Tab Margins

Docking Pane allows you to manipulate the margins of the components that make up the tabs.  You can change the button, header, client, and control margins of the tabs.  The button margin is the area in the tab button surrounding the tab caption, the header margin is the area surrounding the tab buttons, the client margin is the area surrounding the client (area inside the tabs), and the control margin is the area surrounding all of the tabs and tab client area.