fix: white background when content overflows viewport

[adi-ray]

Fixes #3563

Changes: Changed the height property to allow the container to grow with content while maintaining min-height: 100vh.

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I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123
• meets the standards outlined in the accessibility guidelines