diff --git a/frontend/src/styles/app.css b/frontend/src/styles/app.css
index 31712b8..206a5b5 100644
--- a/frontend/src/styles/app.css
+++ b/frontend/src/styles/app.css
@@ -49,3 +49,15 @@
   ul, ol, figure, details, summary { padding: 0; margin: 0; }
   h1, h2, h3, h4, h5, h6, p { margin: 0; }
 }
+
+/* Active-tab indicator (operator-flagged 2026-07-13 in the Vuetify-4 review): v4's
+   MD3 v-tab "slider" underline renders wider than the tab and floats below it. The
+   active tab's TEXT is already accent-coloured (color="accent"), so drop the slider
+   and mark the active tab with a subtle accent fill + rounded top — a clean,
+   unambiguous highlight app-wide (Subscriptions / Browse / Settings / Series). */
+.v-tab__slider { display: none !important; }
+.v-tab[aria-selected="true"],
+.v-tab.v-tab--selected {
+  background: rgb(var(--v-theme-accent) / 0.12);
+  border-radius: 8px 8px 0 0;
+}