body { 
  font-family: sans-serif; 
  text-align: center; 
  margin-top: 60px; 
}

input, textarea { 
  font-size: 16px; 
  margin: 5px; 
  padding: 5px; 
  width: 300px;
}

button { 
  font-size: 20px; 
  padding: 12px 30px; 
  cursor: pointer; 
  margin-top: 10px;
}

.on { background: #2ecc71; color: white; }
.off { background: #e74c3c; color: white; }
.error { background: #f39c12; color: black; }

textarea { height: 100px; }