我是 CSS 的初学者，我对这个 2 ...谁能解释我背景附件：固定和位置：固定???有什么区别
<!DOCTYPE html>
<html>
<head>
<style>
body {
background-image: url('w3css.gif');
background-repeat: no-repeat;
background-attachment: fixed;
}
p{
position: fixed;
color:Red;
}
</style>
</head>
<body>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>The background-image is fixed. Try to scroll down the page.</p>
<p>If you do not see any scrollbars, try to resize the browser window.</p>
</body>
</html>背景附件：固定用于定位图像，其中 as ， 位置 ：fixed; 用于 p ，span ，div 等元素。