@mixin focus-with-keyboard {
  html[data-whatinput="keyboard"] &:focus {
    @content;
  }
}

@mixin focus-without-keyboard {
  html[data-whatinput="initial"] &:focus,
  html[data-whatinput="mouse"] &:focus,
  html[data-whatinput="touch"] &:focus {
    @content;
  }
}

@mixin focus-clear {
  outline: none;
}

@mixin focus-clear-without-keyboard {
  @include focus-without-keyboard {
    @include focus-clear;
  }
}

a {
  @include focus-clear-without-keyboard;
}

.btn {
  @include focus-clear;

  @include focus-with-keyboard {
    background-color: lightgray;
  }
}