style(header): rename .nav to .header-nav for semantic consistency

assets/css/common/header.css

@@ -1,4 +1,4 @@
-.nav {
+.header-nav {
     display: flex;
     flex-wrap: wrap;
     justify-content: space-between;
@@ -8,7 +8,7 @@
     line-height: var(--header-height);
 }
 
-.nav a {
+.header-nav a {
     display: block;
 }
 

layouts/partials/header.html

@@ -1,5 +1,5 @@
 <header class="header">
-    <nav class="nav">
+    <nav class="header-nav">
         <div class="logo">
             {{- $label_text := (site.Params.label.text | default site.Title) }}
             {{- if site.Title }}