Missing CSS in Front End Forms Using wp_editor

I developed a child theme where site visitors submit content (saved as draft posts) via a front end form that uses wp_editor() for the textarea field.

There seems to be some CSS missing with the editor in Text mode when using the editor for Insert/Edit Link – the screen shots below show the differences between the editor on the front end of the site vs the dashboard. This happens on another theme with a different parent theme.

I’ve poured through the link boxes in the web inspector and there are numerous differences in styles applied within the Insert/Edit link box (it works fine in visual editor mode).

To see this,

1. go to the form at https://daily.arganee.world/add/
2. Type some text, select, and click the link button

It should be obvious that the CSS is off; there is “Close” text off screen adjacent to the modal dismiss button in the bottom right; the text for the search overlaps the form elements.

Some screenshots to show the difference:

Link Editor on front end form https://www.dropbox.com/s/vnt0jv5w8593yy1/wp-editor-front-end.jpg?dl=0
Link Editor on back end https://www.dropbox.com/s/hf5p19izn1aj7zc/wp-editor-back-end.jpg?dl=0

The page I need help with: [log in to see the link]