Removing the border radius from the Tweet timeline



We have embedded the Tweet timeline in our new website under development and noticed that div.timeline has border-radius set to 5px. We would like to set the border-radius of div.timeline to 0 so that the corners of the Tweet timeline are all right angles. However, even though we included the following code in the linked CSS file, the border radius remains as 5px:

.timeline{border-radius:0 !important}

We are aware of the Chrome settings from,
but none of these settings can change the border-radius property of the widget.

Please advise us how the border radius could be set to 0.

Thank you in advance,