Homepage slider images cut off at top and bottom on mobile and desktop computers

I really enjoy the Sydney theme. However, I’m facing a little challenge at the moment.
I have the header slider with five images for slide across but the images don’t show completely as the top and bottom parts of the images are cut off.
Please, is there any CSS I need to include in my child theme css to make the images show completely in the slider without any part being cut off?
Here is an image sample of the slider with the menu.

Thanks so much for your kind respond.

Hello there,

You should enable responsive slide image through Dashboard > Appearance > Customize > Header area > Header Slider; scroll down until you get the "Slider mobile behavior" section and select “Responsive”. However this only applied on mobile screen. For larger screen, the slide image behaves to cover the entire screen area. As it’s proportionally scaled, the edge area overlap the slide container – our eyes see it being cut off.

If you wish to display chart date in the slide header, you should prepare a new image with an image editing program like Photoshop; use at least 1280 × 896 px document size (10 : 7 aspect ratio); put your chart in the middle, so it’ll look like this mug: https://unsplash.com/photos/uSQMmCAYRMM.

I hope this reply helps.