.tt-grey {
  color: lightgrey;
}
.tt-left {
  float: left;
}
.tt-right {
  float: right;
}
.tt-center,
.tt-center.fa {
  display: -webkit-flex; /* Safari */
  -webkit-justify-content: center; /* Safari */
  display: flex;
  justify-content: center; /* Firefox, Chrome, IE 11, Opera */
}