.input-group > .input-group-addon:not(:last-child):not(:nth-last-child(2)) {
  border-right-width: 0;
}
.input-group > :not(.input-group-addon):not(.input-group-btn) + .input-group-addon {
  border-left-width: 0;
}
.input-group > .input-group-btn:not(:first-child) > .btn,
.input-group > .input-group-btn:not(:first-child) > .btn-group > .btn {
  margin-left: -1px;
  margin-right: -1px;
}
.input-group > .input-group-btn:not(:first-child):not(:last-child) > .btn,
.input-group > .input-group-btn:not(:first-child):not(:last-child) > .btn-group > .btn {
  border-radius: 0;
}