body {  
  font-family: sans-serif;  
}  

.container {  
  width: 500px;  
  margin: 0 auto;  
  padding: 20px;  
  border: 1px solid #ccc;  
  border-radius: 5px;  
}  

#coupons p {  
  margin-bottom: 5px;  
}  

#error {  
  color: red;  
  margin-top: 10px;  
}