bootstrap removal phase 2: badge/alert/pagination -> custom CSS

Replaced three more Bootstrap partials with ~40 lines of custom CSS and dropped
their imports:
- badge: matches former output exactly (last.fm + analytics counts).
- alert: contact-form messages; added real green/red (BS color variants no
  longer compiled since theme-colors was trimmed).
- pagination: flex container only (WP paginate_links emits .page-numbers,
  already styled in style.css).
v4-style.min.css 199,448 -> 194,480 bytes (-15.5 KB total across phases 1-2).

css/styles.scss

@@ -77,19 +77,63 @@ $enable-negative-margins: true;
 @import '../node_modules/bootstrap/scss/nav';
 @import '../node_modules/bootstrap/scss/navbar';
 @import '../node_modules/bootstrap/scss/card';
-@import '../node_modules/bootstrap/scss/pagination';
-@import '../node_modules/bootstrap/scss/alert';
 @import '../node_modules/bootstrap/scss/list-group';
-@import '../node_modules/bootstrap/scss/badge';
 @import '../node_modules/bootstrap/scss/helpers';
 @import '../node_modules/bootstrap/scss/utilities/api';
 
-// Replaces the dropped bootstrap/images partial (only .img-fluid was used).
+// ---- replacements for dropped Bootstrap partials (Phase 1 + 2) ----
+
+// images partial: only .img-fluid was used (art page).
 .img-fluid {
   max-width: 100%;
   height: auto;
 }
 
+// badge: last.fm stat counts (music) + analytics hit counts. Matches the
+// former bootstrap/badge output exactly (incl. the theme's top:-1px nudge).
+.badge {
+  display: inline-block;
+  padding: 0.35em 0.65em;
+  font-size: 0.75em;
+  font-weight: 700;
+  line-height: 1;
+  color: #fff;
+  text-align: center;
+  white-space: nowrap;
+  vertical-align: baseline;
+  border-radius: 0.375rem;
+  position: relative;
+  top: -1px;
+}
+
+// alert: contact-form success / error messages (inc/tweaks.php). The BS
+// colour variants no longer compiled (theme-colors trimmed) — give them
+// real green/red here.
+.alert {
+  position: relative;
+  padding: 1rem;
+  margin-bottom: 1rem;
+  border: 1px solid transparent;
+  border-radius: 0.375rem;
+}
+.alert-success {
+  color: #0a3622;
+  background-color: #d1e7dd;
+  border-color: #a3cfbb;
+}
+.alert-danger {
+  color: #58151c;
+  background-color: #f8d7da;
+  border-color: #f1aeb5;
+}
+
+// pagination: flex container only. WP paginate_links() emits .page-numbers /
+// .pagination a, styled in style.css; margin/padding also live there.
+.pagination {
+  display: flex;
+  list-style: none;
+}
+
 /* Bootstrap Icons font dropped (2026-06-19): the header's 8 nav icons are now
    inline SVG in parts/header.html, so the full icon font + its ~2000 CSS rules
    are no longer imported. */