Let’s talk about the solution directly:
Assume that the size of a combined large picture is: 900 x 1000 px (as shown above)
Now I want to take the hippopotamus icon in the upper left corner of the picture and reduce the size of the icon.
Normally take the image:
.sprite { background: url('imgs/woqu_localjoin_all.png') no-repeat -21px -80px; width: 190px;height: 154px;}
<pre name="code" class="html">.sprite { background: url('all.png') no-repeat -10px -40px;width: 95px;height: 74px;background-size:450px 500px;}