.mb10 {
  margin-bottom: 10px !important; }

.mb15 {
  margin-bottom: 15px !important; }

.mb20 {
  margin-bottom: 20px !important; }

.mb25 {
  margin-bottom: 25px !important; }

.mb30 {
  margin-bottom: 30px !important; }

.mb35 {
  margin-bottom: 35px !important; }

.mb40 {
  margin-bottom: 40px !important; }

.mb45 {
  margin-bottom: 45px !important; }

.mb50 {
  margin-bottom: 50px !important; }

/* スクロールバーは常に表示 */
html {
  overflow-y: scroll;
}

#content {
  width: 100%;
  min-width: 980px;
  padding-top: 100px;
  position: relative;
  left: 0px;
  top: 0px;
  z-index: 0; }

#front {
  width: 100%;
  position: relative;
  z-index: 1;
  overflow: hidden;
  display: flex;
  justify-content: center;

}

#front #title {
  margin-left: -209px;
  margin-top: 14px;
  position: fixed;
  left: 50%;
  top: 50%;
  z-index: 1;
}
#front #scrollIcon {
  margin-left: -49px;
  margin-top: 110px;
  position: fixed;
  left: 50%;
  top: 50%;
  z-index: 1;
}

#front #message {
  /*
  display: none;
  opacity: 0;
  position: fixed;
  left: 50%;
  transform: translateX(-50%);
  bottom: 0px;
  */
  position: absolute;
}
@media all and (-ms-high-contrast:none){
  *::-ms-backdrop, #front #message {
    left: 18%;/* IE11対応 */
  }
}

#front #message-last {
  margin-left: -154px;
  margin-top: -15px;
  position: fixed;
  left: 50%;
  top: 50%;
  z-index: 9; }

#front #backbtn {
  /*
  margin-left: -50px;
  margin-top: -10px;
  padding-bottom: 3px;
  */
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%,-50%);
  z-index: 10;
  color: white;
  font-size: 20px;
  font-size: 1.25rem;
  font-family: serif;
  cursor: pointer;
}

#bg {
  width: 100%;
  position: fixed;
  left: 0px;
  top: 100px;
  z-index: 0;
  overflow: hidden; }

#bg img {
  position: absolute;
  left: 0px;
  top: 0px;
  z-index: 0; }

#bg #bg1 {
  z-index: 4; }

#bg #bg2 {
  z-index: 3; }

#bg #bg3 {
  z-index: 2; }

#bg #bg4 {
  z-index: 1; }

/* ScrollAnimation
------------------------------ */
/* Message */
#front #message img {
  opacity: 0;
  pointer-events: none;
  transition: opacity 1s 0.5s ease;
}
#front.is-active #message img {
  opacity: 1;
  pointer-events: auto;
}
/* Title, scrollIcon */
#front #title,
#front #scrollIcon {
  opacity: 1;
  pointer-events: auto;
  transition: opacity 1s ease;
}
#front.is-active #title,
#front.is-active #scrollIcon {
  opacity: 0;
  pointer-events: none;
}

/* message-last, scrollIcon */
#front #message-last,
#front #backbtn {
  opacity: 0;
  pointer-events: none;
}
#front #message-last {

}
#front.is-end #message-last {
  animation: fade-inout 2s ease;
}
#front #backbtn {
  transition: opacity 1s ease;
}
#front.is-end #backbtn.is-active {
  opacity: 1;
  pointer-events: auto;
}

#bg #bg1 {
  transition: opacity .8s linear;
}
#bg #bg2 {
  transition: opacity .8s 1.6s linear;
}
#bg #bg3 {
  transition: opacity .8s 2.4s linear;
}
#bg.is-active #bg1, #bg.is-active #bg2, #bg.is-active #bg3 {
  opacity: 0;
}


@keyframes fade-inout {
  0 {
    opacity: 0;
  }
  20% {
    opacity: 1;
  }
  50% {
    opacity: 1;
  }
  80% {
    opacity: 1;
  }
  100% {
    opacity: 0;
  }
}