summary::-webkit-details-marker{display:none;}
summary::-moz-list-bullet{list-style-type:none;}
summary::marker{display:none;} 
summary {
   display:inline-block;
   padding: .3em .5em .3em .4em;
   cursor: pointer;
}

summary:after {  
  content: "▼";
  margin-right: .3em;
}
details[open] > summary:after {
  content: "▲";
}
summary ~ * {
   padding:0 1em 0 1em;
}
summary:focus {
  outline:0;
  box-shadow: inset 0 0 1px rgba(0,0,0,0.3), inset 0 0 2px rgba(0,0,0,0.3);
}
details{
  display:block;
  margin-bottom: .5rem;
}