#flex-button-container {
    display: flex;        
    flex-direction: column;  
    justify-content: center; 
    align-items: center;
}

.flex-button-box {
    margin: 15px;
    text-align: center;    
}

.button1 {
  border: none;
  color: white;
  padding: 16px 32px;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  font-size: 30px;
  margin: 4px 2px;
  transition-duration: 0.4s;
  cursor: pointer;
  background-color: #f9f9ff; 
  color: #111; 
  border: 4px solid #4CAF50;
}

.button1:hover {
  background-color: #4CAF50;
  color: white;
}