Phase portrait of $u_{xx} + u(1-u)(u-0.5)$?

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I was considering this PDE $u_{t} = u_{xx} + u(1-u)(u-0.5)$; $0 \leq x \leq L$ with boundary condition $u_{x}(0,t) =0 ; u_{x}(L,t) =0$.

For the steady state we need $u_{t} = 0$ implying $u_{xx} + u(1-u)(u-0.5) = 0$.

I was trying to understand the phase portrait of the system: Let $v = u_{x}$, then $v_{x} + u(1-u)(u-0.5) = 0$ so we have two dimensional system :

$v_{x} = -u(1-u)(u-0.5) = f(u,v)$

$u_{x} = v = g(u,v)$

The fixed points of the system are $(u^*,v^*) = (0,0) ; (0.5,0) ; (1,0)$ in which $(1,0)$ is stable and the other two are unstable fixed points.

I am thinking of drawing the phase portrait, like i tried the online tool but seems that does not satisfy the boundary condition $v(0) = 0, v(L) = 0$. enter image description here

I am not sure about the phase portrait of the system and to see the boundary conditions in the picture.