implement landing page with placeholder queries

[navi-arneja]

Designs: https://www.figma.com/file/ix7iiBwB26W8iSxQ9u8im6/Arronax-Landing-Page?node-id=0%3A1

Design spec: https://docs.google.com/document/d/1IE_KBCYuORUKEYUed0xyVUjvb2qEgyV3EwGYAWRhSwg/edit?usp=sharing

Queries will eventually be video animations. For now, we can put in placeholder squares where the videos will go.