Sass

@mixin clearfix($before, $after){
    &:after{
        content: '';
        clear: both;
        display: block;
    }
}

$link-color: #8bb62b;
$link-hover-color: #96d30d;
$container-font-size: 16px;

.container{
    @include clearfix();
    font-size: $container-font-size;

    a{
        color: $link-color;
        &:hover{
            color: $link-hover-color;
        }
    }
}