:root{
  --bg: #87ceeb;
  --ground: #2d8a2d;
  --hud-bg: rgba(0,0,0,0.35);
  --hud-color: #fff;
}
*{box-sizing:border-box;margin:0;padding:0;font-family:Inter,Arial,Helvetica,sans-serif}
html,body{height:100%}
body{background:var(--bg);display:flex;align-items:stretch;justify-content:center;overflow:hidden}
#game{display:block;width:100vw;height:100vh;background:linear-gradient(#87ceeb,#cdefff 60%);touch-action:none}
#ui{position:absolute;left:0;top:0;right:0;pointer-events:none}
.top-left{position:fixed;left:12px;top:12px;pointer-events:auto;color:var(--hud-color)}
.top-left > div{background:var(--hud-bg);padding:6px 10px;border-radius:8px;margin-bottom:6px;font-weight:600}
.top-right{position:fixed;right:12px;top:12px;display:flex;gap:8px;align-items:center;pointer-events:auto}
#difficulty,#start,#pause,#restart{padding:8px 10px;border-radius:8px;border:none;font-weight:600;background:rgba(255,255,255,0.95)}
#difficulty{background:white}
#start{background:linear-gradient(180deg,#4caf50,#3b9a44);color:white}
#pause{background:linear-gradient(180deg,#ffb74d,#ff9a2d)}
#restart{background:linear-gradient(180deg,#ef5350,#d53939);color:white}
@media (max-width:600px){
  #difficulty,#start,#pause,#restart{padding:6px 8px;font-size:14px}
  .top-left > div{font-size:14px;padding:6px 8px}
}