My Shopify store is ready to level-up and I want to roll out three key upgrades at the same time: advanced product filtering, on-site customer reviews with ratings, and a smooth integration with selected third-party services (e.g., email marketing and fulfilment apps). I don’t have polished mock-ups yet, so part of the job is shaping the UX/UI to fit my existing theme while keeping performance fast and the look on-brand. Here’s what success looks like for me: • Product filtering that works out of the box on collection pages (price range slider, tags, colour/size swatches) and remains compatible with future theme updates. • A review system that lets shoppers leave star ratings, photos and verified-purchase badges, displayed in a way that blends naturally with the product page layout. • Seamless API-based connections to the third-party tools I already use, with clear settings inside the Shopify admin so I can manage everything without code. All work needs to be done natively in Shopify (Liquid, Theme App Extensions, Javascript) and tested on both desktop and mobile before hand-off. Please package the final deliverable so I can install or merge it into my live theme with minimal downtime, and include concise documentation explaining any custom sections, snippets, or metafields you create.