When I set the flex-direction value of .main-header the children of .main-nav are in a row not a column. So I was wondering if the children of flex-containers that are in flex-containers never get affected by the flex-container declarations of the parent container of their parent container.
<header class="main-header">
<h1 class="name"><a href="#">Best City Guide</a></h1>
<ul class="main-nav">
<li><a href="#">ice cream</a></li>
<li><a href="#">donuts</a></li>
<li><a href="#">tea</a></li>
<li><a href="#">coffee</a></li>
</ul>
</header><!--/.main-header-->
@media (min-width: 769px) {.main-header,.main-nav { display: flex;}
.main-header { flex-direction: column; align-items: center;}}