AdminLTE/scss/dark/bootstrap/_accordion.scss

// Base styles

.accordion-button {
  color: $accordion-button-color-alt;
  background-color: $accordion-button-bg-alt;

  &:not(.collapsed) {
    color: $accordion-button-active-color-alt;
    background-color: $accordion-button-active-bg-alt;
    box-shadow: inset 0 ($accordion-border-width * -1) 0 $accordion-border-color-alt;

    &::after {
      background-image: escape-svg($accordion-button-active-icon-alt);
    }
  }

  // Accordion icon
  &::after {
    background-image: escape-svg($accordion-button-icon-alt);
  }

  &:hover {
    z-index: 2;
  }

  &:focus {
    border-color: $accordion-button-focus-border-color-alt;
    box-shadow: $accordion-button-focus-box-shadow-alt;
  }
}

.accordion-item {
  background-color: $accordion-bg-alt;
  border: $accordion-border-width solid $accordion-border-color-alt;
}

// Flush accordion items

.accordion-flush {
  .accordion-collapse {
    border-width: 0;
  }

  .accordion-item {
    border-right: 0;
    border-left: 0;

    &:first-child { border-top: 0; }
    &:last-child { border-bottom: 0; }
  }
}