Mobile Content Visibility Fix

My site loads instantly on desktop, yet on iPhones the first screen appears blank until the user scrolls. I need that initial viewport to render the content automatically so the experience feels seamless.

The problem is reproducible on multiple iOS devices, so I suspect a Safari-specific quirk in the way the page is painted—possibly tied to CSS overflow, position-fixed elements, or a JavaScript listener that waits for a scroll event before revealing content. There is no issue on Android or desktop browsers.

Your task is to pinpoint the exact cause and implement a clean fix that requires no extra action from visitors. I am happy to grant temporary access to the repository and staging server; the live site runs on standard HTML, CSS, a splash of vanilla JavaScript, with no heavy frameworks in play.

To move forward, briefly outline similar iOS rendering bugs you have solved and the techniques you used. I am after proven experience rather than a lengthy proposal. Once the fix is deployed and verified on the latest iOS Safari, the job is complete.