Tutorial

Step indices are hardcoded in all four files. When inserting or removing a step, update every reference:

1. useTutorial.ts — add/remove entry in TUTORIAL_STEPS[], update all case numbers in useIsStepSatisfied()
2. TutorialOverlay.tsx — update these step sets to match new indices:
   • STEPS_REQUIRING_PANEL_OPEN — steps that need the options panel open
   • STEPS_IN_NAVBAR — steps targeting navbar elements
   • SETTINGS_STEPS — steps that show the settings modal
3. TutorialOverlay.tsx — update step !== N checks in every step-specific useEffect hook (tab cycling, split mode setup, reactant selection, etc.)
4. Dashboard.tsx — update the tutorialStep >= N && tutorialStep <= M range for settings steps

Checklist after any step change:

• TUTORIAL_STEPS[] array updated
• useIsStepSatisfied() cases renumbered
• Step sets (STEPS_REQUIRING_PANEL_OPEN, STEPS_IN_NAVBAR, SETTINGS_STEPS) updated
• Step-specific useEffect hooks reference correct step numbers
• Dashboard.tsx settings step range updated
• Comments on effects match their new step numbers
• Run npx tsc --noEmit and npx vitest run

Tutorial Highlight CSS

Highlights are applied by adding the tutorial-highlight class to the target element via its targetId.

Key rules:

1. Always use background fill, not just outline. Outline alone is too subtle — users won't notice it. Use background: var(--color-primary-light) for light-background elements.

2. Navbar elements need inverted highlights. The navbar has a dark background, so --color-primary-light makes text unreadable. Use background: rgba(255, 255, 255, 0.2) instead. The .navbar .tutorial-highlight rule handles this.

3. Don't add extra padding to highlighted elements. It shifts layout and the user will reject it. Use outline-offset and matching box-shadow spread to extend the highlight area without affecting layout.

4. Match box-shadow spread to outline-offset. If outline-offset: 3px, use box-shadow: 0 0 0 3px. Mismatched values look wrong.

5. Check for inline styles before adding CSS. Some elements (e.g., .filter-panel) have inline styles in their component that override CSS. If your CSS change has no effect, check the component's JSX for inline style={}.

Highlight style by element type:

Plotly Integration (Zoom Reset)

• Never use key-based remount to reset Plotly zoom. Plotly mutates layout objects in place — remounting reuses the mutated layout with zoom ranges baked in, causing data loss.
• Use Plotly.relayout() to reset zoom: Plotly.relayout(div, { 'xaxis.autorange': true, 'yaxis.autorange': true })
• Plotly uses its own event emitter, not DOM events. addEventListener('plotly_relayout', ...) does NOT work. Use the onInitialized callback from react-plotly.js to get the graph div, then register via graphDiv.on('plotly_relayout', handler).
• The useZoomReset() hook in DistributionView.tsx encapsulates this pattern — reuse it in any new plot component.