mes/WebContent/resource/ux/css/ClearButton.css

.ext-ux-clearbutton {
    width: 12px;
    height: 12px;
    background-image: url(../css/images/clear-text-icon.gif);
    background-position: 0 0;
    background-repeat: no-repeat;
    -moz-user-focus: ignore; /* https://developer.mozilla.org/en/CSS/-moz-user-focus */
    cursor: pointer;
    position: absolute;
    overflow:  hidden; /* IE 6 :-( */
    margin-top: 4px;
    background-color: white;
}

.ext-ux-clearbutton-mouse-over-input {
    background-position: 0 -12px;
}

.ext-ux-clearbutton-mouse-over-button {
    background-position: 0 -24px;
}

.ext-ux-clearbutton-mouse-down {
    background-position: 0 -36px;
}

.ext-ux-clearbutton-on {
    opacity: 1;
    visibility: visible;
    transition: opacity .35s linear;
    -webkit-transition: opacity .35s linear;
    -moz-transition: opacity .35s linear;
    -o-transition: opacity .35s linear;
    -ms-transition: opacity .35s linear;
    -khtml-transition: opacity .35s linear;
}

.ext-ux-clearbutton-off {
    opacity: 0;
    visibility: hidden;
    transition: opacity .35s linear, visibility .0s linear .35s;
    -webkit-transition: opacity .35s linear, visibility .0s linear .35s;
    -moz-transition: opacity .35s linear, visibility .0s linear .35s;
    -o-transition: opacity .35s linear, visibility .0s linear .35s;
    -ms-transition: opacity .35s linear, visibility .0s linear .35s;
    -khtml-transition: opacity .35s linear, visibility .0s linear .35s;
}