body {
  font-family: 'Inter', sans-serif;
  margin: 0;
  padding: 0;
  background: #f5f5f5;
}
header {
  background: #1f2937;
  color: white;
  padding: 1rem;
  text-align: center;
  font-size: 1.5rem;
  font-weight: bold;
}
.controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
}
.controls input, .controls select {
  padding: 0.5rem;
  font-size: 1rem;
  border-radius: 6px;
  border: 1px solid #ccc;
}
.controls button {
  padding: 0.5rem 1rem;
  font-size: 1rem;
  cursor: pointer;
  border: none;
  border-radius: 6px;
  background: #4f46e5;
  color: white;
  transition: 0.2s;
}
.controls button:hover {
  background: #6366f1;
}
#iframes {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 1rem;
}
iframe {
  width: 90%;
  max-width: 1000px;
  height: 600px;
  border: 2px solid #ddd;
  border-radius: 10px;
}