KubeWeekly section is unreadable in dark mode

[killjoycircuit]

This is a Bug Report

Problem:
The KubeWeekly newsletter signup text is unreadable in dark mode as it shows black text on a dark background.

Proposed Solution:
Add dark mode styles for the KubeWeekly section

Page to Update:
https://kubernetes.io/...

[k8s-ci-robot]

This issue is currently awaiting triage.

SIG Docs takes a lead on issue triage for this website, but any Kubernetes member can accept issues by applying the triage/accepted label.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[killjoycircuit]

/assign