# User Guide

## Getting Started

Open the homepage and browse modules by category or use the search bar.

## Using a Module

1. Select a module from the sidebar or homepage grid.
2. Fill in the required inputs (validated in real time).
3. Click **Calculate** to see results, interpretation, and charts.
4. Use toolbar buttons to **Export**, **Print**, **Copy**, or **Reset**.

## Features

### Bookmarks
Click the star icon on any module to save it. Bookmarked modules appear in the sidebar.

### History
Recent modules appear in the sidebar under "Recent". Click to revisit.

### Themes
Toggle dark/light mode with the moon/sun icon in the header. Your preference is saved.

### Search
Type in the search bar to find modules by name, description, or category.

### Export
Most modules support exporting results as:
- **PDF** — via jsPDF + html2canvas
- **CSV** — via PapaParse
- **JSON** — raw data export
- **PNG** — chart/image export

### Print
Click the print button for a print-friendly layout.

### Offline
Once loaded, the site works without internet (Service Worker).

## Keyboard Shortcuts

| Key | Action |
|-----|--------|
| `/` | Focus search |
| `Esc` | Close modal / clear search |
| `Tab` | Navigate forward |
| `Shift+Tab` | Navigate backward |
| `Enter` | Activate focused element |

## Data Privacy

All data stays in your browser. Nothing is sent to external servers except API calls you explicitly trigger.