Full Background Image Resolution Very Bitmap-ie on Small Vie

Hi Support, I am working from a Full Background Image template for a web page, and in my online testing the image looks fine across viewport, device and screen size, but when I do real-world testing on my iPhone 7 (iOS 11), the background image I am using loses its resolution and becomes very "bitmap-ie" and overly pixelated. The image clarity is completely lost. How can I correct this? My original image size for the background image is: 985 x 750 px (72 dpi) Here's my page (test in production): http://gridinteractive.com/gma-2018/georgetown-bites.htm Here's how it looks in Quirktools on smaller viewports: http://quirktools.com/screenfly/#u=http%3A//gridinteractive.com/gma-2018/georgetown-bites.htm%23more&w=320&h=568&a=37&s=1 But compare on an actual smartphone to see the difference. Any help is greatly appreciated! Thank you! Eric Seattle, Washington  

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