body {
  margin: 0;
  font-family: "Courier New", monospace;
  background: url("bg.jpg") no-repeat center/cover fixed;
  color: #f0f0f0;
}

.container {
  max-width: 750px;
  margin: 6vh auto;
  padding: 2rem;
  background: rgba(0, 0, 0, 0.65);
  border-radius: 18px;
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

h1 {
  margin-top: 0;
  text-align: center;
}

.instrucciones {
  background: rgba(255, 255, 255, 0.08);
  padding: 1rem;
  border-radius: 10px;
  font-size: 0.95rem;
  margin-bottom: 2rem;
}

.pista {
  margin: 1.2rem 0;
}

input {
  padding: 0.45rem;
  border: none;
  border-radius: 8px;
  width: 70%;
  max-width: 320px;
}

button {
  margin-left: 0.5rem;
  padding: 0.45rem 1rem;
  border: none;
  border-radius: 8px;
  background: #444;
  color: #fff;
  cursor: pointer;
}

button:hover {
  background: #666;
}

.hidden {
  display: none;
}

#mensaje-binario {
  margin-top: 2rem;
  font-size: 0.82rem;
  color: #00ffc8;
  word-break: break-word;
  white-space: pre-wrap;
  background: rgba(0, 0, 0, 0.45);
  padding: 1rem;
  border-radius: 10px;
}