How to set search input box on header frame in html

I have 03 frame (Header, Left_Menu and Content). In header frame I set a search input box. If anyone click on search input box then a blue color div show under the search input box but above content frame. But When I click search input box then blue color div box don’t show above content frame.

I want to create search input box as following example:

But my search input box result show as following example:

Please, anyone can help to solve this problem.

Nowadays <frame> is not recommended. You want to overflow your header onto the content.

This is only feasible, if you don't use frames. You should use for example a simple <div> HTML tag instead of the frames.

After that, you should add some CSS property, which results the desired effect. For example:

#header{
    position: relative;
    z-index: 2;
    heigth: 100px;
}

You should add the z-index property. You can read more about z-index here: Z-index - CSS