What is the mouse down selector in CSS?

 https://stackoverflow.com/questions/16715274/what-is-the-mouse-down-selector-in-css

I figured out that this behaves like a mousedown event:

&,

    &:hover,

    &:focus,

    &:active,

    &.active,

    &:active:focus,

    &:active:hover,

    &.active:focus,

    &.active:hover,

    .open > &.dropdown-toggle,

    .open > &.dropdown-toggle:focus,

    .open > &.dropdown-toggle:hover {

      background-color: $btn-color;

      color: $white-color;

    }

    &:focus,

    &:active,

    &:hover{

      @include button-shadow-color($btn-color);

    }

button:active:hover {}