function cover_click()
{
    selectbox_visible();
    hide_cover();
}


// 감추어진 셀렉트 박스를 모두 보이게 함
function selectbox_visible()
{
    for (i=0; i<document.forms.length; i++)
    {
        for (k=0; k<document.forms[i].length; k++)
        {
            el = document.forms[i].elements[k];
            if (el.type == "select-one" && el.disabled==true) el.disabled=false;
        }
    }
}

// 셀렉트 박스를 모두 보이게 함
function selectbox_disable()
{
    for (i=0; i<document.forms.length; i++)
    {
        for (k=0; k<document.forms[i].length; k++)
        {
            el = document.forms[i].elements[k];
            if (el.type == "select-one" && el.disabled==false) {
                el.disabled=true;
            }
        }
    }
}

// IE 레이어에서 셀렉트 박스 보이는 문제
function selectbox_hidden(layer_id)
{
    var ly = eval(layer_id);

    // 레이어 좌표
    var ly_left = ly.offsetLeft;
    var ly_top = ly.offsetTop;
    var ly_right = ly.offsetLeft + ly.offsetWidth;
    var ly_bottom = ly.offsetTop + ly.offsetHeight;

    // 셀렉트박스의 좌표
    var el;

    for (i=0; i<document.forms.length; i++)
    {
        for (k=0; k<document.forms[i].length; k++)
    {
            el = document.forms[i].elements[k];
            if (el.type == "select-one")
        {
                var el_left = el_top = 0;
                var obj = el;
                if (obj.offsetParent)
        {
                    while (obj.offsetParent)
            {
                        el_left += obj.offsetLeft;
                        el_top += obj.offsetTop;
                        obj = obj.offsetParent;
                    }
                }
                el_left += el.clientLeft;
                el_top += el.clientTop;
                el_right = el_left + el.clientWidth;
                el_bottom = el_top + el.clientHeight;

               // 좌표를 따져 레이어가 셀렉트 박스를 침범했으면 셀렉트 박스를 hidden 시킴
               if ( (el_left >= ly_left && el_top >= ly_top && el_left <= ly_right && el_top <= ly_bottom) || (el_right >= ly_left && el_right <= ly_right && el_top >= ly_top && el_top <= ly_bottom) || (el_left >= ly_left && el_bottom >= ly_top && el_right <= ly_right && el_bottom <= ly_bottom) || (el_left >= ly_left && el_left <= ly_right && el_bottom >= ly_top && el_bottom <= ly_bottom) )
               el.disabled=true;
           }
       }
    }
}
function show_cover()
{
    var obj = document.getElementById("link_screen_cover");
    obj.style.height = document.body.scrollHeight;
    obj.style.display = "";
}

function hide_cover()
{
    var obj = document.getElementById("link_screen_cover");
    obj.style.display = "none";
}