overrideredirect

#! /usr/bin/env tclsh

package require Tk
wm title . Hello
wm overrideredirect . true
canvas  .cv -width 410 -height 200  -bg white
.cv create rect 0 0 360 100 -outline #c0c0c0 -fill #ffec73 -tag theRect
pack .cv
bind .cv <Enter> {
    .cv itemconfigure theRect -outline #e0e0e0 -fill #0000ff
}
bind .cv <Leave> {
    .cv itemconfigure theRect -outline #c0c0c0 -fill #ffec73
}
label .t -text "Hello world" -bg red -font {Helvetica -40 bold}
pack .t