In ASPX page, I add CSS as below.

Both vertical and horizontal scroll bars display but grey out.

How to make scroll bars showing and working?

.mybody {
margin: 0;
background: url("images/backgroundjob.png");
background-size: 4000px 250px;
background-repeat: no-repeat;

overflow: scroll;
}

<body class="mybody">

---some div, panel here

</body>