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/* fix vertical when not overflow
call fullscreenFix() if .fullscreen content changes */
function fullscreenFix(){
    var h = $('body').height();
    // set .fullscreen height
    $(".content-holder").each(function(i){
        if($(this).innerHeight() <= h){
            $(this).closest(".fullscreen").addClass("not-overflow");
        }
    });
}
$(window).resize(fullscreenFix);
fullscreenFix();

/* resize background images */
function backgroundResize(){
    var windowH = $(window).height();
    $(".background").each(function(i){
        var path = $(this);
        // variables
        var contW = path.width();
        var contH = path.height();
        var imgW = path.attr("data-img-width");
        var imgH = path.attr("data-img-height");
        var ratio = imgW / imgH;
        // overflowing difference
        var diff = parseFloat(path.attr("data-diff"));
        diff = diff ? diff : 0;
        // remaining height to have fullscreen image only on parallax
        var remainingH = 0;
        if(path.hasClass("parallax")){
            var maxH = contH > windowH ? contH : windowH;
            remainingH = windowH - contH;
        }
        // set img values depending on cont
        imgH = contH + remainingH + diff;
        imgW = imgH * ratio;
        // fix when too large
        if(contW > imgW){
            imgW = contW;
            imgH = imgW / ratio;
        }
        //
        path.data("resized-imgW", imgW);
        path.data("resized-imgH", imgH);
        path.css("background-size", imgW + "px " + imgH + "px");
    });
}
$(window).resize(backgroundResize);
$(window).focus(backgroundResize);
backgroundResize();

<div class="fullscreen background" data-img-width="1600" data-img-height="1064">
    <div class="content-wrapper">
        <div class="content-holder">
            Centered content
        </div>
    </div>
</div>

html, body {
    /* give this to all tags from html to .fullscreen */
    height:100%;
}
.fullscreen,
.content-wrapper {
    width:100%;
    min-height:100%;
}
.not-fullscreen,
.not-fullscreen .content-wrapper,
.fullscreen.not-overflow,
.fullscreen.not-overflow .content-wrapper {
    height:100%;
    overflow:hidden;
}

/* content centering styles */
.content-wrapper {
	display:table;
}
.content-holder {
	display:table-cell;
    position:relative;
	vertical-align:middle;
	text-align:center;
}

/*WooCommerce*/
.woocommerce #content div.product div.thumbnails a, .woocommerce div.product div.thumbnails a, .woocommerce-page #content div.product div.thumbnails a, .woocommerce-page div.product div.thumbnails a{
	margin-bottom: 3.8%;
}