[FEATURE] Make the pages cover a full page

[Lemeri123]

Describe the bug.

Make the height of the Header page and the Venue page to cover a height of 100%.

Expected behavior

The pages should cover a total of 100% the height

Screenshots

How to Reproduce

1. Go to the headers page(landing page)
2. And also the Venue page and choose any location

🥦 Browser

None

👀 Have you checked for similar open issues?

• I checked and didn't find similar issue

🏢 Have you read the Contributing Guidelines?

• I have read the Contributing Guidelines

Are you willing to work on this issue ?

None

[github-actions]

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