Text input boxes in a table are extending beyond the width of the table

Can anyone explain why my text input boxes, which are inside a table, are allowed to extend beyond the width of the table on this page when I reduce the width of my browser window (see screenshot attached)?...

https://www.fearlessgirl.us/purchase-a-reproduction/

I want the table to stay within the floating <div> (which makes up its column), and the input boxes to stay within the table cells.

Screenshot
Thank you.
Brad BansnerWeb DeveloperAsked:
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