JSFiddle - React, Tailwind, and code Playground

HTML

<!Doctype html>
<html>
<body>
<div id="container">
    <div id="header">
        <div style="font:13px/27px Arial,sans-serif; height:30px;">
            <div style="left:0; padding-left:4px;">
                <ol id="menu">
                    <li class="menu">
                        <span name="menu_top" class="top"></span>
                        <span name="menu_name" class="menu">
                            <a class="menu" href="/monitor/monitor.php" style="" data-menu2="monitor"><span>Monitor</span></a><a class="menu2" href="">
                                <span class="menu2"></span>
                            </a>
                        </span>
                    <li class="menu">
                        <span name="menu_top" class="top"></span>
                        <span name="menu_name" class="menu">
                            <a href="/php/ticket/ajax/" class="menu" data-menu2="ticket"><span>Ticket</span></a>
                            <a href="" class="menu2">
                                <span class="menu2"></span>
                            </a>
                        </span>
                    </li>

                    <li class="menu">
                        <span name="menu_top" class="top"></span>
                        <span name="menu_name" class="menu">
                            <a href="/php/quicksearch/" class="menu" data-menu2="cautare"><span>Search</span></a>
                            <a href="" class="menu2">
                                <span class="menu2"></span>
                            </a>
                        </span>
                    </li>
                 </ol>
            </div>
        </div>
    </div>
</div>
                    </body></html>

CSS

a
        {
            outline: 0;
        }

        html, body
        {
            height:100%;
            margin: 0;
            padding: 0;
            overflow: hidden;
        }

        div#content
        {
            height: 100%;
        }

        div#header, div#inner_header
        {
            -moz-box-shadow: 0px 3px 5px rgba(0,0,0,0.25); /*#858585*/
            background: none repeat scroll 0 0 transparent;
            border-bottom:1px solid #C9D7F1;
            margin-bottom:2px;
            min-width:100%;
            height:30px;
            font:13px/27px Arial,sans-serif;
            position:relative;
            z-index:1;
        }

        div#container
        {
            height:100%;
        }

        div#scrollable_content
        {
            position: absolute;
            top: 32px;
        /*    margin-top: 10px;     */
            bottom: 0px;
            overflow-y:auto;
            width: 100%;
        }



        ol#menu
        {
            display:block;
            list-style:none outside none;
            margin:0;
            padding:0;
        }

        ol#menu > li.menu
        {
            display:inline-block;
            line-height:27px;
            padding:0;
            position:relative;
            vertical-align:top;
        }

        ol#menu > li.menu > span.top
        {
            border-top: 2px solid transparent;
            display: block;
        }

        ol#menu > li.menu > span.top_selected
        {
            border-top-color: #1A54E1 !important;
            display: block;
        }

        ol#menu > li.menu > span.menu
        {
            color: #3366CC !important;
            padding: 0 1px;
            background-color:white;
            border-left: 1px solid transparent;
            display: block;
            position: relative;
            z-index: 2;
        }

        ol#menu > li.menu > span.menu_selected
        {
            color: #BCBCBC !important;
        }

  ...