I've created these to text boxes and want to add responsiveness to them, however, adding the @media doesn't work for some reason. I want the the right box move under the left box when the screen size is under x pixels.
/* CSS Document */
* {
  box-sizing: border-box;
}
#fullbodybg {
  margin-top: 20%;
}
/* Create two unequal columns that floats next to each other */
.column {
  float: left;
  padding: 10px;
  height: auto;
  /* Should be removed. Only for demonstration */
}
@media screen and (max-width: 1000px) {
  .column {
    width: 100%;
  }
}
.left {
  margin-left: 10%;
  width: 25%;
}
.right {
  margin-right: 10%;
  width: 55%;
}
/* Clear floats after the columns */
.row:after {
  content: "";
  display: table;
  clear: both;
}
.row {
  font-family: lato;
  font-style: normal;
  font-weight: 100;
  font-size: 15px;
  text-align: left;
}
<div class="row">
  <div class="column left">
    <h2>Angaben gemäß § 5 TMG</h2>
    <p>Max Muster<br>Musterweg<br>12345 Musterstadt<br><br>Vertreten durch:<br>Max Muster<br><br>Kontakt:<br>Telefon: 01234-789456<br>Fax: 1234-56789<br>E-Mail: max@muster.de<br><br>Umsatzsteuer-ID:<br>Umsatzsteuer-Identifikationsnummer gemäß
      §27a Umsatzsteuergesetz: Musterustid.<br><br>Wirtschafts-ID:<br>Musterwirtschaftsid<br><br>Aufsichtsbehörde:<br>Musteraufsicht Musterstadt</p>
  </div>
  <div class="column right">
    <h2>Haftungsausschluss:</h2>
    <p>Zweck einverstanden.</p>
  </div>
</div>