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<div class="loading">Loading</div>

.loading:after {
    overflow: hidden;
    display: inline-block;
    vertical-align: bottom;
    -webkit-animation: ellipsis 2s infinite;
    -moz-animation: ellipsis 2s infinite;
    animation: ellipsis 2s infinite;
    content: "\2026"; /* ascii code for the ellipsis character */
}
@-moz-keyframes ellipsis {
    from {
        width: 2px;
    }
    to {
        width: 15px;
    }
}
@-moz-keyframes ellipsis {
  from {
    width: 2px;
  }
  to {
    width: 15px;
  }
}

@-webkit-keyframes ellipsis {
  from {
    width: 2px;
  }
  to {
    width: 15px;
  }
}