Animation problem (dash line is turned into solid line )

I combined two animations as follow, but the dash line is turned into solid line. How can I solve this?

with(plots);

A := animate([X, X+t, X = -10 .. 10], t = -10 .. 10, color = red, linestyle = dash);

B := animate([X, t^2+X, X = -10 .. 10], t = -10 .. 10, color = blue, linestyle = solid);

display([A, B]);