main.css

<style>
.collapsible {
	padding: 2px;
	width: 100%;
	border: none;
	outline: none;
	/* text-align: left; */
	font-size: 15px;
  }

  .active, .collapsible:hover {
	background-color: rgba(1, 141, 43, 0.712);
  }

  .collapsible:after {
	content: '\002B';
	font-weight: bold;
	float: right;
	margin-left: 5px;
  }
  
  .collapsible.active:after {
	content: "\2212";
  }
  
  /* .contentshow {
	padding: 0 18px;
	max-height: 0;
	overflow: hidden;
	transition: max-height 0.2s ease-out;
  } */
  
  .collapsible + .contentshow{
	display: none;
	transition: max-height 0.2s ease-out;
	padding: 0 18px;
  }
    
  .collapsible.active + .contentshow{
	display: block;
	transition: max-height 0.2s ease-out;
	padding: 0 18px;
  }
</style>