Refactor Undefined Class Usage in SubNavigation

### Problem
The [`SubNavigation`](https://github.com/diplodoc-platform/components/blob/master/src/components/SubNavigation/SubNavigation.scss) component in diplodoc-platform/components uses the `.dc-root_wide-format` class, which isn't defined in the current library. This can cause styling issues.

### Solution
Move the styles for `.dc-root_wide-format` from the diplodoc-platform/components package to the [diplodoc-platform/client](https://github.com/diplodoc-platform/client) package.

### Tasks
1. Identify Usage: Find all occurrences of `.dc-root_wide-format` in `SubNavigation`.
2. Move Styling: Transfer these styles to the client package.
3. Update References: Modify any references in `SubNavigation` to use the relocated styles.
4. Testing: Ensure the component works and is styled correctly post-changes.

### Goal
Ensure `SubNavigation` maintains functionality and appearance with appropriately defined styles.