gif images don’t show

I have tested a template OK (running xampp on localhost) before uploading to my site. Say below CSS for a dot
#leftbar ul {
list-style-image: url(image/sideuldot.gif);
}

The dot appears OK on localhost but once uploaded doesn’t show up at my site, you could see it at https://me.sfong.net/ (try the 0.35-bb-left theme on the switcher).

I have also tried url(‘image/sideuldot.gif’) which didn’t work also.