body {
  font-family: sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  background: #f3f4f6;
  padding: 1em;
  box-sizing: border-box;
}

main {
  background: white;
  padding: 2em;
  border-radius: 1em;
  box-shadow: 0 0 1em rgba(0,0,0,0.1);
  max-width: 400px;
  width: 100%;
  text-align: center;
  box-sizing: border-box;
}

input, button {
  display: block;
  width: 100%;
  margin: 1em 0;
  padding: 1em;
  font-size: 1.2em;
  border-radius: 0.5em;
  border: 1px solid #ccc;
  box-sizing: border-box;
}

input {
  background: #fafafa;
  transition: border-color 0.3s, background-color 0.3s;
}

input:focus {
  outline: none;
  border-color: #3b82f6;
  background: white;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

button {
  background: #3b82f6;
  color: white;
  border: none;
  cursor: pointer;
  transition: background-color 0.3s, transform 0.2s;
}

button:hover {
  background: #2563eb;
  transform: translateY(-1px);
}

button:active {
  transform: translateY(0);
}

#mic, #speaker, #alert {
  font-size: 1.5em;
  margin-top: 1em;
  color: #10b981;
}

#alert {
  color: #ef4444;
  font-weight: bold;
}

/* Responsive design */
@media (max-width: 480px) {
  body {
    padding: 0.5em;
  }
  
  main {
    padding: 1.5em;
    max-width: 100%;
  }
  
  input, button {
    font-size: 1.1em;
    padding: 0.8em;
  }
}