Check out example codes for "how to set viewport in html". It will help you in understanding the concepts better.

Code Example 1

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Code Example 2

// viewport for web responsive design.. 

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Code Example 3

<meta name="viewport" content="width=device-width, initial-scale=1">

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