@mixin border-radius($size) {
    border-radius: $size;
}

$border-radius-sizes: 1, 2, 3, 10, 50, 60;

.br {
    @each $size in $border-radius-sizes {
        &-#{$size} {
            @include border-radius(#{$size}px);
        }
    }

    &-circle {
        @include border-radius(50%);
    }
}