:root{
  --bg:#f7f5f2;
  --panel:#ffffff;
  --accent:#e76f51;
  --muted:#6b6b6b;
  --tile-size:45px;
}
*{box-sizing:border-box;font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial;}
html,body,#app{height:100%;margin:0;background:var(--bg);color:#111;}
#app{display:flex;gap:12px;padding:12px;align-items:flex-start;justify-content:center}
#game-area{width:360px;display:flex;flex-direction:column;gap:10px;align-items:center}
#hud{width:100%;display:flex;gap:8px;align-items:center;justify-content:space-between}
#hud button{background:var(--accent);color:#fff;border:none;padding:8px 10px;border-radius:8px;cursor:pointer}
#hud button:disabled{opacity:.5;cursor:default}
#board-container{background:var(--panel);padding:8px;border-radius:12px;box-shadow:0 6px 18px rgba(0,0,0,.06)}
canvas{display:block;touch-action:none;border-radius:8px;background:linear-gradient(180deg,#fff,#fbfbfb)}
#bottom-row{width:100%;display:flex;justify-content:space-between;color:var(--muted);font-size:14px}
#sidebar{width:260px;background:var(--panel);padding:12px;border-radius:12px;box-shadow:0 6px 18px rgba(0,0,0,.06)}
#sidebar h3{margin:0 0 8px 0;font-size:16px}
#leaderboard{display:flex;flex-direction:column;gap:8px;max-height:420px;overflow:auto}
.lb-item{display:flex;align-items:center;gap:8px;padding:8px;border-radius:8px;background:#fff}
.lb-rank{font-weight:700;color:var(--accent);width:28px;text-align:center}
.lb-name{flex:1;font-size:14px}
.lb-score{font-weight:700}
@media (max-width:700px){
  #app{flex-direction:column;align-items:center;padding:8px}
  #sidebar{width:100%}
  #game-area{width:100%;max-width:420px}
}