fix: lower actividad-card opacity to 70%

public/index.html

@@ -535,7 +535,7 @@
     }
 
     .actividad-card {
-      background: rgba(255,255,255,0.85);
+      background: rgba(255,255,255,0.70);
       border-radius: 10px;
       overflow: hidden;
       box-shadow: 0 5px 25px rgba(0,0,0,0.08);