Generated by SassMeister.com.

SassMeister-input-HTML.html

<div>日本語</div>

SassMeister-input.scss

// ----
// Sass (v3.4.7)
// Compass (v1.0.1)
// Bourbon (v4.0.2)
// Neat (v1.6.0)
// ----

@import "bourbon/bourbon";
@import "neat/neat";

body {
  line-height: 1;
}

div {
  @include hide-text();
  @include size(2em);
  background: tomato;
}

SassMeister-output.css

* {
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}

body {
  line-height: 1;
}

div {
  overflow: hidden;
  height: 2em;
  width: 2em;
  background: tomato;
}
div:before {
  content: "";
  display: block;
  width: 0;
  height: 100%;
}

SassMeister-rendered.html

<div>日本語</div>