1. What is DeckZenith?

DeckZenith is a minimalist, ultra-responsive spaced-repetition cognitive system powered by Hono + Cloudflare D1. All progress is automatically stored in high-speed cloud tables without requiring annoying passwords or registrations.

2. Study Modes

• Endless: Continuous reinforcement loop with spaced interval promotion.
• Block Test: Strict batch examination of due cards with error relearning.
• Self-Assessment: Classic flashcard flip to check mental recall honesty.
• Active Typing: Full neuro-motor retention practice by entering terms.
• Survival: High-stakes time-attack where correct answers add time.
• Pair Matching: Fast perceptual recognition board game.
• N-Back Workout: Dual task working memory expander with real-time brain age estimation.

3. Cloud Synchronization (Multi-Device)

Your browser is issued a private Cloud Vault Key on your first visit. To use the exact same decks on your smartphone or another computer, tap COPY KEY on this device, then tap SYNC DEVICE on your other device and paste it. No passwords required.

4. Interactive Drawing Canvas

During study sessions, expand the canvas under ✍️ Pen to write kanji, sketch diagrams, or take rapid notes. Touch-drawing and mouse-pen are fully supported.

5. Keyboard Shortcuts

• 1, 2, 3, 4: Select corresponding choice option.
• Space: Show answer in Flashcard mode, or advance to next question.
• Enter: Submit typed answers.