Check out example codes for "how to diagnose horizontal scroll that will not go away on mobile site". It will help you in understanding the concepts better.

Code Example 1

body {
    overflow-x: hidden;
    width: 100%;
}

<meta name="viewport" content="user-scalable=no, width=device-width, initial-scale=1.0" />
<meta name="apple-mobile-web-app-capable" content="yes" />

Code Example 2

<meta name="viewport" content="user-scalable=0;"/>

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