Mixins in SCSS

    font-size: $big-font-size;
    letter-spacing: 0.5px;
    font-family: 'Arvo Italic', monospace;
        @include media-query($on-palm) {
         font-size: $big-font-size * 0.8; // Reduce by 20%
        }

 @mixin border-radius($radius) {
  -webkit-border-radius: $radius;
     -moz-border-radius: $radius;
      -ms-border-radius: $radius;
       -o-border-radius: $radius;
          border-radius: $radius;
}

button{
    background-color: $theme-color;
    border: 0px solid;
    padding: 0.7rem 3rem;
    @include border-radius(2rem);

}