diff --git a/common/constants.go b/common/constants.go
index 70589041..a9f8a2d5 100644
--- a/common/constants.go
+++ b/common/constants.go
@@ -100,7 +100,11 @@ var RelayTimeout = GetOrDefault("RELAY_TIMEOUT", 0) // unit is second
 
 var GeminiSafetySetting = GetOrDefaultString("GEMINI_SAFETY_SETTING", "BLOCK_NONE")
 
-var Theme = GetOrDefaultString("THEME", "default")
+var Theme = "default"
+var ValidThemes = map[string]bool{
+	"default": true,
+	"berry":   true,
+}
 
 const (
 	RequestIdKey = "X-Oneapi-Request-Id"
diff --git a/controller/option.go b/controller/option.go
index bbf83578..3b1cbad2 100644
--- a/controller/option.go
+++ b/controller/option.go
@@ -42,6 +42,14 @@ func UpdateOption(c *gin.Context) {
 		return
 	}
 	switch option.Key {
+	case "Theme":
+		if !common.ValidThemes[option.Value] {
+			c.JSON(http.StatusOK, gin.H{
+				"success": false,
+				"message": "无效的主题",
+			})
+			return
+		}
 	case "GitHubOAuthEnabled":
 		if option.Value == "true" && common.GitHubClientId == "" {
 			c.JSON(http.StatusOK, gin.H{