# Concentric circles
handle: name $x+w/2$ $y-4$ middle
<circle cx="$x+w/2$" cy="$y+h/2$" r="$w/2$" fill="#AFEEEE"/>
<circle cx="$x+w/2$" cy="$y+h/2$" r="$w/2.5$" fill="#87CEFA"/>
<circle cx="$x+w/2$" cy="$y+h/2$" r="$w/4$" fill="blue"/>
<circle cx="$x+w/2$" cy="$y+h/2$" r="$w/6$" fill="darkblue"/>
<line x1="$x+w/2$" y1="$y$" x2="$x+w/2$" y2="$y+h$"  fill="none" stroke="black" stroke-width="1"/>
<line x1="$x$" y1="$y+h/2$" x2="$x+w$" y2="$y+h/2$"  fill="none" stroke="black" stroke-width="1"/>
<line x1="$x$" y1="$y$" x2="$x+w$" y2="$y+h$"  fill="none" stroke="black" stroke-width="1"/>
<line x1="$x$" y1="$y+h$" x2="$x+w$" y2="$y$"  fill="none" stroke="black" stroke-width="1"/>