2nd test -
Outer Column has different padding on mobile: 16 0 16 16 (because right pad is creating the final gutter).
Inner Columns all same. Inner Sections have right padding (for the gutter) 32 on desktop; 16 on mobile.
1st IS has 68px additional left padding.
Final IS has 68px right padding.
Inner Sections do not need width or max-width. Inner Columns are fixed at 508px Custom Width (breaking bad).