body {
  font-family: Arial, sans-serif;
  background: #f7f7f7;
  padding: 30px;
  text-align: center;
}

.sim-container {
  max-width: 500px;
  margin: auto;
  background: #fff;
  padding: 20px;
  border-radius: 16px;
  box-shadow: 0 0 15px rgba(0,0,0,0.1);
}

input[type=range] {
  width: 100%;
}

#bulb {
  width: 100px;
  margin-top: 20px;
  transition: filter 0.3s;
}