Complete #52, Optimize CSS, Reduce code duplication, Scrap templates; Massive refactor.

src/partials/_pane_nav.scss

@@ -3,17 +3,15 @@
 @use "nav_location";
 @use "nav_quick_links";
 
-.pane_nav {
+nav.pane {
+    grid-area: nav;
+
     --padding-mobile: 0.35rem;
 
-    margin: var(--spacing-large);
-
-    width: min-content;
     height: min-content;
 
     display: flex;
     flex-direction: column;
-    gap: var(--spacing-medium);
 
     position: sticky;
     top: var(--spacing-large);
@@ -27,14 +25,12 @@
 }
 
 @media only screen and (max-width: 500px) {
-    .pane_nav {
+    nav.pane {
         width: calc(
-            calc(50% - var(--spacing-large) + var(--spacing-small)) *
-                2
+            calc(50% - var(--spacing-large) + var(--spacing-small)) * 2
         );
 
         background-color: var(--background-2);
-        border-radius: var(--border-radius-leaf);
         padding: 0 var(--spacing-small);
 
         .nav_menu,
@@ -48,11 +44,11 @@
         }
     }
 
-    .pane_nav > #toggle:checked {
-        + .header {
+    nav.pane > #toggle:checked {
+        + .nav_header {
             color: var(--highlight-hover);
 
-            + .nav_menu {
+            + .menu {
                 display: grid;
 
                 + .location + .quick_links {