diff --git a/backend/competition/serializers.py b/backend/competition/serializers.py
index 489b178..55f0787 100644
--- a/backend/competition/serializers.py
+++ b/backend/competition/serializers.py
@@ -13,10 +13,7 @@ class CarouselItemSerializer(serializers.ModelSerializer):
                   'order', 'is_active']
     
     def get_display_image(self, obj):
-        request = self.context.get('request')
         if obj.image:
-            if request:
-                return request.build_absolute_uri(obj.image.url)
             return obj.image.url
         return obj.image_url
 
@@ -33,10 +30,7 @@ class HomePageConfigSerializer(serializers.ModelSerializer):
                   'organizer', 'undertaker', 'carousel1_items', 'carousel2_items']
 
     def get_display_banner(self, obj):
-        request = self.context.get('request')
         if obj.banner_image:
-            if request:
-                return request.build_absolute_uri(obj.banner_image.url)
             return obj.banner_image.url
         return obj.banner_image_url
 
@@ -54,6 +48,7 @@ class ScoreDimensionSerializer(serializers.ModelSerializer):
         model = ScoreDimension
         fields = ['id', 'name', 'description', 'weight', 'max_score', 'order']
 
+
 class CompetitionSerializer(serializers.ModelSerializer):
     score_dimensions = ScoreDimensionSerializer(many=True, read_only=True)
     display_cover_image = serializers.SerializerMethodField()
@@ -67,13 +62,11 @@ class CompetitionSerializer(serializers.ModelSerializer):
                   'score_dimensions', 'created_at']
 
     def get_display_cover_image(self, obj):
-        request = self.context.get('request')
         if obj.cover_image:
-            if request:
-                return request.build_absolute_uri(obj.cover_image.url)
             return obj.cover_image.url
         return obj.cover_image_url
 
+
 class CompetitionEnrollmentSerializer(serializers.ModelSerializer):
     user = WeChatUserSerializer(read_only=True)
     
@@ -82,6 +75,7 @@ class CompetitionEnrollmentSerializer(serializers.ModelSerializer):
         fields = ['id', 'competition', 'user', 'role', 'status', 'created_at']
         read_only_fields = ['status']
 
+
 class ProjectFileSerializer(serializers.ModelSerializer):
     class Meta:
         model = ProjectFile
@@ -90,12 +84,12 @@ class ProjectFileSerializer(serializers.ModelSerializer):
     def validate_file(self, value):
         if not value:
             return value
-        # 50MB limit
         limit_mb = 50
         if value.size > limit_mb * 1024 * 1024:
             raise serializers.ValidationError(f"文件大小不能超过 {limit_mb}MB")
         return value
 
+
 class ProjectSerializer(serializers.ModelSerializer):
     files = ProjectFileSerializer(many=True, read_only=True)
     contestant_info = serializers.SerializerMethodField()
@@ -115,13 +109,11 @@ class ProjectSerializer(serializers.ModelSerializer):
         }
 
     def get_display_cover_image(self, obj):
-        request = self.context.get('request')
         if obj.cover_image:
-            if request:
-                return request.build_absolute_uri(obj.cover_image.url)
             return obj.cover_image.url
         return obj.cover_image_url
 
+
 class ScoreSerializer(serializers.ModelSerializer):
     judge_name = serializers.CharField(source='judge.user.nickname', read_only=True)
     dimension_name = serializers.CharField(source='dimension.name', read_only=True)
@@ -131,6 +123,7 @@ class ScoreSerializer(serializers.ModelSerializer):
         fields = ['id', 'project', 'judge', 'dimension', 'score', 'judge_name', 'dimension_name', 'created_at']
         read_only_fields = ['judge']
 
+
 class CommentSerializer(serializers.ModelSerializer):
     judge_name = serializers.CharField(source='judge.user.nickname', read_only=True)
     score = serializers.SerializerMethodField()
@@ -144,15 +137,11 @@ class CommentSerializer(serializers.ModelSerializer):
         scores = Score.objects.filter(project=obj.project, judge=obj.judge)
         if not scores.exists():
             return None
-            
-        current_judge_total_score = 0
-        current_judge_total_weight = 0
-        
+        total_score = 0
+        total_weight = 0
         for score in scores:
-            current_judge_total_score += score.score * score.dimension.weight
-            current_judge_total_weight += score.dimension.weight
-        
-        if current_judge_total_weight > 0:
-            judge_score = current_judge_total_score / current_judge_total_weight
-            return round(judge_score, 1)
+            total_score += score.score * score.dimension.weight
+            total_weight += score.dimension.weight
+        if total_weight > 0:
+            return round(total_score / total_weight, 1)
         return None