.fixed{
  height: 100%;
  overflow: hidden;
}

div.overlay {
	position: fixed;
	z-index: 1;
	background: rgba(0,0,0,.6);
	width: 100%;
	height: 100%;
	overflow: hidden;
}

.modal {
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  background: none;
  padding: 10px;
  overflow: auto;
  z-index: 1001;
  position: fixed;
  width: 640px;
  min-height: 360px;
  max-height: 600px;
  line-height:1.4;
}
#popup {
  background: url(../img/popupbg.png) no-repeat;
  width: 629px;
  height: 470px;
}
#popup #p_btn {
  position: absolute;
  bottom: 160px;
  left: 128px;
  cursor: pointer;
}
@media screen and (max-width: 768px){
  #popup {
    background: url(../img/popupbg_sp.png) no-repeat;
    background-size: 250px auto;
    height: 285px;
    width: 250px;
  }
  #popup #p_btn {
    bottom: 200px;
    left: 30px;
    right: 30px;
  }
}