<!DOCTYPE html>
<html>
<head><style>
  div.a {
    -moz-column-count: 2;
    overflow-y: hidden;
    background: yellow;
  }
  div.b {
    background: orange;
    clear: both;
    margin-top: 946982.46874999995cm;
  }
  div.c {
    position: fixed;
    background: red;
  }
</style></head>
<body
  ><div class="a"><div
    ><div class="b"><li></li></div
    ><div class="c"></div
  ></div></div
></body>
</html>