.ajaxnavigation-loader {
    display: block;
    width: 1em;
    height: 1em;
    font-size: 18px;
    border: 2px solid;
    border-top-color: transparent;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
    border-radius: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    margin: -0.5em 0 0 -0.5em;
    -webkit-animation: ajaxnav-spin .6s linear infinite;
    -moz-animation: ajaxnav-spin .6s linear infinite;
    animation: ajaxnav-spin .6s linear infinite;
}
.header-button .ajaxnavigation-loader{
    font-size: 24px;
    border-width: 4px;
}

@-webkit-keyframes ajaxnav-spin {
    from {
        -webkit-transform: rotate(0deg);
    }
    to {
        -webkit-transform: rotate(360deg);
    }
}

@-moz-keyframes ajaxnav-spin {
    from {
        -moz-transform: rotate(0deg);
    }
    to {
        -moz-transform: rotate(360deg);
    }
}
@keyframes ajaxnav-spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}