chore: updated sponsor logo

Author: panva

README.md

@@ -61,7 +61,13 @@ package.json since breaking changes may be introduced as part of these version u
 
 ## Sponsor
 
-[<img height="65" align="left" src="https://cdn.auth0.com/blog/github-sponsorships/brand-evolution-logo-Auth0-horizontal-Indigo.png" alt="auth0-logo">][sponsor-auth0] If you want to quickly add OpenID Connect authentication to Node.js apps, feel free to check out Auth0's Node.js SDK and free plan. [Create an Auth0 account; it's free!][sponsor-auth0]<br><br>
+<picture>
+  <source media="(prefers-color-scheme: dark)" srcset="./sponsor/Auth0byOkta_dark.png">
+  <source media="(prefers-color-scheme: light)" srcset="./sponsor/Auth0byOkta_light.png">
+  <img height="65" align="left" alt="Auth0 by Okta" src="./sponsor/Auth0byOkta_light.png">
+</picture> 
+
+If you want to quickly add OpenID Connect authentication to Node.js apps, feel free to check out Auth0's Node.js SDK and free plan. [Create an Auth0 account; it's free!][sponsor-auth0]<br><br>
 
 ## Support
 
@@ -305,7 +311,7 @@ See [Customizing (docs)][documentation-customizing].
 [feature-iss]: https://www.rfc-editor.org/rfc/rfc9207.html
 [passport-url]: http://passportjs.org
 [npm-url]: https://www.npmjs.com/package/openid-client
-[sponsor-auth0]: https://a0.to/try-auth0
+[sponsor-auth0]: https://auth0.com/signup?utm_source=external_sites&utm_medium=panva&utm_campaign=devn_signup
 [support-sponsor]: https://github.com/sponsors/panva
 [documentation]: https://github.com/panva/node-openid-client/blob/main/docs/README.md
 [documentation-issuer]: https://github.com/panva/node-openid-client/blob/main/docs/README.md#issuer