var view;
function initResizeMob() {
  view = document.getElementById("bg");
  if(view) {
    view.pr = view.getAttribute('width')/view.getAttribute('height');
    initBgMob();
  }
  
}
function initBgMob(){
  var w = document.documentElement.offsetWidth;
  var h = document.documentElement.offsetHeight;
  var spr = w/h;
  if(spr > view.pr) {
    view.style.width = w + "px";
    view.style.height = w/view.pr + "px";
    view.style.left = 0 + "px";
    view.style.top = h/2 - w/view.pr/2 + "px";
  }else{
    view.style.height = h + "px";
    view.style.width = h*view.pr + "px";
    view.style.top = 0 + "px";
    view.style.left = w/2 - h*view.pr/2 + "px";
  }
}

var mobi = ['opera', 'iemobile', 'webos', 'android', 'ipad', 'safari'];
var midp = ['blackberry', 'symbian'];
var ua = navigator.userAgent.toLowerCase();

if ((ua.indexOf('midp') != -1) || (ua.indexOf('mobi') != -1) || ((ua.indexOf('ppc') != -1) && (ua.indexOf('mac') == -1)) || (ua.indexOf('webos') != -1)) {
   if (window.addEventListener) {window.addEventListener("load", initResizeMob, false);}
  else if (window.attachEvent) {window.attachEvent("onload", initResizeMob);}
  if (window.addEventListener) {window.addEventListener("resize", initBgMob, false);}
  else if (window.attachEvent) {window.attachEvent("onresize", initBgMob);}
  if (window.addEventListener) {window.addEventListener("scroll", initResizeMob, false);}
  else if (window.attachEvent) {window.attachEvent("onscroll", initResizeMob);}
}
else {
  if (window.addEventListener) {window.addEventListener("load", initResize, false);}
  else if (window.attachEvent) {window.attachEvent("onload", initResize);}
  if (window.addEventListener) {window.addEventListener("resize", initBg, false);}
  else if (window.attachEvent) {window.attachEvent("onresize", initBg);}
  if (window.addEventListener) {window.addEventListener("scroll", initResize, false);}
  else if (window.attachEvent) {window.attachEvent("onscroll", initResize);}
}

var _width,  _height;
function initResize() {
  view = document.getElementById("bg");
  if (view) {
    _width = view.getAttribute('width');
    _height = view.getAttribute('height');
    view.pr = _width/_height;
    initBg();
  }
}
function initBg(){
  var w = document.documentElement.offsetWidth;
  var h = document.documentElement.offsetHeight;
  if(w > _width || h > _height){
  
    var spr = w/h;
    if(spr > view.pr) {
      view.style.width = w + "px";
      //view.style.height = w/view.pr + "px";
      view.style.left = getScrollX() + "px";
      //view.style.top = h/2 - w/view.pr/2 + "px";
    }else{
      //view.style.height = h + "px";
      view.style.width = h*view.pr + "px";
      //view.style.top = 0 + "px";
      view.style.left = w/2 - h*view.pr/2 + "px";
    }
    view.style.top = "137px";
    if (view.getAttribute('width') > w){view.style.left = getScrollX() + "px";}
    
  }
  function getScrollX (){
    if ((navigator.appName.indexOf('Microsoft Internet Explorer') != -1) && (parseInt(navigator.appVersion) < 8)){
      return document.documentElement.scrollLeft;
    }else{return 0;}
  }
}