body, h1, h2, h3, p, ul, li {
  margin: 0;
  padding: 0;
}
ul, li {
  list-style: none;
}
.inner {
  width: 1080px;
  margin: 0 auto;
}

img {
  max-width: 100%;
  height: auto;
  vertical-align: middle;
}

a {
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

.mt20 { margin-top: 20px; }
.mt30 { margin-top: 30px; }
.mt40 { margin-top: 40px; }

html {
  font-size: 62.5%;
}

* {
  box-sizing: border-box;
}

.spDisp {
  display: none;
}
@media screen and (max-width: 768px) {
  .spDisp {
    display: block;
  }
}

body {
  font-family: 'Noto Sans JP', sans-serif;
  background: url(../img/wave.webp) no-repeat;
  background-size: 100% auto;
  background-position: center 120px;
  font-size: 1.8rem;
}
body {
  animation: fluffy 3s infinite;
}
@keyframes fluffy {
  0%, 100% {
    background-position: center 120px;
  }
  50% {
    background-position: center 150px;
  }
}

@media screen and (min-width: 1800px) {
  body {
    background-position: center 180px;
    background-size: 100% 880px;
  }
}
@media screen and (max-width: 1300px) {
  body {
    background-position: center 180px;
    background-size: 120% auto;
  }
}
@media screen and (max-width: 900px) {
  body {
    background-position: center 220px;
    background-size: 120% auto;
  }
}
@media screen and (max-width: 768px) {
  body {
    font-size: 1.3rem;
  }
}
header {
  padding-top: 30px;
  position: relative;
}
header .logo {
  position: absolute;
  top: 20px;
  left: 35px;
}
header nav ul {
  display: flex;
  justify-content: center;
  gap: 0 50px;
  font-family: "Zen Maru Gothic", 'Noto Sans JP', sans-serif;
  font-weight: 700;
}
a,
a:visited {
  color: #000;
}
header h1.ani {
  text-align: center;
  margin: 100px 0;
}

main {
  padding-top: 400px;
  text-align: center;
}

.history {
  margin: 100px 0 0 0;
  padding: 300px 0 400px 0;
  position: relative;
  color: #FFF;
  background: #202428;
}
.history::before {
  position: absolute;
  content: "";
  display: block;
  background: url(../img/wave2_top.webp) no-repeat;
  background-position: top center;
  height: 278px;
  width: 100%;
  top: 0;
  left: 0;
}
@media screen and (max-width: 768px) {
  .history::before {
    background-size: 110%;
    height: 100%;
  }
}
.history::after {
  position: absolute;
  content: "";
  display: block;
  background: url(../img/wave2_bottom.webp) no-repeat;
  background-position: bottom center;
  height: 432px;
  width: 100%;
  bottom: 0;
  left: 0;
}
.youtube iframe {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
}

.history .button {
  background: url(../img/film.webp) no-repeat;
  background-position: center center;
  background-size: auto auto;
  padding: 200px 0;
}
.history .button a {
  display: inline-block;
  padding: 15px 120px;
  background: #FFF;
  position: relative;
  border-radius: 70px;
}
.history .button a::after {
  content: "";
  width: 51px;
  height: 51px;
  background: url(../img/arrow.gif) no-repeat;
  position: absolute;
  right: 35px;
  top: 50%;
  margin-top: -25.5px;
}
.history .button a span {
  border-top: 5px dotted red;
  display: inline-block;
  font-size: 3rem;
  padding-top: 5px;
  margin-top: 10px;
}

