Update to Universal Login themes doc

[BcnCarlos]

Description

Update to Universal Login themes and flexible identifiers doc and 2 new images

References

Docs-5625

Testing

Checklist

• I've read and followed CONTRIBUTING.md.
• I've tested the site build for this change locally.
• I've made appropriate docs updates for any code or config changes.
• I've coordinated with the Product Docs and/or Docs Management team about non-trivial changes.

[mintlify]

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Project	Status	Preview	Updated
auth0	🟢 Ready	View Preview	Sep 10, 2026, 1:41 PM

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[mintlify]

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Project	Status	Preview	Updated
auth0-docs-dev	🟢 Ready	View Preview	Sep 10, 2026, 1:41 PM

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[mintlify]

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Project	Status	Preview	Updated
auth0-docs-staging	🟢 Ready	View Preview	Sep 10, 2026, 1:41 PM

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[github-actions]

Summary

Status	Count
🔍 Total	21
🔗 Unique	20
✅ Successful	17
⏳ Timeouts	0
🔀 Redirected	0
👻 Excluded	3
❓ Unknown	0
🚫 Errors	1
⛔ Unsupported	0

Errors per input

Errors in main/docs/authenticate/database-connections/activate-and-configure-attributes-for-flexible-identifiers.mdx

• [ERROR] </docs/api/management/v2/tenants/patch-settings#body-country-codes-one-of-0> (at 86:76) | Cannot find fragment

Full Github Actions output

Run on commit e845f4a.