se arreglo que no aceptaba el 2

WebContent/cartas.html

@@ -51,7 +51,7 @@
 
 
       <div class="form-group">
       <div class="form-group">
         <label for="tarea">Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K</label>
         <label for="tarea">Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K</label>
-        <input type="text" class="form-control" required pattern="A|a|A|A|3|4|5|6|7|8|9|T|t|j|J|q|Q|K|k" title="Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K" id="valor" name="valor" placeholder="Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K" required  maxlength="1" >
+        <input type="text" class="form-control" required pattern="A|a|2|3|4|5|6|7|8|9|T|t|j|J|q|Q|K|k" title="Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K" id="valor" name="valor" placeholder="Valores posibles: A,2,3,4,5,6,7,8,9,T,J,Q,K" required  maxlength="1" >
       </div>
       </div>
 
 
       <div class="d-flex">
       <div class="d-flex">