jump() {
    if (this.isJumping) return;
    this.isJumping = true;

    this.tweens.add({
        targets: this.player,
        displayOriginY: this.player.displayOriginY + 24,
        duration: 240,
        yoyo: true,
        ease: 'Sine.easeOut',
        onComplete: () => { this.isJumping = false; },
    });
}