* {
  margin: 0;
  padding: 0;
}

.center {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
}

.btn {
  display: inline-block;
  padding: 0.5rem 0.75rem;
  color: #0d6efd;
  background-color: transparent;
  border: 1px solid #0d6efd;
  border-radius: 5px;
  text-align: center;
  text-decoration: none;
  transition: 0.15s;
}

.btn:hover {
  color: #fff;
  background-color: #0d6efd;
}

.btn-group {
  display: inline-flex;
}

.btn-group > .btn-group:not(:last-child) > .btn,
.btn-group > .btn.dropdown-toggle-split:first-child,
.btn-group > .btn:not(:last-child):not(.dropdown-toggle) {
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

.btn-group > .btn-group:not(:first-child) > .btn,
.btn-group > .btn:nth-child(n + 3),
.btn-group > :not(.btn-check) + .btn {
  border-top-left-radius: 0;
  border-bottom-left-radius: 0;
}

.btn-group > .btn-group:not(:first-child),
.btn-group > :not(.btn-check:first-child) + .btn {
  margin-left: -1px;
}