:root{color-scheme:dark;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif}*{box-sizing:border-box;touch-action:manipulation;-webkit-tap-highlight-color:transparent}html,body{margin:0;width:100%;height:100%;overflow:hidden;background:#0f172a}body{display:block}#game-canvas{width:100vw;height:100dvh;display:block}.overlay-screen{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;background:#020617c7;z-index:20}.overlay-hidden{display:none}.menu-panel,.howto-panel{width:min(90vw,520px);border:1px solid rgba(148,163,184,.35);border-radius:18px;background:#0f172af2;box-shadow:0 20px 50px #00000059;padding:24px 18px;color:#e2e8f0}.howto-panel{width:min(94vw,960px);max-height:min(92dvh,980px);padding:28px 24px}#game-logo{width:min(280px,70vw);display:block;margin:0 auto 18px}.menu-buttons{display:grid;gap:12px}button{appearance:none;border:0;border-radius:12px;padding:13px 16px;font-size:1rem;font-weight:700;color:#0f172a;background:#e2e8f0;cursor:pointer}button:active{transform:translateY(1px)}.game-over-actions{position:fixed;left:50%;bottom:max(18px,env(safe-area-inset-bottom));transform:translate(-50%);z-index:30;display:flex;gap:14px;padding:10px 12px;border-radius:999px;border:1px solid rgba(148,163,184,.35);background:#0f172aeb;box-shadow:0 10px 30px #00000059}.game-over-actions.overlay-hidden{display:none}.game-over-actions button{width:54px;height:54px;border-radius:999px;padding:0;display:grid;place-items:center;background:#e2e8f0;color:#0f172a}.game-over-actions svg{width:26px;height:26px}.howto-panel h2{margin:0 0 10px;text-align:center}.howto-panel p{margin:0 0 12px;text-align:center;line-height:1.45;font-size:1.08rem}#how-to-canvas{width:100%;height:min(60dvh,540px);display:block;border-radius:14px;border:1px solid rgba(148,163,184,.35);background:linear-gradient(180deg,#0f172a,#1e293b);margin:8px 0 16px}