The HTML for each slideshow is just an unordered list of images. NO radio, checkboxes, labels, links or buttons.

90% of the stylesheet is shared by all three slideshow, with just 10% to resize the slideshows for the different aspect ratios of the images.

All the arrows, buttons and slide action are controlled using pseudo element. See Carousels with CSS

For Firefox I have shown the bottom scrollbar and it is possible to scroll the slides left or right. In Firefox this is done by holding the shift key and using the mouse wheel.