Splash pages are not very straightforward to do because Joomla always tries to load it's own pages first. In order to avoid this, we can use a module called SplashR:
Install SplashR
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Go to the SplashR listing on the Joomla Extensions Directory and click Download.
Go to the administrator area of your site then Extensions >> Install/Uninstall, click Browse and upload the module file.
Then go to Extensions >> Module Manager and open up the SplashR module.
Edit the Module Settings
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There are several settings you'd need to change here:
- Splash URL: the page you want to use for the splash screen.
- Splash Title: telling people what site they're visiting.
- Autohide Timer: setting this to 0 forces people to click through to your main site.
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Once you enable the module, visitors to your site will see a screen like the one above. There will be a black bar across the top of the screen and a button in the top-right corner.
If you'd like to edit the design of the splash controls, go to this folder to replace the images: /modules/mod_splashr/assets/images/