feat: badge CSS with light/dark mode, custom properties, and FOUC prevention

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

content/styles/badges.css

@@ -0,0 +1,55 @@
+/* --- FOUC prevention: hide original elements immediately --- */
+.thing.link .tagline .subreddit,
+.thing.link .flat-list .comments {
+  display: none !important;
+}
+
+/* --- Badge container --- */
+.reddit-tweaks-badges {
+  margin-bottom: 4px;
+  line-height: 1.6;
+}
+
+/* --- Shared badge styles --- */
+.rt-badge {
+  display: inline-block;
+  border: 1px solid;
+  border-radius: 3px;
+  padding: 2px 6px;
+  font-size: 11px;
+  font-weight: bold;
+  text-decoration: none;
+  vertical-align: middle;
+  margin-right: 6px;
+  cursor: pointer;
+}
+
+.rt-badge:hover {
+  opacity: 0.8;
+}
+
+/* --- Light mode (default) --- */
+.rt-badge--subreddit {
+  background: var(--rt-sub-bg, transparent);
+  border-color: var(--rt-sub-border, #c84a20);
+  color: var(--rt-sub-text, #c84a20);
+}
+
+.rt-badge--comments {
+  background: var(--rt-com-bg, #e0e0e0);
+  border-color: var(--rt-com-border, #4a4a4a);
+  color: var(--rt-com-text, #4a4a4a);
+}
+
+/* --- Dark mode --- */
+.rt-dark .rt-badge--subreddit {
+  background: var(--rt-sub-bg, transparent);
+  border-color: var(--rt-sub-border, #ff6b3d);
+  color: var(--rt-sub-text, #ff6b3d);
+}
+
+.rt-dark .rt-badge--comments {
+  background: var(--rt-com-bg, #3a3a3a);
+  border-color: var(--rt-com-border, #888888);
+  color: var(--rt-com-text, #cccccc);
+}