="color: #800000;">style</span><span style="color: #0000ff;">></span>
<span style="color: #008080;"> 9</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">link </span><span style="color: #ff0000;">href</span><span style="color: #0000ff;">="Untitled-1.css"</span><span style="color: #ff0000;"> rel</span><span style="color: #0000ff;">="stylesheet"</span><span style="color: #ff0000;"> type</span><span style="color: #0000ff;">="text/css"</span> <span style="color: #0000ff;">/></span>
<span style="color: #008080;">10</span> <span style="color: #0000ff;"></</span><span style="color: #800000;">head</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">11</span> 
<span style="color: #008080;">12</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">13</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">div </span><span style="color: #ff0000;">style</span><span style="color: #0000ff;">="background-color:#0F0"</span><span style="color: #0000ff;">></span>1234567<span style="color: #0000ff;"></</span><span style="color: #800000;">div</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">14</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>春天来了。<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">15</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>花儿开了，草儿绿了。<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">16</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">p </span><span style="color: #ff0000;">class</span><span style="color: #0000ff;">="sp"</span><span style="color: #0000ff;">></span>鹅鹅鹅，曲项向天歌。<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">17</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">span </span><span style="color: #ff0000;">class</span><span style="color: #0000ff;">="main"</span><span style="color: #0000ff;">></span>锄禾日当午<span style="color: #0000ff;"><</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>汗滴禾下土<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">18</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">p </span><span style="color: #ff0000;">class</span><span style="color: #0000ff;">="main"</span><span style="color: #0000ff;">></span>白日依山尽<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">19</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">p </span><span style="color: #ff0000;">id</span><span style="color: #0000ff;">="main"</span> <span style="color: #0000ff;">></span>床前明月光<span style="color: #0000ff;"></</span><span style="color: #800000;">p</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">20</span> <span style="color: #0000ff;"><</span><span style="color: #800000;">span</span><span style="color: #0000ff;">></span>疑是地上霜<span style="color: #0000ff;"></</span><span style="color: #800000;">span</span><span style="color: #0000ff;">><</span><span style="color: #800000;">br </span><span style="color: #0000ff;">/></span>
<span style="color: #008080;">21</span> <span style="color: #0000ff;"></</span><span style="color: #800000;">body</span><span style="color: #0000ff;">></span>
<span style="color: #008080;">22</span> <span style="color: #0000ff;"></</span><span style="color: #800000;">html</span><span style="color: #0000ff;">></span>

View Code

The running effect shows:

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn