The word "either" is meant to be used for two things, but the list contains 4 items. Proposing that "either" is replaced with "one of the following" for improved grammar.
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<p>
- The <code>container</code> is a simple utility element that allows you to <strong>center</strong> content on larger viewports. It can be used in any context, but mostly as a <strong>direct child</strong> of either:
+ The <code>container</code> is a simple utility element that allows you to <strong>center</strong> content on larger viewports. It can be used in any context, but mostly as a <strong>direct child</strong> of one of the following:
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<ul>
<li><code>navbar</code></li>