always show scroll bar for a scrollable table using css code example

Example 1: style scrollbar table

table::-webkit-scrollbar{
    /*Your styles here*/
}
table::-webkit-scrollbar-thumb{
    /*Your styles here*/
}
table::-webkit-scrollbar-thumb:window-inactive{
    /*Your styles here*/
}

Example 2: div scrollable

<div id="" style="overflow:scroll; height:400px;">