Add mega menu, filter selects, and technical specs table.

Improve navigation with grouped category mega menu, polish product filters, and render technical values as a table instead of raw JSON.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/globals.css

@@ -185,6 +185,28 @@ img {
   border-color: var(--brand);
 }
 
+.field-select-wrap {
+  position: relative;
+}
+
+.field-select-wrap::after {
+  content: "▾";
+  position: absolute;
+  inset-inline-end: 0.9rem;
+  top: 50%;
+  transform: translateY(-50%);
+  pointer-events: none;
+  color: var(--muted);
+  font-size: 0.75rem;
+  line-height: 1;
+}
+
+.field-select {
+  appearance: none;
+  padding-inline-end: 2.25rem;
+  cursor: pointer;
+}
+
 .btn-secondary {
   display: inline-flex;
   align-items: center;