These proportions look a bit like the organic periodic table.
So from the start of the green line to the right is 1080 x 2.5= 2700
This will be the width and 540 will be the height.
540 / 40 = 13.5
67.5 x 2 = 135
1080 / 40 = 27
Here is another way of looking at things.
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