class with fade animation code example

Example 1: animation fade in css

#test p {
    margin-top: 25px;
    font-size: 21px;
    text-align: center;

    -webkit-animation: fadein 2s; /* Safari, Chrome and Opera > 12.1 */
       -moz-animation: fadein 2s; /* Firefox < 16 */
        -ms-animation: fadein 2s; /* Internet Explorer */
         -o-animation: fadein 2s; /* Opera < 12.1 */
            animation: fadein 2s;
}

@keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Firefox < 16 */
@-moz-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Safari, Chrome and Opera > 12.1 */
@-webkit-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Internet Explorer */
@-ms-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

/* Opera < 12.1 */
@-o-keyframes fadein {
    from { opacity: 0; }
    to   { opacity: 1; }
}

Example 2: css fade div

ol {
  border   : 1px #d8d8d8 dashed;
  position : relative;
}

ol:after {
  content  : "";
  position : absolute;
  z-index  : 1;
  bottom   : 0;
  left     : 0;
  pointer-events   : none;
  background-image : linear-gradient(to bottom, 
                    rgba(255,255,255, 0), 
                    rgba(255,255,255, 1) 90%);
  width    : 100%;
  height   : 4em;
}