#overlay {
    position: fixed; /* Sit on top of the page content */
    display: none; /* Hidden by default */
    width: 100%; /* Full width (cover the whole page) */
    height: 100%; /* Full height (cover the whole page) */
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0,0,0,0.5); /* Black background with opacity */
    z-index: 9999999; /* Specify a stack order in case you're using a different order for other elements */
    cursor: pointer; /* Add a pointer on hover */
}
/* Center the loader */
#loader {
    position: absolute;
    left: 50%;
    top: 50%;
    z-index: 1;
    width: 150px;
    height: 150px;
    margin: -75px 0 0 -75px;
    border: 16px solid #f3f3f3;
    border-radius: 50%;
    border-top: 16px solid blue;
    border-bottom: 16px solid blue;
    width: 120px;
    height: 120px;
    -webkit-animation: spin 2s linear infinite;
    animation: spin 2s linear infinite;
}

@-webkit-keyframes spin {
    0% {
        -webkit-transform: rotate(0deg);
    }

    100% {
        -webkit-transform: rotate(360deg);
    }
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

/* Add animation to "page content" */
.animate-bottom {
    position: relative;
    -webkit-animation-name: animatebottom;
    -webkit-animation-duration: 1s;
    animation-name: animatebottom;
    animation-duration: 1s
}

@-webkit-keyframes animatebottom {
    from {
        bottom: -100px;
        opacity: 0
    }

    to {
        bottom: 0px;
        opacity: 1
    }
}

@keyframes animatebottom {
    from {
        bottom: -100px;
        opacity: 0
    }

    to {
        bottom: 0;
        opacity: 1
    }
}