Add Studies dropdown with Scripture Index link; split nav triggers into hover+click

- Studies nav item is now a dropdown (same pattern as Episodes): hover to expand,
  click the label to navigate directly to /study
- Dropdown contains: All Studies (/study) and Scripture Index (/scripture)
- Episodes dropdown follows the same split pattern: label navigates, caret toggles
- Dropdown menus open on CSS :hover (desktop) and stay toggle-able on mobile
- v1.2.1

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.css

@@ -9438,36 +9438,55 @@
 }
 
 .nav-dropdown-trigger {
-  background: none;
-  border: none;
-  cursor: pointer;
-  padding: 0;
   display: flex;
   align-items: center;
-  gap: 0.25rem;
+  gap: 0;
+}
+
+.nav-dropdown-label {
   color: var(--brand-muted);
   font-family: inherit;
   font-weight: 500;
   letter-spacing: 0.06em;
   text-transform: uppercase;
   font-size: 0.96rem;
-  line-height: inherit;
+  text-decoration: none;
   transition: color 200ms;
+  line-height: inherit;
 }
 
-.nav-dropdown-trigger:hover,
-.nav-dropdown--open .nav-dropdown-trigger {
+.nav-dropdown-label:hover,
+.nav-dropdown--open .nav-dropdown-label {
   color: var(--brand-gold);
 }
 
+.nav-dropdown-caret {
+  background: none;
+  border: none;
+  cursor: pointer;
+  padding: 0 0 0 0.25rem;
+  color: var(--brand-muted);
+  font-size: 0.7em;
+  line-height: inherit;
+  transition: color 200ms;
+  opacity: 0.7;
+}
+
+.nav-dropdown-caret:hover,
+.nav-dropdown--open .nav-dropdown-caret {
+  color: var(--brand-gold);
+  opacity: 1;
+}
+
 .nav-dropdown-arrow {
   font-size: 0.7em;
   opacity: 0.7;
 }
 
 .nav-dropdown-menu {
+  display: none;
   position: absolute;
-  top: calc(100% + 0.75rem);
+  top: calc(100% + 0.5rem);
   left: 50%;
   transform: translateX(-50%);
   background: rgba(15, 15, 12, 0.98);
@@ -9479,6 +9498,11 @@
   box-shadow: 0 8px 24px rgba(0,0,0,0.5);
 }
 
+.nav-dropdown:hover .nav-dropdown-menu,
+.nav-dropdown--open .nav-dropdown-menu {
+  display: block;
+}
+
 .nav-dropdown-item {
   display: block;
   padding: 0.55rem 1.1rem;
@@ -9711,6 +9735,11 @@
     border-bottom: 1px solid rgba(201, 168, 76, 0.12);
   }
 
+  .nav-dropdown-label {
+    flex: 1;
+    padding: 0;
+  }
+
   .nav-dropdown-menu {
     display: none;
     position: static;
@@ -9723,6 +9752,10 @@
     min-width: 0;
   }
 
+  .nav-dropdown:hover .nav-dropdown-menu {
+    display: none;
+  }
+
   .nav-dropdown--open .nav-dropdown-menu {
     display: block;
   }