diff --git a/services/screenshots.py b/services/screenshots.py
index 6923ab7..b1cd7d0 100644
--- a/services/screenshots.py
+++ b/services/screenshots.py
@@ -39,6 +39,36 @@ def _resolve_wkhtmltoimage_path() -> str | None:
     return os.environ.get("WKHTMLTOIMAGE_PATH") or shutil.which("wkhtmltoimage")
 
 
+def _read_cookie_pairs(cookies_path: str) -> list[tuple[str, str]]:
+    if not cookies_path or not os.path.exists(cookies_path):
+        return []
+    pairs = []
+    try:
+        with open(cookies_path, "r", encoding="utf-8", errors="ignore") as f:
+            for line in f:
+                line = line.strip()
+                if not line or line.startswith("#"):
+                    continue
+                parts = line.split("\t")
+                if len(parts) < 7:
+                    continue
+                name = parts[5].strip()
+                value = parts[6].strip()
+                if name:
+                    pairs.append((name, value))
+    except Exception:
+        return []
+    return pairs
+
+
+def _select_cookie_pairs(pairs: list[tuple[str, str]]) -> list[tuple[str, str]]:
+    preferred_names = {"ASP.NET_SessionId", ".ASPXAUTH"}
+    preferred = [(name, value) for name, value in pairs if name in preferred_names and value]
+    if preferred:
+        return preferred
+    return [(name, value) for name, value in pairs if name and value and name.isascii() and value.isascii()]
+
+
 def _ensure_login_cookies(account, proxy_config, log_callback) -> bool:
     """确保有可用的登录 cookies（通过 API 登录刷新）"""
     try:
@@ -89,7 +119,12 @@ def take_screenshot_wkhtmltoimage(
         cmd.extend(["--quality", str(_WKHTMLTOIMAGE_QUALITY)])
 
     if cookies_path:
-        cmd.extend(["--cookie-jar", cookies_path])
+        cookie_pairs = _select_cookie_pairs(_read_cookie_pairs(cookies_path))
+        if cookie_pairs:
+            for name, value in cookie_pairs:
+                cmd.extend(["--cookie", name, value])
+        else:
+            cmd.extend(["--cookie-jar", cookies_path])
 
     if proxy_server:
         cmd.extend(["--proxy", proxy_server])