difference files between scss and sass

sass.sass

//Scss syntax
@mixin button-base() {
    @include typography(button);
    @include ripple-surface;
    @include ripple-radius-bounded;
    display: inline-flex;
    position: relative;
    height: $button-height;
    border: none;
    vertical-align: middle;
    &:hover {
        cursor: pointer;
    }
    &:disabled {
        color: $mdc-button-disabled-ink-color;
        cursor: default;
        pointer-events: none;
    }
}

//Sass Syntax
@mixin button-base()
  @include typography(button)
  @include ripple-surface
  @include ripple-radius-bounded

  display: inline-flex
  position: relative
  height: $button-height
  border: none
  vertical-align: middle

  &:hover
    cursor: pointer

  &:disabled
    color: $mdc-button-disabled-ink-color
    cursor: default
    pointer-events: none