This is a premium, single-file, production-ready solution. It uses Tailwind CSS for the layout engine, Lucide for iconography, and vanilla JavaScript for the reactive calculation logic. ```html Free Wallpaper Roll Calculator & Room Coverage Estimator

Wallpaper Roll Calculator

A precise, browser-based tool to determine your wallpaper requirements. Accurate, real-time calculations for any room dimension.

Ephemeral Mode: Data resets on page refresh.

Wallpaper & Room Specs

Wall Dimensions

Calculation Summary

Based on your provided dimensions

Total Surface Area 0 m²
Total Strips Required 0
Suggested Rolls 0

*Calculations assume standard vertical installation. Rounding up to the nearest whole roll. Always double-check measurements before purchasing.