.file--x-office-document {
  background: none;
}

a[href$=".pdf"]:before {
  content: url("/sites/default/files/icons/pdf-icon.png");
  padding-right:3px;
}
a[href$=".PDF"]:before {
  content: url("/sites/default/files/icons/pdf-icon.png");
  padding-right:3px;
}

a[href$=".xls"]:before
{
  content: url("/sites/default/files/icons/excel-icon.png");
  padding-right:2px;
}
a[href$=".xlsx"]:before
{
  content: url("/sites/default/files/icons/excel-icon.png");
  padding-right:2px;
}

a[href$=".doc"]:before
{
  content: url("/sites/default/files/icons/word-icon.png");
  padding-right:2px;
}
a[href$=".docx"]:before
{
  content: url("/sites/default/files/icons/word-icon.png");
  padding-right:2px;
}
a[href$=".ppt"]:before
{
  content: url("/sites/default/files/icons/powerpoint-icon.png");
  padding-right:2px;
}
a[href$=".pptx"]:before
{
  content: url("/sites/default/files/icons/powerpoint-icon.png");
  padding-right:2px;
}