Create Landing Page with Styling
## Description
Landing Page and styling (ie from MyCapp Form Builder).
[Figma proto link](https://www.figma.com/proto/aIqgeUBRzZcMNKQPxUNo8f/Jackdaw-replacement?node-id=135-1024&t=OK7YR7UnwaZ5ts0r-0&scaling=min-zoom&content-scaling=fixed&page-id=0%3A1&starting-point-node-id=135%3A1024&show-proto-sidebar=1)
[Figma design link](https://www.figma.com/design/aIqgeUBRzZcMNKQPxUNo8f/Jackdaw-replacement?node-id=135-1024&node-type=frame&t=2poXr4gau1v8cKv0-0)
See https://gitlab.developers.cam.ac.uk/groups/uis/devops/-/epics/175
## Task List
- [ ] Check with DA MyCApp code if there is style/components that can be reused
- [ ] Use MUI Theming should be used so normal react/html components get styling rather than styling each separately
- [ ] Use Dark mode support, if provided for free but not to put a lot of effort in it ("stretch goal")
- [ ] Should have Header and Footer separate components to be included in all pages
- [ ] Check Figma templates show how mobile devices should be handled and replicate. If not, take best guess/practice (or go back Jonathan)
## Acceptance criteria
- [ ] Visually matches the style in Figma (and MyCapp Form Builder)
- [ ] Works responsively across size ranges (e.g. MUI's xs, sm, md, ...)
- [ ] Re-use components wherever practical
- [ ] On clicking 'Get your University IT account' button, throws up an alert
- [ ] Meets [WCAG 2.2 Guidelines](https://www.gov.uk/service-manual/helping-people-to-use-your-service/understanding-wcag)
- [ ] HTML Links are operational
issue