.topics {
  background: #e5eaed;
  position: relative;
  padding-bottom: 450px;
  overflow-x: hidden;
}
.topics::after {
  position: absolute;
  content: "";
  display: block;
  background: url(../img/wave3.webp) no-repeat;
  background-position: bottom center;
  height: 322px;
  width: 100%;
  bottom: 0;
  left: 0;
}
@media screen and (max-width: 768px) {
  .history {
    padding-bottom: 200px;
  }
  .history::after {
    background-size: 107%;
    height: 150px;
  }
}
@media screen and (min-width: 1800px) {
  .history::before,
  .history::after,
  .topics::after {
    background-size: 100% 100%;
  }
}
.topics .img1,
.topics .img2,
.topics .img3,
.topics .img4,
.topics .img5,
.topics .img6,
.topics .img7 {
  z-index: 10;
  position: absolute;
  left: 50%;
  transition: transform 2s, 1s;
}
.topics .img1 {
  top: 0px;
  margin-left: -900px;
  animation: fluffy1 3s infinite;
}
.topics .img2 {
  top: 50px;
  margin-left: 650px;
  animation: fluffy2 3s infinite;
}
.topics .img3 {
  top: 450px;
  margin-left: -800px;
  animation: fluffy3 3s infinite;
}
.topics .img4 {
  top: 450px;
  margin-left: 600px;
  animation: fluffy4 3s infinite;
}
.topics .img5 {
  top: 950px;
  margin-left: 580px;
  animation: fluffy5 3s infinite;
}
.topics .img6 {
  top: 1000px;
  margin-left: -900px;
  animation: fluffy6 3s infinite;
}
.topics .img7 {
  top: 1700px;
  margin-left: -650px;
  animation: fluffy7 3s infinite;
}
.topics .img1.scroll {
  top: 100px;
}
.topics .img2.scroll {
  top: 150px;
}
.topics .img3.scroll {
  top: 550px;
}
.topics .img4.scroll {
  top: 550px;
}
.topics .img5.scroll {
  top: 1050px;
}
.topics .img6.scroll {
  top: 1100px;
}
.topics .img7.scroll {
  top: 1750px;
}
@keyframes fluffy1 {
  0%, 100% { top: 90px; }
  50% { top: 110px; }
}
@keyframes fluffy2 {
  0%, 100% { top: 140px; }
  50% { top: 160px; }
}
@keyframes fluffy3 {
  0%, 100% { top: 540px; }
  50% { top: 560px; }
}
@keyframes fluffy4 {
  0%, 100% { top: 540px; }
  50% { top: 560px; }
}
@keyframes fluffy5 {
  0%, 100% { top: 1040px; }
  50% { top: 1060px; }
}
@keyframes fluffy6 {
  0%, 100% { top: 1090px; }
  50% { top: 1110px; }
}
@keyframes fluffy7 {
  0%, 100% { top: 1740px; }
  50% { top: 1760px; }
}
.topics h3 {
  margin-top: 70px;
}
.topics .block {
  background: #FFF;
  border-radius: 80px;
  padding: 50px 40px;
  display: flex;
  position: relative;
  margin-top: 10px;
}
.topics .block .detail {
  text-align: left;
  padding-left: 50px;
}
.topics .block .detail .title {
  font-size: 2.7rem;
  margin-bottom: 30px;
}
.topics .block .detail .more {
  position: absolute;
  bottom: 30px;
  left: 0;
  width: 100%;
  text-align: center;
}
.topics .block .detail .more a {
  display: inline-block;
  padding: 8px 20px 10px 20px;
  border-radius: 30px;
  color: #FFF;
  background: red;
  font-size: 1.4rem;
}

.discover {
  padding: 100px 0;
  background: #FFF;
}
.discover ul {
  display: flex;
  gap: 0 20px;
  justify-content: space-between;
  text-align: left;
  padding: 0 15px;
  margin-top: 30px;
}
.discover ul li {
  width: calc(100% / 3 - 20px);
}
.discover ul li img {
  border-radius: 50px;
}
.discover ul li .title {
  margin-top: 30px;
  margin-bottom: 15px;
}
.discover ul li .more a {
  display: inline-block;
  background: red;
  color: #FFF;
  font-size: 1.4rem;
  padding: 8px 20px 10px 20px;
  border-radius: 30px;
}
li .thumbnail {
  overflow: hidden;
  border-radius: 30px;
}
li .thumbnail img {
  transition: transform .6s ease;
  overflow: hidden;
  height: auto;
  z-index: 10;
}
li .thumbnail img:hover {
  transform: scale(1.1);
}

footer {
  text-align: center;
  font-size: 1.2rem;
  padding: 50px 0 25px 0;
}
footer .logo img {
  width: 120px;
}
footer .copy {
  margin-top: 5px;
}

