Playground

Turn a knob, watch the page change. Each block generates a small template from the control values and renders it with the engine in your tab — the YAML you see is exactly what rendered.

Text style

textAlign, fontSize, lineHeight, letterSpacing. The box height is computed from fontSize × lineHeight — the reference's rule that a fixed-height box below that product raises text_overflow is one you can verify with the slider.

Layout: columns from omission

The flex row's rule: children WITHOUT a width split the leftover equally. Three columns is not a property — it is three children that each declined to claim one. Slide the count and the gap.

Fonts

Fonts are packs, and a fontFamily may only name a face from a pack the active locale uses — under ja-JP that is BIZ UDP Gothic and Noto Sans Mono here. The Japanese line keeps the locale's default family; the knob swaps the Latin specimen. Adding your own font is the same mechanism: one pack directory, one uses line (see the tutorials).

Character grids and vertical writing

The manuscript-paper char_grid. writingMode is an item-level key, not a style property; vertical_rl turns lines into right-to-left columns. Cell size is grid.cellSize.

The full story

The complete property list lives in the reference — one page per feature. This page holds only the properties whose behavior travels faster as motion than as words.