Learn Dutch: De marge rechtsboven is te breed. - The margin top right is too wide.

In Dutch compound locative adverbs, the horizontal direction (links or rechts) always comes before the vertical direction (boven or onder). This is the exact opposite of English, which typically says "top right" or "bottom left".

Why is rechtsboven placed after De marge rather than before it?

Because rechtsboven is an adverb of place, not an adjective. In Dutch, when you use a place adverb to modify a specific noun, it must be placed directly after that noun. You cannot put it in front of the noun like an adjective; saying De rechtsboven marge is grammatically incorrect.

How would I refer to the other three corners using this exact same pattern?

You just apply the same horizontal-first rule and combine the words into a single compound. The other corners are linksboven (top left), linksonder (bottom left), and rechtsonder (bottom right).

Why does the sentence use breed for "wide" instead of wijd?

breed is used for the physical, flat, two-dimensional width of surfaces, such as paper margins, streets, or screens. wijd implies volume, spaciousness, or looseness, and is mostly used for clothing (like baggy pants) or things spread wide open (like a door).