Make quote button more css-independent

boards/static/js/thread.js

@@ -110,7 +110,7 b' function showQuoteButton() {'
     var selection = window.getSelection().getRangeAt(0).getBoundingClientRect();
     if (selection.width > 0) {
         // quoteButton.offset({ top: selection.top - selection.height, left: selection.left });
-        $quoteButton.css({top: selection.top + $(window).scrollTop() - 30, left: selection.left});
+        $quoteButton.css({top: selection.top + $(window).scrollTop() - parseInt($quoteButton.css("height"), 10) - 3, left: selection.left});
         $quoteButton.show();
 
         var text = window.getSelection().toString();