//Определение и изменение размеров контейнера:
@mixin container {
  width: 100%;
  max-width: $container-lg;
  margin: 0 auto;
  padding-left: $p;
  padding-right: $p;
  @media screen and (max-width: $breakpoint-lg) {
    max-width: $container-md;
  }

  @media screen and (max-width: $breakpoint-md) {
    max-width: $container-sm;
  }

  @media screen and (max-width: $breakpoint-sm) {
    max-width: none;
  }
}

@function strip-unit($number) {
  @if type-of($number) == "number" and not unitless($number) {
    @return $number / ($number * 0 + 1);
  }
  @return $number;
}

@function calcFluidFontSize($f-min, $f-max, $w-min, $w-max, $units: px) {
  $f-min: strip-unit($f-min);
  $f-max: strip-unit($f-max);
  $w-min: strip-unit($w-min);
  $w-max: strip-unit($w-max);
  $k: ($f-max - $f-min)/ ($w-max - $w-min);
  $b: $f-min - $k * $w-min;
  $b: $b + $units;
  @return calc(#{$k} * 100vw + #{$b});
}

@mixin fluid($property, $f-min, $f-max, $w-min: $breakpoint-to-fluid, $w-max: $base-vw, $fallback: false) {
  #{$property}: $f-min;
  @media (min-width: $w-min) {
    @if ($fallback) {
      #{$property}: $fallback;
    }
    #{$property}: calcFluidFontSize($f-min, $f-max, $w-min, $w-max, px);
  }
  @media (min-width: $w-max) {
    #{$property}: $f-max;
  }
}