x-collapse {
  display: block;
  position: relative;
  transition: 0.3s;
}
.is-dark-mode x-collapse {
  color: var(--color-text-light, #FEFEFE);
}
x-collapse .collapse-header {
  position: relative;
  padding: 0.5rem 0;
  line-height: 1em;
  cursor: pointer;
  user-select: none;
}
x-collapse .collapse-header:hover:after {
  animation: 0.75s fadeBreathe infinite;
}
x-collapse .collapse-header h4 {
  margin: 0;
}
x-collapse .collapse-header .collapse-action {
  position: absolute;
  top: calc(50% - 0.5rem);
  right: 0.75rem;
}
x-collapse .collapse-container {
  overflow: hidden;
  user-select: none;
  transition: 0.3s;
  max-height: 0;
  opacity: 0;
  transition: max-height 0.2s ease-out, opacity 0.2s;
}
x-collapse.collapse-expanded .collapse-container {
  opacity: 1;
}