<body>
<header id="siteHeader">
<nav id="siteNavigation">
<img id="siteLogo" width="225" height="50" />
<div class="parentCategory">Main Series ▾</div>
<div class="parentCategory">Compilation of FFVII ▾</div>
<div class="parentCategory">Other Game Series ▾</div>
<div class="parentCategory">Standalone Games ▾</div>
<div class="parentCategory">Chocobo Games ▾</div>
<div class="parentCategory">Media ▾</div>
<div class="parentCategory">Collections & Other Info ▾ </div>
<form id="headerSearch" action="/site-search" method="get">
<input type="image" src="/Images/Search.svg" alt="Submit" width="24" height="24" />
<input type="text"name="query" />
</form>
</nav>
</header>
</body>
body{
display: grid;
font-family: DM Sans;
grid-template-areas: "siteHeader siteHeader" "sectionNavigation main" "sectionNavigation footer";
grid-template-columns: var(--sectionNavigationWidth) 1fr;
grid-template-rows: 3.5rem 1fr;
margin: 0 auto;
max-width: 1920px;
min-height: 100vh;}
#siteHeader{
grid-area: siteHeader;
position: sticky;
padding: 0.1rem;
top: 0;
/*white-space: nowrap;*/}
#siteNavigation{display: flex;}
#sectionNavigation{
grid-area: sectionNavigation;
padding: 0.5rem;}
.parentCategory{
align-self: center;
padding-left: 1.25rem;
text-align: center;
text-transform: uppercase;}
<body>
<header id="siteHeader">
<nav id="siteNavigation">
<img id="siteLogo" width="225" height="50" />
<div class="parentCategory">Main Series ▾</div>
<div class="parentCategory">Compilation of FFVII ▾</div>
<div class="parentCategory">Other Game Series ▾</div>
<div class="parentCategory">Standalone Games ▾</div>
<div class="parentCategory">Chocobo Games ▾</div>
<div class="parentCategory">Media ▾</div>
<div class="parentCategory">Collections & Other Info ▾ </div>
<form id="headerSearch" action="/site-search" method="get">
<input type="image" src="/Images/Search.svg" alt="Submit" width="24" height="24" />
<input type="text"name="query" />
</form>
</nav>
</header>
</body>
body{
display: grid;
font-family: DM Sans;
grid-template-areas: "siteHeader siteHeader" "sectionNavigation main" "sectionNavigation footer";
grid-template-columns: var(--sectionNavigationWidth) 1fr;
grid-template-rows: 3.5rem 1fr;
margin: 0 auto;
max-width: 1920px;
min-height: 100vh;}
#siteHeader{
grid-area: siteHeader;
position: sticky;
padding: 0.1rem;
top: 0;
/*white-space: nowrap;*/}
#siteNavigation{display: flex;}
#sectionNavigation{
grid-area: sectionNavigation;
padding: 0.5rem;}
.parentCategory{
align-self: center;
padding-left: 1.25rem;
text-align: center;
text-transform: uppercase;}