Comprehensive PHP Website Repair

My PHP site is misbehaving on three fronts—front-end layout glitches, broken back-end features, and unstable MySQL connectivity. The visual theme and overall design should remain untouched; the goal is to bring everything back to full working order without redesigning anything.

You will have full FTP, cPanel/SSH, and database access, plus a staging sub-domain so fixes can be tested safely before we go live.

Key deliverables
• Front-end: restore proper page rendering, script loading, and cross-browser consistency.
• Back-end: debug and reinstate all existing admin functions (user management, order flow, email notifications, etc.).
• Database: resolve connection drops, clean up error-prone queries, and confirm reliable read/write operations.

Acceptance will be based on successful testing in staging: no visible errors, all features behaving as originally intended, and solid database connectivity under normal load. Please let me know your troubleshooting approach and an estimated timeline so we can get started right away.