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Now, when someone visits your Google Sites site on one of these devices, the width of the site will be adjusted to match the device's width, and many other details, such as sidebars and dropdown links, will be tweaked to look good on a smaller screen.
To enable the feature, go to General Settings - More Actions - Manage Site and click on "Automatically adjust site for mobile phones". You can also preview your page from your desktop by choosing More Actions - Preview As Viewer (Mobile).
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