Want to change color just below Second level navigation Tab (part of Menu bar color)

Hi All,

Portal version: SAP 7.4

Theme used : Tradeshow

Page: Ajax Framework page

I have changed the Menu bar colour, due to which a line is coming after second level navigation with same color. Please sugget how to change the color of this line, or remove this line.

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Thanks and Regards,

Khushboo Agarwal