#clockNumbers {
  font-family: Roboto, sans-serif;
  font-size: 80px;
  line-height: 80%;
}

#clockPeriod {
  color: #FFF;
  font-size: 45px;
  line-height: 80%;
}

#clockSeconds {
  font-family: Roboto, sans-serif;
  font-weight: 100;
  font-size: 35px;
  line-height: 80%;
}

#clockDate {
  font-size: 35px;
  margin-left: 5px;
  font-family: "Roboto Condensed", sans-serif;
  font-weight: 400;
}

.col-centered{
    float: none;
    margin: 0 auto;
}

  #clockNumbers {
  font-family: Roboto, sans-serif;
  font-size: 80px;
  line-height: 80%;
}

#clockPeriod {
  color: #FFF;
  font-size: 42px;
  line-height: 80%;
}

#clockSeconds {
  font-family: Roboto, sans-serif;
  font-weight: 100;
  font-size: 35px;
  line-height: 80%;
}

#clockDate {
  font-size: 35px;
  margin-left: 5px;
  font-family: "Roboto Condensed", sans-serif;
  font-weight: 400;
}

.col-centered{
    float: none;
    margin: 0 auto;
}

Reduce size of period font
Reduce size of period font
