.u-button {
  width: 100%;
  white-space: nowrap;
}
.u-button__text {
  white-space: nowrap;
  line-height: 1;
}
.u-button:before {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100%;
  height: 100%;
  border: inherit;
  border-radius: inherit;
  transform: translate(-50%, -50%);
  opacity: 0;
  content: " ";
  background-color: #000;
  border-color: #000;
}
.u-button--active:before {
  opacity: 0.15;
}
.u-button__icon + .u-button__text:not(:empty), .u-button__loading-text {
  margin-left: 4px;
}
.u-button--plain.u-button--primary {
  color: var(--u-primary);
}
.u-button--plain.u-button--info {
  color: var(--u-info);
}
.u-button--plain.u-button--success {
  color: var(--u-success);
}
.u-button--plain.u-button--error {
  color: var(--u-error);
}
.u-button--plain.u-button--warning {
  color: var(--u-warning);
}