Auto image size to mobile with a custom liquid image

[MilesRobert]

How to resize custom liquid image ( any size ) to mobile. I only have a code for gifs but I need for images.

This is how it looks now.

website url: https://milehac.com/products/1pcs-airplane-car-neck-pillow-travel-comfy-sleep-orthopedic-neck-pillow-for-neck-pain-v-c-shape-no-inflatable-back-pain-support