Make the editor usable with a finger, not just reachable by one

[kmatzen]

Fixes the mobile audit findings. Stacked on #125 (the audit itself) — review that first, or read this diff against worktree-mobile-usability-audit.

Closes #126, #127, #128, #129, #130, #131, #132, #133, #134, #135, #136. Partially addresses #137.

The approach

Touch sizing is gated on @media (pointer: coarse), not on a width breakpoint. What matters is whether a fingertip is doing the pointing — a touchscreen laptop should get bigger targets, a narrow desktop window should not — and it leaves desktop density untouched by construction. .tap / .tap-h / .tap-w are opt-in per site rather than a blanket button { min-height }, because several of these buttons sit in fixed-height rows where growing the button breaks the row instead of the row growing with it.

What changed

#	Fix
126	Coarse-pointer sizing across toolbar, viewport tools, tree rows and actions, property controls, palette tabs, number input. The 18px number input is now 44px.
127	MobileEmptyState in the viewport with the two ways in as buttons — instead of a black void.
128	Two-tap move mode for reparenting, alongside the existing drag-and-drop. HTML5 DnD never fires from touch, so this was the only way to restructure a tree on a phone. Works with mouse and keyboard too.
129	16px inputs on coarse pointers; inputMode="decimal" + enterKeyHint on NumberInput (stays type="text" so 10*2+5 still parses).
130	Chat drawer gets a close button, top-11 to match the toolbar, and useKeyboardInset lifts it clear of the iOS keyboard.
131	viewport-fit=cover, safe-area helpers, 100dvh, overscroll-behavior, tap-highlight, text-size-adjust, user-select.
132	Tap slop is pointer-type aware (4px mouse / 10px touch — fingers wander 5–10px, so real taps were being discarded as orbits); gizmo scales up on coarse pointers.
133	Sheet opens at 55%, has a close button, recomputes snap points on resize/rotation.
134	Duplicate NODE TREE header removed; Escape closes both mobile containers.
135	Export resolution and share-copy confirmation reach the mobile overflow menu.
136	e2e/mobile.spec.ts + a mobile Playwright project on iPhone 13.
137	Layout switch moved 768 → 1024, so iPad portrait gets a full-width viewport and drawers instead of a ~200px column.

The test that matters

The sweep asserting nothing on screen is under 44px is deliberately not a set of per-button assertions — individual sizes get adjusted and those assertions rot, whereas a sweep fails on the next control someone adds at desktop density. It already earned its keep: it caught a 42px input, because the row's 1px border sits outside its content box so an input stretched to h-full lands two pixels short.

Verification

• npm test — 503 passed
• npx playwright test (serial, as CI runs it) — 81 passed across chromium, mobile, golden
• Re-shot on emulated iPhone 13 / iPad Mini / landscape to confirm visually

Note: running the three projects with local parallel workers produces spurious failures — the config already documents WebGL oversubscription on multi-worker runs, and adding a third project makes it worse. Serial is clean.

Deliberately not done

• Copy/paste still has no mobile control. It needs a paste-target concept that does not exist yet; worth designing rather than bolting on.
• Landscape phones still get the portrait arrangement. Toolbars wrap now so nothing overflows, but 342px of height wants its own layout. Left open in iPad portrait lands on the desktop layout with a 200px viewport; landscape phone reuses portrait #137.
• Opening the sheet at 55% covers more of the model than 33% did, and the camera does not frame against the visible area. Dragging down still works; camera-inset framing is a follow-up.

🤖 Generated with Claude Code

[kmatzen]

Reviewed this against origin/main and it's solid overall — breakpoints (md:→lg:, isMobile() 768→1024) are consistent across Toolbar/NodeTreePanel/PropertyPanel/ChatDrawer/BottomSheet/MobilePanel, viewport-fit=cover is in index.html, pb-safe/pl-safe/pr-safe are defined, useKeyboardInset cleans up its listeners with correct offset math, moveNode guards against cycles, and the BottomSheet snap-point recompute on resize looks right.

One correctness bug I'd fix before merge:

The #129 iOS-zoom fix doesn't cover three of the controls it's meant to fix

src/index.css (the @media (pointer: coarse) block):

input, select, textarea,
input[type="text"], input[type="number"], input[type="password"] {
  font-size: 16px;
}

The comment above it says this has to "beat the utility classes on the inputs themselves." The enumerated input[type="..."] selectors do have the specificity for that (0,1,1 beats a text-sm/text-[12px] Tailwind class at 0,1,0). But the bare input, select, textarea selectors are only 0,0,1 and lose to any text-* class — Tailwind isn't in important mode here. So any control that (a) has no type attribute, or (b) is a <select>, keeps its Tailwind text size and still triggers iOS Safari's zoom-on-focus.

Three always-visible mobile controls hit this:

• src/components/toolbar/Toolbar.tsx:151 — project-name <input> has no type + text-sm → stays 14px. Always on screen on mobile (not lg:hidden). This is audit §3's "Project name — 14px" item.
• src/components/chat/ChatDrawer.tsx:131 — chat composer <input> has no type + text-sm → stays 14px. Audit §3's "Chat input — 14px".
• src/components/toolbar/Toolbar.tsx:259 — export-resolution <select> + text-[12px] → stays 12px (only the bare select selector can match a <select> at all).

Only NumberInput is actually rescued, since it carries an explicit type="text".

This also looks like it would fail the PR's own new e2e/mobile.spec.ts — "text entry does not zoom the page" scans every visible input/select/textarea for font-size < 16, and the project-name input is on screen throughout that test.

Smallest fix I can see: add type="text" to the two type-less <input>s so they hit the high-specificity rule, and give the base rule enough specificity to also catch <select> — e.g. input:not([type]), input[type="text"], input[type="number"], input[type="password"], select, textarea { font-size: 16px; } — or just drop the text-sm/text-[12px] classes from these three controls.

(Minor, possibly intentional: MobileEmptyState.tsx:32 is absolute inset-0 z-10 with no pointer-events-none, so while it's shown it sits over the ViewportToolbar buttons. Flagging for awareness only, since there's no model to act on at that point anyway.)

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Generated by Claude Code

[kmatzen]

Correction to my earlier review comment: the CSS-specificity bug I reported for the project-name input, chat composer, and export <select> doesn't actually exist. I got the cascade wrong — sorry for the noise.

I analyzed the @media (pointer: coarse) { input, select, textarea, ... } rule as if it were competing with .text-sm under plain CSS specificity rules. It isn't. This project imports Tailwind v4 (@import "tailwindcss" in index.css), which expands to @layer theme, base, components, utilities; and puts every utility class — .text-sm included — inside @layer utilities. The coarse-pointer rule in index.css is not inside any @layer. Per the CSS cascade-layers spec, an unlayered rule always beats a layered one, regardless of specificity — so the existing rule already wins outright, and the specificity concern I raised doesn't apply.

I confirmed this two ways before retracting:

• Ran the PR's own e2e/mobile.spec.ts "text entry does not zoom the page" test against the unmodified branch (no fix applied) — it passes.
• Dumped getComputedStyle(...).fontSize for the project-name input directly in a real page load: 16px, not the 14px my specificity analysis predicted.

No action needed on this point — the existing rule is correct as written. The other notes in my first comment (breakpoint consistency, safe-area CSS, useKeyboardInset, etc. all checking out; the minor MobileEmptyState z-index observation) stand.

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