3d-dice/dice-box — reverse-engineered prompt

Build me a polished browser demo for a 3D dice roller that I can drop into a tabletop RPG or board game app. I want a full screen dice area with realistic 3D dice rolling, using the Dice Box library from this repo, and a simple control panel where I can type rolls like 2d20 or 2d6 plus 4 and press a button to roll.

Please show the total and individual dice results after the dice stop moving, include a clear button, and make it feel nice on desktop and mobile. Use the included assets correctly so it works after install, and add a simple theme or background so it looks like an actual dice tray instead of a blank page.

Keep it as a clean JavaScript app that’s easy to understand and modify. If you need exact setup details or config options, look up the current Dice Box docs online.