@angular/cdk/a11y-prebuilt.css

Angular Material Component Development Kit

.cdk-visually-hidden {
  border: 0;
  clip: rect(0 0 0 0);
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  width: 1px;
  white-space: nowrap;
  outline: 0;
  -webkit-appearance: none;
  -moz-appearance: none;
  left: 0;
}
[dir=rtl] .cdk-visually-hidden {
  left: auto;
  right: 0;
}