CSS 设计模式一 元素

1、background  内置

是一种CSS内置设计模式,支持在元素下显示图片

HTML

<!DOCTYPE html>

<html lang="en">

      <head><title>Background Image</title>

        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

        <link rel="stylesheet" href="site.css"   media="all"    type="text/css" />

        <link rel="stylesheet" href="page.css"   media="all"    type="text/css" />

        <link rel="stylesheet" href="print.css"  media="print"  type="text/css" />

        <!--[if lte IE 6]>

        <link rel="stylesheet" href="ie6.css"    media="all"    type="text/css" />

         <![endif]-->

      </head>

       <body>

       <h1>Background Image</h1>

       <div></div>

     </body>

</html>

CSS

div { background:url("heading2.jpg") no-repeat; 250px; height:76px; }

2、Absolute  绝对定位

是将元素从流中移除,然后将它相对于另一个元素进行重新定位。

HTML

<!DOCTYPE html>

<html lang="en">

      <head><title>Absolute</title>

     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

     <link rel="stylesheet" href="site.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="page.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="print.css"  media="print"  type="text/css" />

     <!--[if lte IE 6]>

     <link rel="stylesheet" href="ie6.css"    media="all"    type="text/css" />

     <![endif]-->

      </head>

       <body>    

         <h1>Absolute</h1>

         <div class="positioned">

              <span class = "absolute">Sized Absolute</span>

         </div>

     </body>

</html>

CSS

/* Non-essential styles */

*.positioned { height:120px; border:2px solid black; }

*.absolute   { padding:5px; text-align:center;

               border:5px solid black; background-color:gold; }

/* Essential Styles */

*.positioned { position:relative; }

*.absolute   { position:absolute; top:10px; left:10px; }

3、Text Replacement 文本替换

是将一些文本的位置上显示一张图片。当图片下载失败时,则显示文本信息。

HTML

<!DOCTYPE html>

<html lang="en">

     <head>

           <title>Text Replacement</title>

     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

     <link rel="stylesheet" href="site.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="page.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="print.css"  media="print"  type="text/css" />

     <!--[if lte IE 6]>

     <link rel="stylesheet" href="ie6.css"    media="all"    type="text/css" />

     <![endif]-->

      </head>

       <body>    

          <h1>Text Replacement</h1>

          <h2 id="h2">Heading 2 <span></span></h2>

      </body>

</html>

CSS

#h2      { position:relative; 250px; height:76px; overflow:hidden; }

#h2 span { position:absolute; 250px; height:76px; left:0; top:0;

           background:url("heading2.jpg") no-repeat; }

4、Left Marginal 左旁注

是将一个或多个元素移动到块级元素的左边。

HTML

<!DOCTYPE html>

<html lang="en">

     <head>

     <title>Left Marginal</title>

     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

     <link rel="stylesheet" href="site.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="page.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="print.css"  media="print"  type="text/css" />

     <!--[if lte IE 6]>

     <link rel="stylesheet" href="ie6.css"    media="all"    type="text/css" />

     <![endif]-->

     </head>

     <body>    

         <h1>Left Marginal</h1>

              <div class="left-marginal">

                    <h2 class="marginal-heading">Heading</h2>

                   You want to except an element and move it into the left margin.

               </div>

     </body>

</html>

CSS

 *.left-marginal { position:relative;margin-left:200px;}

 *.marginal-heading { position:absolute;left:-200px;top:0px;margin:0px;}

5、Marginal Graphic Dropcap 旁注图片下沉

是将一个或多个元素移动到块级元素的左边。

HTML

<!DOCTYPE html>

<html lang="en">

     <head>

     <title>Left Marginal</title>

     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

     <link rel="stylesheet" href="site.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="page.css"   media="all"    type="text/css" />

     <link rel="stylesheet" href="print.css"  media="print"  type="text/css" />

     <!--[if lte IE 6]>

     <link rel="stylesheet" href="ie6.css"    media="all"    type="text/css" />

     <![endif]-->

     </head>

    <body>

        <h1>Marginal Graphic Dropcap</h1>

        <p class="indent">

                <span class="graphic-dropcap">

                 M

                <span></span>

        </span>

        arginal Graphic Dropcap.The letter M has been covered by the dropcap image.

        Screen readers read the text and visual users see the image.

        If the browser cannot display the dropcap image,

        the text becomes visible.

            </p>

         </body>

</html>

CSS

 *.indent {

            position: relative;margin-left: 120px;

  } 祖元素

 *.graphic-dropcap{

       position: absolute;120px;height:90px;left:-120px;top:0px;

 }

          

 *.graphic-dropcap span { position:absolute;120px;height:90px;margin:0px;left:0px;top:0px;

                            background:url("m.jpg") no-repeat;

 }

原文地址:https://www.cnblogs.com/zorro8z8/p/3543740.html