CSS的background-origin属性
Background-origin属性指定背景图像的位置。
注意:如果background-attachment属性设置为fixed，则此属性不起作用。
默认值:padding-box
可能值：
padding-box-该位置是相对于填充框的
border-box-该位置相对于边框框
content-box-位置相对于内容框
initial
inherit
CSS
.example {
width: 300px;
border: 20px solid black;
padding: 50px;
background: url(https://static.pexels.com/photos/6440/magazines-desk-work-workspace-medium.jpg);
background-repeat: no-repeat;
}
.example1 {}
.example2 { background-origin: border-box; }
.example3 { background-origin: content-box; }
HTML
<p>No background-origin (padding-box is default):</p>
<div class="example example1">
<h2>Lorem Ipsum Dolor</h2>
<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.</p>
<p>Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat.</p>
</div>
<p>background-origin: border-box:</p>
<div class="example example2">
<h2>Lorem Ipsum Dolor</h2>
<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.</p>
<p>Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat.</p>
</div>
<p>background-origin: content-box:</p>
<div class="example example3">
<h2>Lorem Ipsum Dolor</h2>
<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.</p>
<p>Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat.</p>
</div>