Check out example codes for "gap above nav bar html". It will help you in understanding the concepts better.

Code Example 1

<!-- make a empty div and style it (css) with background color : <your nav bar color>,
top : 0, left : 0. place it just below the nav bar. -->
<div class="whitespace"></div>
<!-- style (css) -->
.whitespace {
	width: 1300px;
  	height: 100px;
  	top: 0px;
  	left: 0px;
  	background: #FFFFFF;
  	position: fixed;

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