@media only screen and (max-width: 640px){

a#menu{
  display: inline-block;
  position: relative;
  width: 40px;
  height: 40px;
  margin: 10px;
}

#menuBtn{
  display: block;
  position: absolute;
  top: 50%;
  left: 50%;
  width: 18px;
  height: 2px;
  margin: -1px 0 0 -7px;
  background: #fff;
  transition: .2s;
}

#menuBtn:before, #menuBtn:after{
  display: block;
  content: "";
  position: absolute;
  top: 50%;
  left: 0;
  width: 18px;
  height: 2px;
  background: #fff;
  transition: .3s;
}

#menuBtn:before{
  margin-top: -7px;
}

#menuBtn:after{
  margin-top: 5px;
}

a#menu .close{
  background: transparent;
}

a#menu .close:before, a#menu .close:after{
  margin-top: 0;
}

a#menu .close:before{
  transform: rotate(-45deg);
  -webkit-transform: rotate(-45deg);
}

a#menu .close:after{
  transform: rotate(-135deg);
  -webkit-transform: rotate(-135deg);
}

.panel{
  width: 100%;
  display: none;
  overflow: hidden;
  position: relative;
  left: 0;
  top: 0;
  z-index: 100;
}

#mainnav{
  position:fixed;
  top: 0;
  width:100%;
  z-index:900;
}

#mainnav ul{
  text-align: right;
  padding-right: 30px;
}

#mainnav li{
  display: inline-block;
  padding: 45px 10px 20px;
  font-size: 14px;
  font-weight: 300;
}

#mainnav a{
  color: #f39801;
}

#mainnav.changeNav{
  background: rgba(255,255,255,.9);
  border-bottom: 1px solid #d1d1d1;
}

#mainnav.changeNav li{
  padding: 20px 10px;
}

}