Resize slider for mobile version of website

Hi, I have a slider/promotional image set up for my website, which you can see under the menu bar HERE.

I'm happy with this and how it looks/works on the desktop version of the site, but as soon as you can view the page in mobile, it cuts off most of the images, due to the size of them.

My question is does anyone have an idea on how I can get the slider to resize and fit the screen when looking on a mobile? Basically I'd like it to scale instead of cropping.

Thank you!

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Code (markup):

Resize slider for mobile version of website

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