No space between files in issue tracker

Please see the attached screenshot. There is no space between files, from the second file onwards. This is due to the following code:

issue-attachment-list.less

.issue-attachment-list li {
  position: relative;
  float: left;
  margin: 0 15px 13px 0;
}

reset.less

body.adg3 dd+dd, body.adg3 li+li {
  margin: 0;
}

Simply adding !important to CSS code in issue-attachment-list.less fixes the problem.