form {
  margin-bottom: 2rem;
  background: #f9f9f9;
  padding: 1.5rem;
  border-radius: 10px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.1);
}
label {
  display: block;
  margin-top: 1rem;
  font-weight: bold;
}
select, input[type="number"] {
  width: 100%;
  padding: 0.5rem;
  margin-top: 0.3rem;
  border: 1px solid #ccc;
  border-radius: 6px;
}
button {
  margin-top: 1.5rem;
  padding: 0.6rem 1.2rem;
  background: #d92332;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}
button:hover {
  background: #b71c29;
}
.arena-wrapper {
  margin-top: 2rem;
  text-align: center;
}
.arena-plan {
  max-width: 600px;
  width: 100%;
  border: 1px solid #ccc;
  border-radius: 8px;
}
.legend {
  margin-top: 0.5rem;
  font-style: italic;
  color: #555;
}