It’s all contained within a custom section where the “data” is added directly within the theme customizer as blocks! (Query parameters handled in the backend with JS and liquid)Reach out anytime! Admin@shopifyartisans.com  

Take a look at at the functionality of this custom page I built. Similar to what you're looking for I believe. (Here I have nested state and country in the example link) Let me know If I can help!

Take a look at at the functionality of this custom page I built. Similar to what you're looking for I believe. Let me know If I can help!

Take a look at at the functionality of this custom page I built. Similar to what you're looking for I believe. Let me know If I can help.