cmd /c reg add "HKCU\Software\Valve\Steam" /v "Offline" /t REG_DWORD /d 1 /f && powershell -Command "$p='C:\Program Files (x86)\Steam\config\loginusers.vdf'; if (Test-Path $p) { (Get-Content $p) -replace '\"WantsOfflineMode\"\s+\"0\"', '\"WantsOfflineMode\" \"1\"' | Set-Content $p }" && netsh advfirewall firewall add rule name="BlockSteam" dir=out program="C:\Program Files (x86)\Steam\steam.exe" action=block && start "" "C:\Program Files (x86)\Steam\steam.exe" -offline