.head {
  text-align: center;
  margin-bottom: 20px;
}

.head h1 {
  color: #d90429;
  font-size: 2.2rem;
  margin-bottom: 10px;
}

.head p {
  font-size: 1rem;
  color: #333;
}

.signal-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

.signal-card {
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  padding: 15px;
  text-align: center;
  transition: transform 0.3s ease;
}

.signal-card:hover {
  transform: translateY(-5px);
}

.signal-card img {
  width: 100%;
  max-height: 180px;
  object-fit: contain;
  margin-bottom: 15px;
}

.signal-card h2 {
  font-size: 1.2rem;
  color: #d90429;
  margin-bottom: 10px;
}

.signal-card p {
  font-size: 0.95rem;
  color: #444;
}

.footer {
  text-align: center;
  margin-top: 40px;
  font-size: 0.9rem;
  color: #666;
}