.content
  details
    summary Open details
    p Lorem, ipsum dolor sit amet consectetur adipisicing elit. Totam cupiditate sit blanditiis itaque quasi sunt optio repellendus, quaerat nam porro dolores beatae earum illum obcaecati animi nobis quam voluptates minus.
  
  details
    summary Open details
    p Lorem ipsum dolor sit amet, consectetur adipisicing elit. Doloribus perferendis fugiat tenetur officiis natus dolorem numquam placeat incidunt nesciunt maxime vitae possimus, ab, unde quos eveniet reprehenderit fugit corporis et?
  
  details#details(open)
    summary Open details
    p Lorem ipsum dolor sit amet, consectetur adipisicing elit. Sapiente porro quasi nesciunt tenetur maxime voluptates ea velit, architecto totam earum id ab alias rem quia repellendus soluta vel dolore fuga.

  p.text-right
    button(onclick="closeDetails()") Close details
View Compiled
body
  margin: 0
  height: 100vh
  overflow: hidden
  font-family: sans-serif
  background: linear-gradient(45deg, rgb(251, 171, 126), rgb(247, 206, 104))
  
.content    
  position: absolute
  top: 50%
  left: 50%
  transform: translate(-50%, -50%)
  padding: 1em
  width: 50vw

details
  min-width: 100%
  
  // styling
  margin: 0.25em auto  
  p
    margin: 0
    padding: 0.25em 1em
  
  summary
    color: #3b393d
    cursor: pointer
    user-select: none
    
    // styling    
    border-radius: 0.35em
    padding: 1em
    border-bottom: 1px solid red
    background: linear-gradient(45deg, rgb(246, 146, 89), rgb(241, 105, 117))
    color: white
    
    // &::-webkit-details-marker
    //   background: url(right-arrow.svg)
    //   color: transparent
  
    &:forus
    outline: none

.text-right
  text-align: right
  
button
  position: relative
  padding-left: 1em
  border: none
  background-color: transparent
  background-clip: padding-box
  color: #eee
  
  &::before
    position: absolute
    left: 0
    top: 0
    content: "▲"
    transform: rotate(-90deg)
    font-size: inherit
  
  &:focus
  outline: none
  
[open] ~ p button
  color: #3b393d
  cursor: pointer
  
  &::before
    transform: rotate(0deg)
View Compiled
function closeDetails() {
  $("details[open]")
    .removeAttr("open");
}

$("details").on("click", function() {
    $("details[open]")
        .not(this)
        .removeAttr("open");
});

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js