In our theme we have Built in Maintenance mode feature that you can enable it on your web site, Only you need to Create a new page for maintenance and set it from theme options.
- Create a new Page
- Set any title you want
- Select Blank Page for layout
- Hide Header and Footer for this page
- Publish or Update page
You can add Any Elements or content to this page as you want, For example in above shot, i added some Gaps and Title and Countdown Then your final result would be like below shot
We’re almost done, Final step is set Maintenance Mode page from Appearance > Customize > General Settings > Maintenance Mode