* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  background:#f5f5f5;
  font-family: Arial, sans-serif;
  display:flex;
  justify-content:center;
  align-items:center;
  height:100vh;
}

.container {
  text-align:center;
  width:90%;
  max-width:600px;
  padding:20px;
  background:#fff;
  border-radius:8px;
  box-shadow:0 4px 12px rgba(0,0,0,.1);
}

#result {
  margin-top:0px;
  font-size:1.5rem;
  text-align:center;
  width:100%;
  padding:20px;
  background:#fff;
  border-radius:8px;
  box-shadow:0 4px 12px rgba(0,0,0,.1);
}

#spinBtn {
  margin-top:15px;
  padding:.5rem 1.2rem;
  font-size:1rem;
  cursor:pointer;
  background:#28a745;
  color:white;
  border:none;
  border-radius:4px;
  transition:.2s;
}
#spinBtn:hover {background:#218838;}

.hidden{display:none;}