v0.28.1

App::spawn_root() creates the root widget, applies a default
fill-viewport style (grow: Fixed::ONE, ColorToken::Surface,
FlexDirection::Column), and registers it via set_root in one call,
returning a RootBuilder whose chainable .bg_color() / .layout()
override the defaults. Gallery demo bodies no longer patch the
caller-supplied parent's Style — root styling now lives at the spawn
site.

The web gallery builds and serves with trunk:
a <link data-trunk rel="rust"> plus Trunk.toml replace the manual
wasm-bindgen + python -m http.server steps, and register_demos!
generates the sidebar and routes from one table covering all 46 demos.

Added

• App::spawn_root() -> RootBuilder — spawns the root, applies a default fill-viewport style, and registers it via set_root. RootBuilder chains .bg_color() / .layout() to override defaults; .id() finalizes. Available on no_std.

Changed

• Gallery demo bodies — build_widgets no longer sets the root's Style; callers obtain a styled root from App::spawn_root(). Demos that previously hand-built children with WidgetBuilder + manual Parent/Children wiring (app_demo, click, rounded, text, image) are rewritten as pure ui! trees.

Fixed

• Button releases Tap / DragEnd to user handlers — button's internal gesture handler returned true on Tap/DragEnd, which stopped bubble dispatch and prevented a user-attached GestureHandler from ever firing. It now returns false so user handlers run; the pressed state toggle and Dirty insert still happen.
• web-canvas no longer panics on offscreen effects — WebCanvasRenderer now overrides sample_target_region / modify_target_region to return None / false instead of inheriting the default unimplemented!() panic. BackgroundBlur / MirrorOf / TemporalMix degrade gracefully on the web backend rather than freezing the frame loop.

Internal

• gallery-web migrated to trunk: index.html carries data-trunk rel="rust" with --all-features wired into data-wasm-opt-params (rustc emits bulk-memory ops for wasm32 that binaryen validates against only when told). Trunk.toml pins dist/serve/watch. cargo xtask wasm-build shells out to trunk build --release; new cargo xtask web-serve runs trunk serve.
• register_demos! macro in gallery/src/lib.rs emits a DEMOS table (slug / label / category / size / setup fn) plus lookup_demo and a wasm-bindgen nav_html(); the web sidebar groups all 46 demos by category.