diff --git a/src/main/java/com/ntlab/irisserver/entities/Card.java b/src/main/java/com/ntlab/irisserver/entities/Card.java
index ebc574d..ab9160b 100644
--- a/src/main/java/com/ntlab/irisserver/entities/Card.java
+++ b/src/main/java/com/ntlab/irisserver/entities/Card.java
@@ -5,13 +5,13 @@
 public class Card {
 
     @JsonProperty("isOpen")
-    public boolean isOpen;
+    private boolean isOpen;
 
     @JsonProperty("color")
-    public String color;
+    private String color;
 
     @JsonProperty("dno")
-    public int dno;
+    private int dno;
 
     public void setIsOpen(boolean isOpen) {this.isOpen = isOpen;}