🎵 Notes fall from the top — hit the lane key as one reaches the judgment line
⌨️ Four lanes → D F J K (or tap the screen)
📏 Hold notes: keep the key down until the tail passes the line
🎹 Chord notes: two lanes light up at once — hit both together
🎯 Grades: PERFECT / GREAT / GOOD / MISS
🔥 FEVER: fill the gauge with clean hits to trigger 2× scoring
🏆 Clear with no Miss for a FULL COMBO; all PERFECT for ALL PERFECT
❤️ A Miss costs health; run out and it's game over · Esc pauses

Higher speed = notes fall faster. Positive offset if you hit consistently early (FAST).