<button class="button">button</button>

@btn-color: silver;
@light: black;

.button {
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 1.2rem;
  background-color: @btn-color;
  color: @light;
  text-transform: uppercase;
  border: none;
  transition: all 0.2s;
   &:hover {
    cursor: pointer;
    background-color: darken(@btn-color, 5%);
  }
}