Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

@mixin mq-hoge {
  @media (max-width: 100px) {
    @content;
  }
}

.hoge {
  background-color:tomato;
  @include mq-hoge {
    background-color:red;
  }
}

.hoge__elm {
  background-color:limegreen;
  @include mq-hoge {
    background-color:tomato;
  }
}

SassMeister-output.css

.hoge {
  background-color: tomato;
}

@media (max-width: 100px) {
  .hoge {
    background-color: red;
  }
}

.hoge__elm {
  background-color: limegreen;
}

@media (max-width: 100px) {
  .hoge__elm {
    background-color: tomato;
  }
}