css loading

.loading {
    display: inline-block;
    width: 30px;
    height: 30px;
    border: 2px solid
rgba(0,0,0,.2 );
    border-top-color: rgba(0, 0, 0, 0.2);
border-radius: 50%;
border-top-color:
    rgba(0,0,0,.4 );
    animation: spin 1s ease-in-out infinite;
    -webkit-animation: spin 1s ease-in-out infinite;
    left: calc(50%);
    top: calc(50%);
    position: fixed;
    z-index: 1;
}