HTML Playground

Paste HTML with inline styles; outlay parses it with parseHTML, lays it out off-DOM with solveLayout, and draws the boxes on the left — checked live against the real browser on the right. The parser is strict on purpose: anything outside its supported vocabulary throws with the exact path to the offending element, so the error state is a feature, not a failure.

Every container spells out display: an absent display maps to outlay's flex default, whereas the injected browser markup would default to block — so the presets declare it to keep the comparison honest.