Invert Ko-fi hover: dim by default, full brightness on hover

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: asimone

index.html

@@ -312,9 +312,10 @@
   background: var(--bg);
   text-decoration: none;
   white-space: nowrap;
+  opacity: .7;
   transition: opacity .15s;
 }
-.kofi-btn:hover { opacity: .85; }
+.kofi-btn:hover { opacity: 1; }
 .footer-sep {
   color: var(--border);
   user-select: none;