Pressed g + z but selection still won't move on z axis

Hello all, trying to animate the legs.
I can’t seem to be able to angle the middle leg downward.
even when selecting g + Z it rotates but doesn’t go downward.
not quite sure what I am doing wrong


Remember that bone has its own local coordinate system. Bones Y-axis always points along the length of bone. So when posing, you should have the transform orientation set to “Local”. And,display the bone axis. So you know which axis to rotate.

thank you. will go check for that