Ok, I got this fixed in 2 seconds. I added the following code to your Custom CSS –
.flexible-widgets .widget {
clear: both;
/*overflow: hidden;*/
}
Either the clear: both or the overflow: hidden would fix it, but I just used clear: both for now and left the overflow commented out just in case you need to use that in the future.
If you want to see it or adjust the code you find it in Appearance > Customize > Additional CSS.
