The html code for the widget header is as follows.
<div class="widget-header">
<span>caption</span>
<a href="sh/index.php?type=rec">more</a>
<img src="/img/widgets/widgets_more.gif" />
</div>
My CSS code is
.widget-header span { float: left; }
.widget-header a, img { float: right; }
If this, the widgets_more right arrow would position to the left of text ‘more’ like this,

How can I get the right order with modifying the css code?
Thanks.
Instead of placing the arrow next to the link as an image, you should set it as a background image in a class.
Something like this should do it (untested but should work):
CSS:
If you want the link to appear on the left of the link, then use the following:
Then apply the class to your link:
Also, the element floated to the right should be stacked above the element floated to the left. So rearrange your HTML to look like this: