refactor(/kubernetes/managed): Rebrand style and update to american english

[petesfrench]

Done

• Rebrand based on figma design
• Updated spelling to american english
• Some minor copy changes

QA

• Check out the demo
• Check it matches the design
• Check the content matches the copydoc

Issue / Card

Fixes https://warthogs.atlassian.net/browse/WD-12883

[webteam-app]

Demo

Jenkins

demos.haus

[petesfrench]

@mattea-turic Can you give this a design review please

[mattea-turic]

@petesfrench This looks pretty much perfect as is and I honestly don't have anything to add other than if you could:

• Add a hr for the "Kubernetes-as-a-service..." section on smaller screens
• And similarly, a hr for the "Managed IT services..." section – again, on smaller screens

Either way, I'm +1ing for design

Edit: @eliman11 lmk that there's a logo missing from the first "They trust us to run their k8s" section, which I've added here

[eliman11]

Thanks @petesfrench! Just a couple minor changes:

• Change to US spelling: minimise -> minimize in "99.9% guaranteed uptime. All cluster components are highly available and proactively monitored to minimize unplanned downtime."
• Could we add a h2 tag to the "They trust us to run their K8s" and "They trust us to run their K8s" headings for the logo cloud sections?

Feel free to add UX+1 once you've changed those! Thanks :)

[mtruj013]

LGTM! Just a few super minor comments. Also assumed that the index and what-is-kubernetes changes come from the updated base branch and won't be included in this pr once this is rebased, but lmk if you need me to look at changes there as well