How to keep taskbar having rounded theme without intellihide?

Well,
I found the same concern solved already there
floating-taskbar-without-autohide

@Aravisian you're right
It works now by adding the following in .../gnome-shell.css

#panelBox { padding-bottom: 0.4em; 
            padding-left: 0.6em; 
            padding-right: 0.6em; }
#panel    { border-radius: 10px; }