Generated by SassMeister.com.

SassMeister-input-HTML.html

<div class="reference-center">OR</div>
<div class="relative">
  <div class="center-this-thing">OR</div>
</div>

SassMeister-input.scss

// ----
// Sass (v3.3.14)
// Compass (v1.0.0)
// ----

.reference-center {
  font-size: 2em;
  text-align: center;
}

.relative {
  position: relative;
}

.center-this-thing {
  font-size: 2em;
  left: 50%;
  position: absolute;
  transform: -webkit-translateX(-50%); // Needed for iOS
  transform: translateX(-50%);
}

SassMeister-output.css

.reference-center {
  font-size: 2em;
  text-align: center;
}

.relative {
  position: relative;
}

.center-this-thing {
  font-size: 2em;
  left: 50%;
  position: absolute;
  transform: -webkit-translateX(-50%);
  transform: translateX(-50%);
}

SassMeister-rendered.html

<div class="reference-center">OR</div>
<div class="relative">
  <div class="center-this-thing">OR</div>
</div>