{{-- OUTER FLEX CONTAINER — sidebar + main sit side-by-side in the flex row --}}
{{-- flex:1 means this takes ALL remaining width after the sidebar --}}
{{-- min-width:0 prevents horizontal overflow; overflow:hidden clips the column bounds --}}
{{-- On desktop → toggles collapse (icon mode). On mobile → toggles drawer. --}}
{{-- min-height:0 is THE critical fix: without it flex children won't shrink below
their content size, so overflow-y:auto never activates and content is un-scrollable --}}