Building a landing page like Helloweather's site?

Hi all,
I'm at a place now where I'm 75% done with building a MVP of my first iOS app, with plans to ship it in the next couple months (I'm a self-taught iOS developer on the side). So, I'm starting to think about building a website for the app.

I looked around and I really like the design and simplicity of the Hello Weather app's landing page (Helloweather.com). It's clean, simple, with a friendly "cartoonish" vibe that are similar to the feel I want my app and landing page to have.

Any advice on how I would get started? I don't know web development, and I think I should focus all my time on the MVP instead of messing around trying to build a website myself.

My current plan is:

• I looked at the metadata for Helloweather.com, but I didn't see any signs of a template or website builder they used. I'm guessing it's a custom site.
• There are some templates on Wix and Unbounce that have a similar cartoonish look. Perhaps I can find a freelance web developer on Upwork, point them to the Wix template and the Helloweather.com example, and ask them to build the site as quickly as possible? If so, what might be a ballpark estimate of how much it might cost to build something similar to the Helloweather site? $500? $2000? More? I'm guessing I wouldn't need the most experienced developer in the world, as it's relatively straightforward and it's the design that sets the Helloweather site apart. But let me know if I'm mistaken.

Thanks in advance!