.change-mobile-number,
.login-form {
    height: 0;
    opacity: 0;
    overflow: hidden;
    transition: all 1.5s ease-in-out;
}
    .change-mobile-number.active,
    .login-form.active {
        transition: all .5s ease-in-out;
        height: auto;
        opacity: 1;
    }
.overlayContainer {
    width: 100%;
    height: 100%;
    background-color: rgba(77, 133, 211, 0.8);
    display: block;
    position: fixed;
    z-index: 9999;
}
.centeredLoading {
    position: fixed;
    top: 50%;
    left: 50%;
    /* bring your own prefixes */
    transform: translate(-50%, -50%);
    z-index: 9999;
}