Improve the lighthouse scores by fixing issues

[ghoshbishakh]

• [x] Use font-display: swap;
• [ ] Think how to reduce JS and CSS loads. See if we can use some bundler to bundle all js and serve ourselves.
• [x] Use a video instead of a GIF
• [ ] Consider deferring css loads using async and defer. Test by changing network throttling to slow 3g.
• [ ] Fix accessibility issues
• [ ] Fix SEO issues