404 page is a crucial enough part of a website. When a visitor is directed to the 404 page, it indicates that the post or page she/he is trying to access doesn’t exist. Each Jupiter X website template comes with a unique 404 page. You can customize it in case there are parts you want to remove or add. Since Jupiter X is an Elementor-based WordPress theme, you can customize the 404 page via the visual editor of Elementor.
To customize the 404 page in Jupiter X, go Pages -> All Pages. Find the 404 page and edit it with Elementor.

You will be directed to the Elementor editor after clicking the Edit with Elementor button above. To edit an existing widget, click the widget handle to turn it into an editing mode. You can also use the Navigator to ease your job. Clicking a widget on the Navigator will turn it into an editing mode.

Once the widget turned into an editing mode, you can go to the left panel to edit it. You can change the content (image, icon, text) on the Content tab and style the content on the Style tab. To set the margins, paddings, and other advanced settings, you can go to the Advanced tab.

To remove an existing widget, simply right-click the widget you want to remove and select Delete. To add a new widget, simply drag the widget you want to add from the left panel to the canvas area.

Click the UPDATE button on the bottom side of the left panel once you are done editing the page.
Creating a new 404 page
If you want to create a new 404 page rather than editing the existing one, you can also do so. Jupiter X itself offers several 404 page templates. To create a new 404 page, go Pages -> Add New. Give your 404 page a name and edit it with Elementor.

You can start creating the page by adding the widgets you want. In this example, we create the 404 page from a template. Click the folder icon on the canvas area to open the template library. Once the template library opens, go to the Blocks tab. Click the JUPITER X tab under the Blocks tab and search a 404 template you want to use and click the INSERT button to load it to the Elementor canvas.

As before, you can edit, remove, add a new widget. Once done editing, click the PUBLISH button to publish your page.
To apply the new 404 page you have just created, go to the theme customizer (Appearance -> Customize). Open the Pages block and select 404. Select the 404 page you have just created.

Click the Publish button to apply the change.