/*
 initialize rotation key frames,  
*/
@keyframes kf_spinner {
    to {
        transform: rotate(360deg)
    }
}
 
/*
The page overlay DIV, you can style it as you like, 
*/
#page-overlay {
    /*
    basic styles
    */
    text-align: center;
    color: #acb8ab;
    padding-top: 10px;
    font-size: .7em;
    display: block;
    background-color: #fefefe;
     
    /*
    important to work properly
    */
    width: 100%;
    height: 100%;
    position: fixed;
    top: 0;
    right: 0;
    left: 0;
    bottom: 0;
    z-index: 999999999999;/* highest top level layer */
     
    /*
    required for fade-out/fade-in animation effect
    */
    -webkit-transition: opacity 1s ease-in-out;
    -moz-transition: opacity 1s ease-in-out;
    -ms-transition: opacity 1s ease-in-out;
    -o-transition: opacity 1s ease-in-out
}
 
/*
show our loading layer
*/
#page-overlay.loading {
    opacity: 1;
    visibility: visible
}
 
/*
hide our loading layer
*/
#page-overlay.loaded,
#page-overlay>span {
    opacity: 0
}
 
/*
create the animated spinner
*/
#page-overlay.loading:before {
    /*
    required to work
    */
    content: '';
    box-sizing: border-box;
    position: absolute;
 
    /*
    centering the spinner on the page
    */
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin-top: -10px;
    margin-left: -10px;
    border-radius: 50%;
 
    /*
    create the spinner with css, no image required 🙂
    */
    border-top: 2px solid #acb8ab;
    border-right: 2px solid transparent;
 
    /*
    animate the spinner
    */
    animation: kf_spinner .6s linear infinite
}