.mt-popup-dialog {
  position: fixed;
  left: 0;
  bottom: 0;
  width: 100%;
  background: transparent;
  z-index: 501;
  transition-property: transform;
  transition-duration: 300ms;
  max-height: 100%;
  overflow-y: scroll;
  -webkit-overflow-scrolling: touch;
}
.mt-popup-dialog.mt-popup-left {
  width: auto;
  height: 100%;
  top: 0;
  right: auto;
  bottom: auto;
  left: 0;
}
.mt-popup-dialog.mt-popup-right {
  width: auto;
  height: 100%;
  top: 0;
  right: 0;
  bottom: auto;
  left: auto;
}
.mt-popup-dialog.mt-popup-top {
  width: 100%;
  top: 0;
  right: auto;
  bottom: auto;
  left: 0;
}
.mt-popup-mask {
  display: block;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  tap-highlight-color: rgba(0,0,0,0);
  z-index: -1;
  transition: opacity 400ms;
}
.mt-popup-mask.mt-popup-show {
  opacity: 1;
}