# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

## Project Overview

This is a collection of small independant apps that help with the rules for Pathfinder 2E (Remastered).

## Architecture

Everything lives in `perception.html`: styles, markup, and JavaScript are co-located in one file. There are no external dependencies except Mermaid.js loaded from CDN.

### Key structural areas in `perception.html`

- **CSS custom properties** (`--bg`, `--surface`, `--border`, `--accent`, per-state color triplets `--c-<state>`, `--c-<state>-hi`, `--c-<state>-border`) drive the entire dark-fantasy color theme. Detection state colors: observed (green), hidden (amber), undetected (orange), unnoticed (red), concealed (blue), invisible (purple).

- **Tab system** (`#stealth`, `#detection`, `#simulator`): three `<div class="tab-panel">` elements toggled by `showTab()`. The Situation Simulator is the default active tab.

- **Sidebar** (`<aside id="sidebar">`): contains Detection Conditions reference cards. Hidden by default (`width: 0`), slides open with `.open` class via CSS transition. On mobile (≤640px) it becomes a fixed overlay with a backdrop (`#sidebar-overlay`).

- **Mermaid diagrams**: Two flowcharts defined as raw text inside `<div class="mermaid">` elements, rendered programmatically on `DOMContentLoaded` via `mermaid.render()`. The stealth diagram (`#stealth-diagram`) is LR-oriented; the detection diagram (`#detection-diagram`) is TD-oriented.

- **Situation Simulator**: A client-side state machine driven by two data objects:
  - `SIM_STATES` — maps state keys (`OBSERVED`, `HIDDEN`, `UNDETECTED`, `UNNOTICED`) to display labels, CSS classes, and effect descriptions.
  - `SIM_ACTIONS` — maps state keys to arrays of possible actions, each with optional roll outcomes that transition to a new state.
  - State is held in `simCurrentState` and `simHistory`. `simSetState()` resets; `simSelectAction()` handles immediate or roll-based transitions; `simSelectOutcome()` resolves roll outcomes.

## Resources

- `resources/rules/all.md` and `resources/rules/all.pdf` should be ignored due to size
- `resources/rules/condensed.pdf` contains a condensed version of the rules
- `resources/rules/perception.pdf` contains rules just for perception and detection
- `resources/rules/dying.pdf` contains rules for hit points, healing, and dying