fix: keep admin theme contrast consistent

backend/common/test_frontend_assets.py

@@ -20,3 +20,17 @@ def test_app_css_答题提交按钮可见且长弹窗可滚动():
     assert "background: var(--green); color: white; text-align: center" in source
     assert "max-height: calc(100dvh - 30px)" in source
     assert "overflow-y: auto" in source
+
+
+def test_admin_css_深色系统下仍保持完整浅色主题():
+    source = (STATIC_ROOT / "admin" / "css" / "hulumath_admin.css").read_text(
+        encoding="utf-8"
+    )
+
+    assert "color-scheme: light" in source
+    assert "--body-fg: #17211b" in source
+    assert "--body-bg: #f3f1e9" in source
+    assert "--darkened-bg: #ebeae3" in source
+    assert "background-color: #ffffff !important" in source
+    assert ".theme-toggle" in source
+    assert "display: none" in source