@media (prefers-reduced-motion: reduce) {
  .fade {
    transition: none;
  }
}

.fade:not(.show) {
  opacity: 0;
}

.collapse:not(.show) {
  display: none;
}

.collapsing {
  position: relative;
  height: 0;
  overflow: hidden;
  transition: height 0.35s ease;
}

@media (prefers-reduced-motion: reduce) {
  .collapsing {
    transition: none;
  }
}

.dropup,
.dropright,
.dropdown,
.dropleft {
  position: relative;
}

.dropdown-toggle {
  white-space: nowrap;
}

.dropdown-toggle::after {
  display: inline-block;
  margin-left: 0.255em;
  vertical-align: 0.255em;
  content: "";
  border-top: 0.3em solid;
  border-right: 0.3em solid transparent;
  border-bottom: 0;
  border-left: 0.3em solid transparent;
}

.dropdown-toggle:empty::after {
  margin-left: 0;
}

.dropdown-menu {
  /*font-family: Arial, Helvetica, sans-serif;*/   /*d add*/
  position: absolute;
  top: 100%;
  left: 0;
  z-index: 1000;
  display: none;
  float: left;
  min-width: 10rem;
  padding: 0.5rem 0;
  /*margin: 0.125rem 0 0;*/
  margin: 0.125rem 0 0;
  font-size: 1rem;
  color: #212529;
  text-align: left;
  list-style: none;
  background-color: #fff;
  background-clip: padding-box;
  border: 1px solid rgba(0, 0, 0, 0.15);
  border-radius: 0.25rem;
  box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.175);
}