.w3-app-color, .w3-hover-app-color {
    color: #fff !important;
    background-color: #2196F3 !important;
}

.w3-hover-app-color {
    -webkit-transition: background-color .3s,color .15s,box-shadow .3s,opacity 0.3s;
    transition: background-color .3s,color .15s,box-shadow .3s,opacity 0.3s;
}