fix DArrowRectangle background color abnormality

[kegechen]

FIX https://github.com/linuxdeepin/developer-center/issues/5187 Bug: https://pms.uniontech.com/bug-view-211649.html

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: kegechen

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[deepin-bot[bot]]

Doc Check bot :green_circle: Document Coverage Check Passed!

[kegechen]

暂时关闭。