#contents .cbbox:hover {
    opacity: 1;
}

.cbbutton{
  margin: 20px auto;
  text-align: center; 
}

.cbbutton a{
  text-decoration:none;
  padding: 0.5rem 1rem;
  color:#000;
  font-size: 1.2rem;
  background: #6cbb5a;
  border: solid #000 1px; 
  border-radius: 30px;
  opacity: 0.8;
 }

.cbbutton a:hover {
  color: #fff; 
  cursor: pointer;
  opacity: 1;
}
@media screen and (max-width:400px) { 
  .cbbutton{
   width:100%;
   font-size:2rem;}
}