@import "./variables";
@mixin ivue-elevation($value) {
      // 判断参数是否是 number
      @if type-of($value) !=number or not unitless($value) {
            @error "$value must be a unitless number";
      }

      @if $value < 0 or $value>24 {
            @error "$value must be between 0 and 24";
      }

      // map-get 查找键值
      box-shadow: #{map-get($ivue-elevation-umbra, $value)} $ivue-elevation-umbra-color,
                  #{map-get($ivue-elevation-penumbra, $value)} $ivue-elevation-penumbra-color,
                  #{map-get($ivue-elevation-ambient, $value)} $ivue-elevation-ambient-color;
}