<div class="box">
  <p class="one-line-ellipsis">Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish,Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish, Hello Fatfish</p>
</div>

* {
  margin: 0;
  padding: 0; 
}

body {
  padding: 15px;
  color: #324b64;
}

.box {
  padding: 10px;
  background-color: #f5f6f9;
  border-radius: 6px;
  font-size: 12px;
}

.one-line-ellipsis {
  /* Key Style */
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  max-width: 375px;
}