I have made some changed to the css and uploaded the server, however, the changes aren't effective. Indeed I checked the raw source code, the line is
<LINK REL="stylesheet" TYPE="text/css" HREF="./qa-theme/Default/qa-styles.css?1.4.3">
while I expect it to be
<LINK REL="stylesheet" TYPE="text/css" HREF="./qa-theme/Default/qa-styles.css">
because I changed the later file. What's the problem then? thanks.