:root{
  --bg:#0f1724;
  --card:#0b1220;
  --accent:#7c3aed;
  --panel:#0b1522;
  --text:#e6eef8;
  --muted:#9fb0c8;
  --size:64px;
  --gap:8px;
}

/* layout */
*{box-sizing:border-box;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,"Helvetica Neue",Arial;}
body{margin:0;background:linear-gradient(180deg,#071022,var(--bg));color:var(--text);min-height:100vh;display:flex;align-items:center;justify-content:center;padding:28px;}
.app{width:100%;max-width:980px}
header{display:flex;align-items:flex-start;gap:16px;flex-direction:column;margin-bottom:14px}
h1{margin:0;font-size:1.8rem}
.subtitle{margin:0;color:var(--muted)}

.controls{background:var(--panel);padding:12px;border-radius:10px;display:flex;flex-direction:column;gap:10px;margin-bottom:16px}
.controls .row{display:flex;gap:12px;align-items:center;flex-wrap:wrap}
.controls label{font-size:0.9rem;color:var(--muted)}
.controls select,input,button{padding:8px 10px;border-radius:8px;border:1px solid rgba(255,255,255,0.06);background:transparent;color:var(--text);outline:none}
.controls button{cursor:pointer}
button:disabled{opacity:0.5;cursor:default}

.board-wrap{display:flex;justify-content:center;align-items:center;margin-bottom:12px}
.board{display:grid;gap:var(--gap);background:rgba(255,255,255,0.02);padding:12px;border-radius:12px;box-shadow:0 6px 18px rgba(2,6,23,0.6)}

.tile{
  width:var(--size);height:var(--size);display:flex;align-items:center;justify-content:center;border-radius:8px;
  font-weight:700;color:rgba(0,0,0,0.7);user-select:none;
  transition:transform .18s ease, box-shadow .18s;
  box-shadow: 0 4px 10px rgba(2,6,23,0.5);
  border:2px solid rgba(0,0,0,0.12);
}

/* accessible labels small */
.tile .label{font-size:0.78rem;color:rgba(0,0,0,0.55)}

.status{margin-left:auto;color:var(--muted);display:flex;gap:12px;align-items:center}
.rotate-controls{display:flex;align-items:center;gap:8px}
.rotate-buttons{display:flex;gap:6px}
.notes{color:var(--muted);font-size:0.9rem;margin-top:6px}

footer{color:var(--muted);font-size:0.8rem;margin-top:12px;text-align:center}

/* modal */
.modal{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(2,6,23,0.6)}
.hidden{display:none}
.modal-content{background:var(--card);padding:20px;border-radius:12px;min-width:260px;text-align:center}
.modal-actions{display:flex;gap:8px;justify-content:center;margin-top:12px}

/* responsive sizes */
@media (max-width:640px){
  :root{--size:52px}
  .controls .row{flex-direction:column;align-items:stretch}
  .status{margin-left:0;justify-content:space-between}
}