A Single Page Application (SPA) designed to train mental arithmetic skills. Built with a focus on speed, precision, and progress tracking using standard speedcubing metrics (Ao5, Ao12).

• Basic Operations: Multiplication, Addition, Subtraction, and Division.
• Mixed Mode: Randomizes all operations to train mental flexibility.
• ⚡ Chain Math (Flash Anzan): A standout feature that flashes a sequence of numbers rapidly to train working memory alongside calculation skills.

Going beyond simple scores, this app uses advanced statistical metrics to measure consistency:

• Ao5 (Average of 5): Rolling average of the last 5 sessions (excluding the fastest & slowest times).
• Ao12 (Average of 12): Rolling average of the last 12 sessions for medium-term performance tracking.
• Accuracy Graphs: Visualizes percentage of correct answers per operation.
• Error Analysis: A history log of wrong answers to help review specific weaknesses.

• Power Table ($x^n$): A dynamic exponentiation table utilizing BigInt for high-precision large number rendering.
• Multiplication Table: A standard 1-40 multiplication grid for quick reference.

• "Fresh Pastel" Theme: A color palette designed to be easy on the eyes, reducing visual fatigue during long training sessions.
• Non-Intrusive Input: Auto-focus on input fields and full keyboard navigation support (Enter to submit).
• Responsive: Layout automatically adjusts for both Desktop and Mobile experiences.

This project is built using a Pure Vanilla JavaScript approach for maximum performance with zero framework overhead.

• Frontend: HTML5 (Semantic), CSS3 (Variables, Flexbox, Grid).
• Logic: JavaScript ES6+ (Centralized State Management).
• Persistence: LocalStorage API (Locally saves session history and user settings).
• Timing: performance.now() for millisecond-precision timing.

mental-math-trainer/
│
├── index.html      # Main Entry Point (SPA Structure)
├── styles.css      # Styling with CSS Variables & Responsive Design
├── app.js          # Application Logic (State, Math Logic, UI Rendering)
└── README.md       # Project Documentation