html,body{height:100%;margin:0;display:flex;justify-content:center;align-items:center;background-color:#1e1e1e;overflow:hidden}.game-container{display:flex;align-items:center;display:none}canvas#game{background-color:#0d1a2b;border:5px solid #fff;margin:0 20px;display:block}.scoreboard{position:fixed;top:0;left:0;width:100%;background-color:#09121b;color:#fff;font-family:sans-serif;font-size:18px;display:flex;justify-content:space-around;padding:10px 0;z-index:1000}.popup,.game-over-popup{position:fixed;top:0;left:0;width:100%;height:100%;display:flex;justify-content:center;align-items:center;background-color:rgba(0,0,0,.7);z-index:10;color:#fff;font-family:sans-serif;text-align:center}.popup .content,.game-over-popup .content{background-color:#0d1a2b;padding:20px;border-radius:10px;box-shadow:0 0 10px rgba(0,0,0,.5)}.popup .content button,.game-over-popup .content button{margin-top:20px;padding:10px 20px;font-size:18px;background-color:#fff;border:none;cursor:pointer;border-radius:5px}.game-over-popup{display:none}.speed-up-alert{position:absolute;top:50px;width:100%;text-align:center;color:yellow;font-size:24px;font-weight:bold;display:none;font-family:sans-serif}#speed-up-button{position:fixed;bottom:50%;right:20px;width:50px;height:50px;cursor:pointer;display:none}@media (max-width:768px){.game-container{flex-direction:column}canvas#game{width:90vw;height:auto}}