body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f5f7fa;
  color: #222;
}

.container {
  max-width: 400px;
  margin: 80px auto;
  text-align: center;
}

h1 {
  margin-bottom: 0;
}

.subtitle {
  margin-top: 4px;
  color: #666;
}

.card {
  background: white;
  padding: 24px;
  margin-top: 24px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

input {
  width: 100%;
  padding: 12px;
  margin: 8px 0;
  border-radius: 6px;
  border: 1px solid #ccc;
}

button {
  width: 100%;
  padding: 12px;
  margin-top: 12px;
  border: none;
  border-radius: 6px;
  background: #1a73e8;
  color: white;
  font-size: 16px;
  cursor: pointer;
}

button.secondary {
  background: #555;
}

button:hover {
  opacity: 0.9;
}

#message {
  margin-top: 12px;
  color: #d00;
}

.topbar {
  display: flex;
  justify-content: space-between;
  padding: 16px;
  background: white;
  border-bottom: 1px solid #ddd;
}

.iframe-container {
  width: 100%;
  height: calc(100vh - 70px);
}

iframe {
  width: 100%;
  height: 100%;
  border: none;
}