# Manually calculating quantum circuit with custom gate

I am trying to calculate the state of this Quirk circuit by hand:

where U is a custom gate with 2x2 matrix:

From what I've read, I should be able to calculate the resultant amplitudes as:

(U⊗I⊗I).(anti_controlled_H⊗I).(anti_Toffoli)

which is

But the resulting amplitudes in Wolfram Alpha do not match the Quirk output, leading me to believe I've made fundamental mistake. What am I missing?

That is, a quantum circuit contains the gate $$U_1$$ followed by $$U_2$$ is equivalent to $$U_2U_1$$.
Which means you need to calculate $$(\text{Anti-CCX})(\text{Anti-CH} \otimes I)(U \otimes I \otimes I)$$