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    z-index: 165;
    width: 180px;
    height: 180px;
    opacity: 1;
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    border-radius: 0px;
    margin-left: 100px;
    margin-top: 24px;
    position: relative;
    background: transparent url("../../images/covid-plan-regreso.jpg") no-repeat left top;
    background-size: cover;
}
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    z-index: 166;
    width: 180px;
    height: 333px;
    opacity: 1;
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    border-radius: 0px;
    margin-left: 100px;
    margin-top: 24px;
    position: relative;
    background: transparent url("../../images/covid-medidas-prevencion.jpg") no-repeat left top;
    background-size: cover;
}
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    z-index: 167;
    width: 180px;
    height: 333px;
    opacity: 1;
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=100)";
    filter: alpha(opacity=100);
    border-radius: 0px;
    margin-left: 100px;
    margin-top: 24px;
    position: relative;
    background: transparent url("../../images/covid-desarrollo-clases.jpg") no-repeat left top;
    background-size: cover;
}