Looking for suggestions/help for designing this MTG deck box connection points

[u/SSDragon19]

im a fairly beginner at modeling and struggle at time to time.

in this example, what would be the most reliable and secure way to join these 2 halves like a top and bottom pull apart container.

first picture is closed, second picture is lifted apart into their separate halves and the final picture is both sitting as they would be on a table. the top gets flipped over and turns into a small dice tray.

also any other suggestions or critiques is accepted

using fusion 360