For having a trasition effect like a highlighter just to highlight the text and fade off the bg color, we used the following:
.field-error {_x000D_
color: #f44336;_x000D_
padding: 2px 5px;_x000D_
position: absolute;_x000D_
font-size: small;_x000D_
background-color: white;_x000D_
}_x000D_
_x000D_
.highlighter {_x000D_
animation: fadeoutBg 3s; /***Transition delay 3s fadeout is class***/_x000D_
-moz-animation: fadeoutBg 3s; /* Firefox */_x000D_
-webkit-animation: fadeoutBg 3s; /* Safari and Chrome */_x000D_
-o-animation: fadeoutBg 3s; /* Opera */_x000D_
}_x000D_
_x000D_
@keyframes fadeoutBg {_x000D_
from { background-color: lightgreen; } /** from color **/_x000D_
to { background-color: white; } /** to color **/_x000D_
}_x000D_
_x000D_
@-moz-keyframes fadeoutBg { /* Firefox */_x000D_
from { background-color: lightgreen; }_x000D_
to { background-color: white; }_x000D_
}_x000D_
_x000D_
@-webkit-keyframes fadeoutBg { /* Safari and Chrome */_x000D_
from { background-color: lightgreen; }_x000D_
to { background-color: white; }_x000D_
}_x000D_
_x000D_
@-o-keyframes fadeoutBg { /* Opera */_x000D_
from { background-color: lightgreen; }_x000D_
to { background-color: white; }_x000D_
}
_x000D_
<div class="field-error highlighter">File name already exists.</div>
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