Can not apply CSS style to border

[Vladislav Grin]

Hello!
I have added Deck of Cards to my page and CSS stylesheet.
In CSS stylesheet I wrote next code to visually hide the top border of Deck of Cards.

.aui-tabs.horizontal-tabs>.tabs-menu~.deck-cards {
 border-top: 1px solid #FFFFFF !important;
}

When I try to see "preview" of the page Confluence shows me Deck of Card without of border, but after I press save porder appears on the page.
You can find screens of trouble below.

Help me please to solve this trouble.

Thank you in advance!

[Vladislav Grin]

Hi once more.

My trouble is solved, I have found a solution.

Unfortunately Confluence change ">" sign into "&gt". To solve such things I replaced ">" with " :nth-child(n)" and it works well. 

Hope it would be helpful for some one.