diff --git a/file-upload-site/app.py b/file-upload-site/app.py
index 53db67c..1350a28 100644
--- a/file-upload-site/app.py
+++ b/file-upload-site/app.py
@@ -90,7 +90,7 @@ def generate_captcha_text(length: int = 4) -> str:
 
 def generate_captcha_image(text: str) -> Image.Image:
     """生成验证码图片（含干扰线和噪点）"""
-    width, height = 220, 70
+    width, height = 320, 100
     # 浅色随机背景
     bg_color = (random.randint(235, 255), random.randint(235, 255), random.randint(235, 255))
     image = Image.new('RGB', (width, height), bg_color)
@@ -111,13 +111,13 @@ def generate_captcha_image(text: str) -> Image.Image:
 
     # 绘制文字
     try:
-        font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", 50)
+        font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", 65)
     except OSError:
         font = ImageFont.load_default()
 
     for i, char in enumerate(text):
-        x = 16 + i * 50
-        y = random.randint(4, 12)
+        x = 20 + i * 72
+        y = random.randint(6, 18)
         color = (random.randint(0, 80), random.randint(0, 80), random.randint(0, 80))
         draw.text((x, y), char, font=font, fill=color)
 
diff --git a/file-upload-site/style.css b/file-upload-site/style.css
index bf93bff..5b87e4e 100644
--- a/file-upload-site/style.css
+++ b/file-upload-site/style.css
@@ -610,8 +610,9 @@ input[type="text"].input-error {
 }
 
 .modal-captcha-img {
-    height: 70px;
-    flex: 1;
+    height: 80px;
+    width: 240px;
+    flex: none;
     border-radius: var(--radius-sm);
     border: 1.5px solid var(--border);
     cursor: pointer;