Update nav: book icon logo, add Q&A link, remove Home link

src/App.css

@@ -28,17 +28,28 @@
   justify-content: space-between;
 }
 
-.header-ornament {
-  font-family: var(--brand-font-body);
-  color: var(--brand-gold);
-  letter-spacing: 10px;
-  font-size: 0.85rem;
-  opacity: 0.6;
+.header-logo {
+  display: flex;
+  align-items: center;
+  text-decoration: none;
+  transition: opacity 200ms;
+  flex-shrink: 0;
+  opacity: 0.82;
+}
+
+.header-logo:hover {
+  opacity: 1;
+}
+
+.header-logo-img {
+  height: 52px;
+  width: auto;
+  display: block;
 }
 
 .header-nav {
   display: flex;
-  gap: 1.75rem;
+  gap: 1.5rem;
   align-items: center;
 }
 
@@ -63,7 +74,7 @@
   font-weight: 500;
   letter-spacing: 0.06em;
   text-transform: uppercase;
-  font-size: 1.02rem;
+  font-size: 0.96rem;
   transition: color 200ms;
 }
 
@@ -3024,8 +3035,8 @@
     font-size: 1.2rem;
   }
 
-  .header-ornament {
-    display: none;
+  .header-logo-img {
+    height: 40px;
   }
 
   .admin-stats-grid,