@media screen and (max-width: 768px) {
  body {
    background: none;
  }
  .inner {
    width: 100%;
    margin: 0 auto;
    padding: 0 15px;
  }
  header {
    display: flex;
    flex-wrap: wrap;
    padding: 19px 20px 0 13px;
  }
  header .logo {
    position: static;
    margin-bottom: 20px;
  }
  header .logo {
    max-width: 100px;
  }
  header h1.ani {
    margin-bottom: 0;
    width: 100%;
  }
  header h1.ani img {
    max-width: 50%;
  }
  header nav {
    margin-left: 20px;
  }
  header li {
    text-align: center;
  }
  main {
    background: url(../img/wave.webp) no-repeat;
    background-size: 120% auto;
    background-position: center top;
    animation: fluffy 3s infinite;
  }
  @keyframes fluffy {
    0%, 100% {
      background-position: center top;
    }
    50% {
      background-position: center 15px;
    }
  }
  .history .button {
    background-size: 90% auto;
    background-position: center top;
    padding: 100px 0 0 0;
    font-size: 1.3rem;
  }
  .history .button a {
    width: 80%;
    padding-left: 0;
    padding-right: 0;
  }
  .history .button a span {
    font-size: 2.0rem
  }
  .topics {
    padding-bottom: 200px;
  }
  .topics .block .detail {
    text-align: left;
    padding-left: 20px;
    display: flex;
    flex-direction: column;
  }
  .topics .block .detail .more {
    position: static;
    text-align: left;
    margin-top: 50px;
  }
  .topics .block .detail .more a {
    padding: 10px 50px;
  }
  .topics .block .detail .title {
    font-size: 2.0rem;
  }
  .topics::after {
    background-size: 107%;
    height: 200px;
   }
  .discover ul {
    flex-wrap: wrap;
    padding: 0 5%;
    gap: 0;
    width: 100%;
  }
  .discover ul li {
    width: 100%;
    margin-bottom: 40px;
  }
  .discover ul li .title {
    margin-top: 15px;
  }
  .discover ul li .more {
    text-align: center;
  }
  .discover ul li .more a {
    padding: 10px 50px;
  }
  .discover h2 img {
    max-width: 60%;
  }
  .discover {
    padding-bottom: 0;
  }
}

@media screen and (max-width: 500px) {
  main {
    padding-top: 280px;
  }
  .topics .block {
    flex-wrap: wrap;
    flex-direction: column;
    padding: 30px 20px;
    align-items: center;
  }
  .topics .block .thumbnail {
    text-align: center;
    margin-bottom: 20px;
  }
  .topics .block .detail {
    padding-left: 0;
  }
  .topics .block .detail .more {
    margin-top: 30px;
    text-align: center;
  }
  .history .button a span {
    font-size: 1.5rem;
  }
  .history .button a::after {
    width: 25px;
    height: 25px;
    margin-top: -12.5px;
    background-size: 100% auto;
  }
}

.youtube {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
}

.youtube video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

.topics .message {
  opacity: 0;
  visibility: hidden;
  transform: translate(0);
  transition: opacity 1s,visibility 1s, transform 1s;
}
h1.ani {
  opacity: 0;
  visibility: hidden;
  transform: translate(0);
  transition: opacity 3s, visibility 3s, transform 3s;
}
.topics .message .thumbnail {
  aspect-ratio: 1 / 1;
  width: 35%;
}
.topics .message .thumbnail img {
  border-radius: 50%;
  object-fit: contain;
  width: 100%;
  height: 100%;
}

main > .inner > p {
  opacity: 0;
  visibility: hidden;
  transform: translateY(50px);
  transition: opacity 1s,visibility 1s, transform 1s;
}

h1.ani.scroll,
main > .inner > p.scroll,
.topics .message.scroll {
  opacity: 1;
  visibility: visible;
  transform: translate(0px);
}

@media screen and (max-width: 768px) {
  .topics .message .thumbnail {
    aspect-ratio: 1 / 1;
    width: 100%;
  }
  .topics .message .thumbnail img {
    max-width: 100%;
  }
}