/* Nav Sekou Section */
.nav-sekou {
  padding: 90px 0 60px;
  background-color: #fff;
  position: relative;
}

.nav-sekou::before {
  content: "";
  position: absolute;
  top: -40px;
  left: calc(50% - 650px);
  width: 620px;
  bottom: 0;
  background-image: url(../img/instruction/nav-sekou-bg.webp);
  background-size: 620px;
  background-position: center;
  background-repeat: no-repeat;
  z-index: 0;
  -webkit-clip-path: polygon(0% 0%, 0% 100%, 0% 100%, 0% 0%);
  clip-path: polygon(0% 0%, 0% 100%, 0% 100%, 0% 0%);
  transition: clip-path 1s ease-out;
  contain: layout style paint;
}

.nav-sekou.visible::before {
  -webkit-clip-path: polygon(0% 0%, 0% 100%, 100% 100%, 100% 0%);
  clip-path: polygon(0% 0%, 0% 100%, 100% 100%, 100% 0%);
}

.nav-sekou .container {
  position: relative;
  z-index: 1;
}

.nav-sekou .nav-list,
.nav-sekou .nav-note {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.nav-sekou.visible .nav-list,
.nav-sekou.visible .nav-note {
  opacity: 1;
  transform: translateY(0);
  transition-delay: 1s;
}

.nav-sekou .nav-list {
  display: flex;
  justify-content: space-between;
  list-style: none;
  padding: 0;
  margin: 0 0 20px;
}

.nav-sekou .nav-item {
  width: 45.5%;
}

.nav-sekou .nav-item a {
  display: block;
  text-decoration: none;
  position: relative;
  transition: opacity 0.3s;
}

.nav-sekou .nav-item a:hover {
  opacity: 0.8;
}

.nav-sekou .nav-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.nav-sekou .nav-item-text-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  background-color: #6894d1;
  height: 50px;
  padding: 9px 30px;
}

.nav-sekou .nav-text {
  color: #fff;
  text-align: center;
  font-family: "Noto Serif JP";
  font-size: 18px;
  font-style: normal;
  font-weight: 500;
  line-height: 2; /* 177.778% */
}

.nav-sekou .nav-arrow {
  width: 20px;
  height: auto;
  filter: brightness(0) invert(1); /* Make white */
}

.nav-sekou .nav-note {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 16px;
  font-style: normal;
  font-weight: 500;
  line-height: 32px; /* 200% */
}

@media (max-width: 1200px) {
  /* Nav Sekou Section */
  .nav-sekou::before {
    width: 52vw;
    background-size: 52vw;
    left: calc(50vw - 54vw);
    top: 3.3vw;
  }

  .nav-sekou .container {
    padding: 0 4vw;
  }
}

@media (max-width: 767px) {
  .nav-sekou {
    padding: 10vw 0 4vw;
    overflow: hidden;
    max-width: 100%;
  }
  .nav-sekou .container {
    padding: 0 5vw;
    overflow: hidden;
    max-width: 100%;
  }
  .nav-sekou::before {
    width: 160vw;
    left: 50%;
    transform: translateX(-50%);
    top: -50vw;
    background-size: 160vw;
  }
  .nav-sekou .nav-list {
    flex-direction: column;
    gap: 10vw;
    margin-bottom: 5vw;
  }
  .nav-sekou .nav-item {
    width: 100%;
  }
  .nav-sekou .nav-image {
    height: 36vw;
  }
  .nav-sekou .nav-item-text-box {
    height: 13vw;
    padding: 1vw 9vw;
  }
  .nav-sekou .nav-text {
    font-size: 4.5vw;
  }
  .nav-sekou .nav-arrow {
    width: 5vw;
  }
  .nav-sekou .nav-note {
    font-size: 3.8vw;
    line-height: 1.8;
  }
}

/* Instructions Section */
.instructions {
  padding: 30px 0 60px;
  background-color: #f0f4fa;
}

.instructions-title,
.youtube-title {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 40px;
  font-weight: 500;
  line-height: 1.2;
  margin-bottom: 10px;
}

