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<!DOCTYPE html>
<html>

<body style="background: #f3f3f3 url('img_tree.png') no-repeat fixed right top;">
<h1>HTML Style Object</h1>
<h2>The backgroundAttachment Property</h2>

Tip: Try to to resize the window if the scrollbar is not available.
Click the button to toggle between scroll and fixed position.
Tip: Scroll the page before and after you have clicked the button.

<button id="toggle" onclick="myFunction();">Set image to scroll</button>
 

Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.
 
Some text to enable scrolling.

</body>
</html>

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<!DOCTYPE html><html>​<body style="background: #f3f3f3 url('img_tree.png') no-repeat fixed right top;"><h1>HTML Style Object</h1><h2>The backgroundAttachment Property</h2>​<p><b>Tip:</b> Try to to resize the window if the scrollbar is not available.</p><p>Click the button to toggle between scroll and fixed position.</p><p><b>Tip:</b> Scroll the page before and after you have clicked the button.</p>​<button id="toggle" onclick="myFunction();">Set image to scroll</button> <p>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br>Some text to enable scrolling.<br><br><br><br></p>​<script>function myFunction() {  let x = document.body.style.backgroundAttachment;  document.getElementById("toggle").innerHTML=(x=="scroll")? "Set bg image to scroll!":"Set bg image to fixed!";