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How does applying Z gate to |0>$|0\rangle$ change the phase of other states during reflection about |s>$|s\rangle$ in Grover algorithm in qiskitQiskit textbook

I am trying to understand the Reflection Gate - Us explained for 2 qubits in the qiskit textbook. In the explanation it is mentioned that first Hadamard gate is applied to change the state |s>$|s\rangle$ to |0>$|0\rangle$ then a circuit adds negative phase to all the states orthogonal to |s>$|s\rangle$ and this is done by applying 2 Z$Z$ (one each on both the qubits)gates gates followed by a controlled Z$Z$. I am confused about this because once |s>$|s\rangle$ goes to |0>$|0\rangle$ there won't be any superposition so Z$Z$ gates won't do anything at all because the effect of Z$Z$ gates on computational basis is to change |1>$|1\rangle$ to -|1>$-|1\rangle$. Can someone please explain. This question is different from other questions asked so please do not link it to other questions.

How does applying Z gate to |0> change the phase of other states during reflection about |s> in Grover algorithm in qiskit textbook

I am trying to understand the Reflection Gate - Us explained for 2 qubits in the qiskit textbook. In the explanation it is mentioned that first Hadamard gate is applied to change the state |s> to |0> then a circuit adds negative phase to all the states orthogonal to |s> and this is done by applying 2 Z (one each on both the qubits)gates followed by a controlled Z. I am confused about this because once |s> goes to |0> there won't be any superposition so Z gates won't do anything at all because the effect of Z gates on computational basis is to change |1> to -|1>. Can someone please explain. This question is different from other questions asked so please do not link it to other questions.

How does applying Z gate to $|0\rangle$ change the phase of other states during reflection about $|s\rangle$ in Grover algorithm in Qiskit textbook

I am trying to understand the Reflection Gate - Us explained for 2 qubits in the qiskit textbook. In the explanation it is mentioned that first Hadamard gate is applied to change the state $|s\rangle$ to $|0\rangle$ then a circuit adds negative phase to all the states orthogonal to $|s\rangle$ and this is done by applying 2 $Z$ (one each on both the qubits) gates followed by a controlled $Z$. I am confused about this because once $|s\rangle$ goes to $|0\rangle$ there won't be any superposition so $Z$ gates won't do anything at all because the effect of $Z$ gates on computational basis is to change $|1\rangle$ to $-|1\rangle$. Can someone please explain. This question is different from other questions asked so please do not link it to other questions.

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How does applying Z gate to |0> change the phase of other states during reflection about |s> in Grover algorithm in qiskit textbook

I am trying to understand the Reflection Gate - Us explained for 2 qubits in the qiskit textbook. In the explanation it is mentioned that first Hadamard gate is applied to change the state |s> to |0> then a circuit adds negative phase to all the states orthogonal to |s> and this is done by applying 2 Z (one each on both the qubits)gates followed by a controlled Z. I am confused about this because once |s> goes to |0> there won't be any superposition so Z gates won't do anything at all because the effect of Z gates on computational basis is to change |1> to -|1>. Can someone please explain. This question is different from other questions asked so please do not link it to other questions.