Disable opacity on specific images

I need to disable the opacity on hover for specific images on my page.
In the example the three books images get sticky on top but, hovering the mouse over, makes them transparent, so the result is a mess.

Is there any class, like for example “colorbox-off” to remove the effects, without disabling them on all my website?

Thanks.

• This topic was modified 4 years, 4 months ago by Lock.

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