<html>

<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  <link rel="stylesheet" type="text/css" />
  <title>Демонстрация.</title>
  <style>
    #slider {
      width: 100%;
      color: #66666;
      font-family: Georgia;
      font-size: 20px;
    }
    
    .header {
      width: 23%;
      display: inline-block;
      border: 1px solid #cccccc;
      padding: 8px;
      margin-top: 5px;
      cursor: pointer;
      text-align: center;
    }
    
    .header:hover {
      color: #666666;
    }
    
    .content {
      overflow: hidden;
      position: absolute;
      width: 100%;
      margin-top: 5px;
    }
    
    .text {
      width: 100%;
      border: 1px solid #cccccc;
      border-top: none;
      padding: 15px;
      text-align: left;
      background: #eeeeee;
      font-size: 14px;
    }
    
    .regtangle {
      position: absolute;
      width: 23%;
      margin-top: 13px;
      z-index: 999;
    }
    
    .regtangle:after {
      width: 40px;
      height: 20px;
      content: url("http://berloga-guns.com/assets/templates/berloga/img/regtangle.png");
    }
  </style>
  <script src="https://code.jquery.com/jquery-3.1.0.min.js"></script>

  <script type="text/javascript">
    var array = new Array();
    var speed = 10;
    var timer = 10;
    var arrhe = new Array();

    
    function slider(target, showfirst) {
      var slider = document.getElementById(target);
      var divs = slider.getElementsByTagName('div');
      var divslength = divs.length;
      for (i = 0; i < divslength; i++) {
        var div = divs[i];
        var divid = div.id;
        if (divid.indexOf("header") != -1) {
          div.onclick = new Function("processClick(this)");
        } else if (divid.indexOf("content") != -1) {
          var section = divid.replace('-content', '');
          array.push(section);
          div.maxh = div.offsetHeight;
          if (showfirst == 1 && i == 1) {
            //speed = 10;
            div.style.display = 'block';
          } else {
            //speed = 0;
            div.style.display = 'none';
          }
        }
      }
    }


    function processClick(div) {

      sourc = document.getElementsByClassName("header");
      var figure = document.createElement('div');
      figure.className = "regtangle";

      for (i = 0; i < sourc.length; i++) {
        sourc[i].style.margin = '5px 0 0 0';
      }

      var catlength = array.length;
      for (i = 0; i < catlength; i++) {
        var section = array[i];
        var head = document.getElementById(section + '-header');
        var cont = section + '-content';
        var contdiv = document.getElementById(cont);
        clearInterval(contdiv.timer);
        if (head == div && contdiv.style.display == 'none') {

          var iiigh = '#' + cont;
          var h = $('#' + cont + '').height();

          if (h != 0) {
            arrhe[i] = h;
            head.appendChild(figure);
            figure.style.display = 'block';
          } else {
            h = arrhe[i];
          }

          h4 = parseInt(h);
          var h2 = h4 + 5;


          head.style.margin = '0 0 ' + h2 + 'px 0';
          contdiv.style.display = 'block';
          contdiv.style.margin = '-' + h + 'px 0 0 0';
          initSlide(cont, 1);
        } else if (contdiv.style.display == 'block') {
          initSlide(cont, -1);
        }
      }
    }

    function initSlide(id, dir) {
      var cont = document.getElementById(id);
      var maxh = cont.maxh;
      cont.direction = dir;
      cont.timer = setInterval("slide('" + id + "')", timer);
    }

    function slide(id) {
      var cont = document.getElementById(id);
      var maxh = cont.maxh;
      var currheight = cont.offsetHeight;
      var dist;

      if (cont.direction == 1) {
        dist = (Math.round((maxh - currheight) / speed));
      } else {
        dist = (Math.round(currheight / speed));
      }
      if (dist <= 1) {
        dist = 1;
      }
      cont.style.height = currheight + (dist * cont.direction) + 'px';
      cont.style.opacity = currheight / cont.maxh;
      cont.style.filter = 'alpha(opacity=' + (currheight * 100 / cont.maxh) + ')';
      if (currheight < 2 && cont.direction != 1) {
        cont.style.display = 'none';
        clearInterval(cont.timer);
      } else if (currheight > (maxh - 2) && cont.direction == 1) {
        clearInterval(cont.timer);
      }
    }
  </script>
</head>

<body onload="slider('slider',0)">

  <div id="slider">
    <div class="header" id="29-header">Первый блок</div>
    <div class="content" id="29-content">
      <div class="text">
        Содержимое блока 1
      </div>
    </div>
    <div class="header" id="2-header">Второй блок</div>
    <div class="content" id="2-content">
      <div class="text">
        Содержимое блока 2
      </div>
    </div>
    <div class="header" id="3-header">Третий блок</div>
    <div class="content" id="3-content">
      <div class="text">
        Содержимое блока 3
      </div>
    </div>
    <div class="header" id="4-header">Четвертый</div>
    <div class="content" id="4-content">
      <div class="text">
        Содержимое блока 4
      </div>
    </div>

    <div class="header" id="5-header">Пятый</div>
    <div class="content" id="5-content">
      <div class="text">
        Содержимое блока 5
      </div>
    </div>
    <div class="header" id="6-header">Шестой</div>
    <div class="content" id="6-content">
      <div class="text">
        Содержимое блока 6
      </div>
    </div>
    <div class="header" id="7-header">Седьмой</div>
    <div class="content" id="7-content">
      <div class="text">
        Содержимое блока 7
      </div>
    </div>
    <div class="header" id="8-header">Восьмой</div>
    <div class="content" id="8-content">
      <div class="text">
        Содержимое блока 8
      </div>
    </div>

    <div class="header" id="9-header">Девятый</div>
    <div class="content" id="9-content">
      <div class="text">
        Содержимое блока 9
      </div>
    </div>
    <div class="header" id="10-header">Десятый</div>
    <div class="content" id="10-content">
      <div class="text">
        Содержимое блока 10
      </div>
    </div>

  </div>


</body>

</html>