feat: implement epub service, navigation service, and global error boundary with updated reader UI layouts

src/NexusReader.UI.Shared/Components/Molecules/IntelligenceToolbar.razor.css

@@ -1,16 +1,18 @@
 .intelligence-toolbar {
     width: 50px;
     height: 100%;
-    background: #1a1a1a;
-    border-right: 1px solid rgba(255, 255, 255, 0.05);
+    background: #080808;
+    border-right: 1px solid rgba(255, 255, 255, 0.03);
     display: flex;
     flex-direction: column;
     justify-content: space-between;
-    padding: 1rem 0;
+    padding: 1.5rem 0;
     align-items: center;
     z-index: 20;
+    box-shadow: inset -2px 0 10px rgba(0,0,0,0.5);
 }
 
+
 .toolbar-top, .toolbar-middle, .toolbar-bottom {
     display: flex;
     flex-direction: column;
@@ -20,29 +22,46 @@
 .toolbar-item {
     background: none;
     border: none;
-    color: #666;
+    color: #444;
     cursor: pointer;
-    padding: 8px;
+    width: 34px;
+    height: 34px;
     display: flex;
     align-items: center;
     justify-content: center;
-    transition: all 0.2s ease;
-    border-radius: 4px;
+    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
+    border-radius: 8px;
+    position: relative;
 }
 
 .toolbar-item:hover {
-    color: #fff;
-    background: rgba(255, 255, 255, 0.05);
+    color: var(--nexus-neon);
+    background: rgba(0, 255, 153, 0.05);
 }
 
 .toolbar-item.active {
     color: var(--nexus-neon);
+    background: rgba(0, 255, 153, 0.08);
+}
+
+.toolbar-item.active::after {
+    content: '';
+    position: absolute;
+    right: -2px;
+    top: 25%;
+    height: 50%;
+    width: 3px;
+    background: var(--nexus-neon);
+    box-shadow: 0 0 8px var(--nexus-neon);
+    border-radius: 2px;
 }
 
 .toolbar-item.focus-active {
-    filter: drop-shadow(0 0 5px var(--nexus-neon));
+    color: var(--nexus-neon);
+    filter: drop-shadow(0 0 8px var(--nexus-neon));
 }
 
+
 .rotate-180 {
     transform: rotate(180deg);
 }