.instructions-subtitle,
.youtube-subtitle {
  color: #6894d1;
  font-family: "Noto Sans JP";
  font-size: 24px;
  font-weight: 300;
  line-height: 1.2;
  margin-bottom: 35px;
  margin-top: 0;
}

.instructions-list {
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.instructions-item {
  display: flex;
  flex-direction: column;
}

.instructions-link {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 20px;
  font-weight: 700;
  line-height: 1.6;
  text-decoration: underline;
  transition: opacity 0.3s;
}

.instructions-link:hover {
  opacity: 0.7;
}

.instructions-text {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 16px;
  font-weight: 500;
  line-height: 2;
  margin: 0;
}

@media (max-width: 1200px) {
  .instructions .container {
    padding: 0 4vw;
  }
}

@media (max-width: 767px) {
  .instructions {
    padding: 2vw 0 9vw;
  }
  .instructions .container {
    padding: 0 5vw;
  }
  .instructions-title,
  .youtube-title {
    font-size: 5.2vw;
  }
  .instructions-subtitle,
  .youtube-subtitle {
    font-size: 4.2vw;
  }
  .instructions-list {
    gap: 6vw;
  }
  .instructions-link {
    font-size: 3.7vw;
  }
  .instructions-text {
    font-size: 3.7vw;
    line-height: 1.7;
  }
}

/* YouTube Section */
.youtube {
  padding: 30px 0 80px;
  background-color: #fff;
  position: relative;
  overflow: hidden;
}

.youtube-bg {
  position: absolute;
  top: 140px;
  left: calc(50% + 300px);
  width: 600px;
  aspect-ratio: 600/600;
  background-image: url(../img/instruction/yt-bg.webp);
  background-size: 600px;
  background-position: center;
  background-repeat: no-repeat;
  z-index: 0;
}

.youtube .container {
  position: relative;
  z-index: 1;
}

.youtube-intro {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 16px;
  font-style: normal;
  font-weight: 500;
  line-height: 2; /* 200% */
}

.youtube-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 60px 3.5%;
}

.youtube-item {
  display: flex;
  flex-direction: column;
}

.youtube-iframe {
  width: 100%;
  aspect-ratio: 16/9;
  border: none;
}

.youtube-caption-title {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 20px;
  font-style: normal;
  font-weight: 700;
  line-height: 28px; /* 140% */
  margin-bottom: 0;
}

.youtube-caption-text {
  color: #000;
  font-family: "Noto Serif JP";
  font-size: 16px;
  font-style: normal;
  font-weight: 500;
  line-height: 28px;
  margin-bottom: 0;
  margin-top: 0;
}

@media (max-width: 1200px) {
  .youtube .container {
    padding: 0 4vw;
  }

  .youtube-bg {
    width: 50vw;
    left: calc(50vw + 25vw);
    top: 12vw;
    background-size: 50vw;
  }
}


@media (max-width: 767px) {
  .youtube {
    padding: 5vw 0 15vw;
    overflow: hidden;
    max-width: 100%;
  }
  .youtube-subtitle {
    margin-bottom: 3vw;
  }
  .youtube .container {
    padding: 0 5vw;
    overflow: hidden;
    max-width: 100%;
  }
  .youtube-bg {
    width: 90vw;
    left: 95%;
    transform: translateX(-50%);
    top: 20vw;
    background-size: 90vw;
  }
  .youtube-intro {
    font-size: 3.7vw;
    margin-top: 0;
    line-height: 1.6;
  }
  .youtube-list {
    gap: 6vw;
    grid-template-columns: 1fr;
  }
  .youtube-item {
    width: 100%;
  }
  .youtube-caption-title {
    margin-top: 5vw;
    font-size: 3.7vw;
    margin-bottom: 1vw;
  }
  .youtube-caption-text {
    font-size: 3.5vw;
    padding-left: 1.1em;
  }
  .youtube-caption-text {
    line-height: 1.7;
  }
}