CSS: Background image and padding
You can be more precise with CSS background-origin:
background-origin: content-box;
This will make image respect the padding of the box.
You can use percent values:
background: yellow url("arrow1.gif") no-repeat 95% 50%;
Not pixel perfect, but…
Use CSS background-clip:
background-clip: content-box;
The background will be painted within the content box.