ui: hide tab text labels on mobile for /my and /p/ pages

- Add CSS media query to hide .tab-label on screens ≤768px
- Adjust tab padding and gap for mobile to show only icons
- Saves space on mobile for highlights, bookmarks, reads, links, writings tabs
- Affects Me, Profile, and Explore components

src/styles/components/me.css

@@ -75,6 +75,18 @@
 .me-highlights-list { padding-left: 0; padding-right: 0; }
 .explore-header .author-card { max-width: 600px; margin: 0 auto; width: 100%; }
 
+/* Hide tab labels on mobile to save space */
+@media (max-width: 768px) {
+  .me-tab .tab-label {
+    display: none;
+  }
+  
+  .me-tab {
+    padding: 0.75rem;
+    gap: 0;
+  }
+}
+
 /* Bookmarks list */
 .bookmarks-list {
   display: flex;