Update Assistant styling

[zenoachtig]

• Introduce a new subtle gradient to the Assistant window
• Simplify Assistant empty state
• Use full-length AI sidebar style for all sites
• Restyle suggested / follow-up questions
• Use ScrollContainer for the Assistant window, giving scroll buttons and faded edges
• Rework intro & exit animations for all elements of the Assistant, using subtle blurs
• Add dark mode to Embed window
• Update layouts to no longer assume site background, which allows the Embed window to have a translucent background
• Update Embed to no longer pass trademark itself but read it from the global AI context

CleanShot.2025-11-17.at.13.57.25.mp4

CleanShot.2025-11-17.at.14.00.21.mp4

[changeset-bot]

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Latest commit: b857123

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[github-actions]

Summary of the deployments:

Version	URL	Status
Vercel	https://gitbook-v2-b74etdky9-gitbook.vercel.app	✅
Cloudflare	https://f9a0cfc9-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	2v	2c
GitBook	https://gitbook-v2-b74etdky9-gitbook.vercel.app/url/gitbook.com/docs	https://f9a0cfc9-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://gitbook-v2-b74etdky9-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://f9a0cfc9-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

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Build	Status	Details	Updated (UTC)
customers-v2 (Inspect)	👍 Changes approved	3 changed, 4 removed, 1 failure	Nov 24, 2025, 11:18 AM
v2-cloudflare (Inspect)	👍 Changes approved	5 changed, 2 failures	Nov 24, 2025, 11:22 AM
v2-vercel (Inspect)	👍 Changes approved	8 changed, 2 failures	Nov 24, 2025, 11:22 AM