Improve "smoothness"

themes/microdeck/bottom-active.xpm

themes/microdeck/bottom-inactive.xpm

themes/microdeck/bottom-left-active.xpm

themes/microdeck/bottom-left-inactive.xpm

themes/microdeck/bottom-right-active.xpm

themes/microdeck/bottom-right-inactive.xpm

themes/microdeck/left-active.xpm

themes/microdeck/left-inactive.xpm

themes/microdeck/right-active.xpm

themes/microdeck/right-inactive.xpm

themes/microdeck/title-1-active.xpm

themes/microdeck/title-1-inactive.xpm

themes/microdeck/title-2-active.xpm

themes/microdeck/title-2-inactive.xpm

themes/microdeck/title-3-active.xpm

themes/microdeck/title-3-inactive.xpm

themes/microdeck/title-4-active.xpm

themes/microdeck/title-4-inactive.xpm

themes/microdeck/title-5-active.xpm

themes/microdeck/title-5-inactive.xpm