Top panel's menu border is not visible

[ASTO]

<div class="Top_panel">
    <div  class="menu"  style="border: 10px black;">
        <h1><a href='#' target="_blank">menu</a></h1>
    </div>

https://www.hizliresim.com/k6sxxim

I want to add vertical border

 

[aCodeMonkey]

Asto,

You will need to use two CSS border styles for adding vertical borders to either side of the layer.

Use border shorthand for each side. e.g. border-left: style width color; and/or border-right: style width color;"

<div class="Top_panel">
    <div  class="menu"  style="border-left: solid 10px black; border-right: solid 10px black;">
        <h1><a href='#' target="_blank">menu</a></h1>
    </div>
</div>