<script>
$(document).ready(function(){
$('#rec207334530, #rec207335831, #rec207337764, #rec207339210, #rec207342944').addClass('chooseblk').hide();
function getRandomInt(max) { return Math.floor(Math.random() * Math.floor(max));};
var blkSts = getRandomInt($('.chooseblk').length);
$('.chooseblk:eq('+blkSts+')').show();
});
</script>
<script>
$(document).ready(function(){
$('#rec371775673, #rec371775713, #rec371775743').addClass('chooseblk').hide();
function getRandomInt(max) { return Math.floor(Math.random() * Math.floor(max));};
function showRandomBlock(){
let blkSts = getRandomInt($('.chooseblk').length);
$('.chooseblk').hide();
$('.chooseblk:eq('+blkSts+')').show();
};
showRandomBlock();
$('a[href="#randowblk"]').click(function(e) {e.preventDefault();showRandomBlock()});
});
</script>