body {
  font-family: system-ui, sans-serif;
  padding: 20px;
  text-align: center;
  background: #f5f7fa;
}

#infoBox {
  background: white;
  padding: 20px;
  padding-bottom: 30px;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

#deviceInfo {
  margin: 25px auto;
}

#installBtn {
  display: none;
  padding: 12px 25px;
  margin: 25px auto;
  font-size: 18px;
  cursor: pointer;
}

#androidSteps {
  display: none;
  text-align: left;
  background: #f8f9fa;
  padding: 15px 20px;
  border-radius: 12px;
  margin: 10px 0;
  border: 1px dashed #999;
}

#iosSteps {
  display: none;
  text-align: left;
  background: #f8f9fa;
  padding: 15px 20px;
  border-radius: 12px;
  margin: 10px 0;
  border: 1px dashed #999;
}