Create initial landing page with user interest form

I would like to create a landing page using `index_2.html` at the root of the repository with the following elements.

# Navigation
* This is a landing page so no navigation is necessary for now.
* The main hero section should have the following tagline:
* Product Name: `dev++`
* Slogan: `The best way to Learn\nIs to Launch`
* Underneath the hero section a couple feature highlights (to be filled in later)
* Under the feature highlights a form with the following:
* Name
* Email
* Coding experience - slider with options 1 year, 5 years, 10 years, 20 years
* AI tools used for coding - checkboxes with options Chatbots (ChatGPT, Gemini), IDEs (Cursor, Windsurf), Coding Agents (Claude Code, Codex), Vibe coding (Lovable, v0, Replit)
* AI tool expertise - for each box checked, a slider with options (novice, intermediate, expert)
* A submit button which does basic form validation and POSTs the data which will go to a script that appends it to a Google Sheet.
* On submission, add a spinner icon after the text in the button, post to a URL, update the icon to a checkmark or exclamation point depending on if the response is 2xx.
* A Python function which writes the form data into a Google Sheet. This script will be hosted on a server capable of executing Python.