align div right

.row {
  width: 100%;
  display: flex;
  flex-direction: row;
  justify-content: center;
}
.block {
  width: 100px;
}

#cTask {
  background-color: lightgreen;
}

#button {
  position: relative;
  float: right;
}

#addEventForm {
  position: relative;
  float: right;
  border: 2px solid #003B62;
  font-family: verdana;
  background-color: #B5CFE0;
  padding-left: 10px;
}

<div class="row">
  <div class="block">Lorem</div>
  <div class="block">Ipsum</div>
  <div class="block">Dolor</div>
</div>