Go to Appearance > Menu to setup.
1. At level 1 menu item, click the “mega menu” button to start the mega menu builder. ( Note: You can only build mega menu at level 1 menu item)
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2.Then popup mega menu setting display, you can select options then select mega menu option.
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3.Then edit menu item level 2. Click “mega menu” button ton menu item lv2 to edit. Select “hide text” option and column width.
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4.Then edit menu item level 3. Click “mega menu” button ton menu item lv3 to edit. Slect column width and you can add content for item menu.
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Note: Mega menu is only visible on desktop devices, not on mobile devices.