<style>
.spoiler {
  border: 1px solid #e0e0e0;
  padding: 0 1em;
}
.spoiler details {
  padding: 1em 0;
}
.spoiler details + details { 
  border-top: 1px solid #e0e0e0;
}
.spoiler summary {
  color: #4d5895;
  cursor: pointer;
  font-size: 1.65em;
  font-weight: 700;
  outline-style: none;
  text-align:center;
}
.spoiler summary:hover {
  color: #F00;
}
.spoiler details div {
  overflow: hidden;
  padding: 1em 1em 0;
}
.spoiler details[open] div {
  animation: spoiler 0s;
}
@keyframes spoiler {
  0%   {max-height: 0;}
  100% {max-height: 10em;}
}
</style>