Hello, can you please tell me how can I move the green edges along the selected edges? In this case, the ribs can be at different “levels”. In general, so that the edges go along the edges like on rails.
Not very clear in what you want to do…But here is what I think you are asking for…
Assuming that the origin is 000 and that is 1 object…this is what will give you that effect…
Select all the white inside faces and separate them by selection…
now both objects have the same origin, again assuming it is flat on the x and y-axis ie. not rotated…then entering S > “scale” + Shift Z will pull the green areas into the center following along the edges you have selected ( shift +z stops the scalling in the Z-axis)
You could try extruding along normals
try selecting the edges at the end, SNAP 3d crusor to selection.
select the to-be moved parts and SNAP to 3d cruser.
just keep in mind angels of the original parts before moving
Do you mean you just want to move the edge loops down closer to the lower outside edge? In Edit Mode, press 1 to go to Vertex mode, then Option/Alt-Select the edge loop that you want to move (Shift-Alt-LMB to select the second one), then press GG and slide them down.
Disclaimer: This is a stupid answer but I think it is what you want to do.
If you want to slide the green area on those edges and conserve the “bump” I think you can not do it easily. Edge slide will not give you the result you want. I could be wrong maybe there is a way of doing it.
As I do not like saying “it’s impossible” I made a simple armature with envelope weights, placing the bones on the edges. For the parent bones (the ones I have selected in pose mode) I killed the envelope weights, their children do not inherit scale. Then I key-framed the scale of the parents.
I did warn it was a silly answer 
If the object is a ring, then DNorman you’re right, Edge Slide won’t work. In that case, Sorda, maybe you can just delete the original edge loops that are in the wrong place, the select the outside edge loop and use Ctrl-Shift-R to create new edge loops in parallel to the outside edges, where you want them.
