chore: add banner

Author: ldez

docs/assets/css/custom.css

@@ -40,3 +40,13 @@
 .hextra-footer .social-media :hover{
     transform: translateY(-2px);
 }
+
+.hextra-banner {
+    background: #6BB43A;
+    background: linear-gradient(135deg, rgba(107, 180, 58, 1) 0%, rgba(29, 253, 253, 1) 50%, rgba(69, 145, 252, 1) 100%);
+    color: var(--hx-color-slate-900);
+}
+
+.extra-banner-close-button {
+    color: var(--hx-color-slate-50);
+}

docs/hugo.yaml

@@ -82,6 +82,11 @@ menu:
 params:
   description: Golangci-lint is a fast linters runner for Go.
 
+  banner:
+    key: 'announcement-v2_4'
+    message: |
+      New golangci-lint release ([v2.4](/docs/product/changelog/)) with support of Go 1.25 🎉🎉🎉 It's time to [support us](/docs/donate/) to keep golangci-lint always up to date! 
+
   navbar:
     displayTitle: true
     displayLogo: true