.about_area {
  width: 75vw;
  margin: auto;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  flex-direction: column;
  align-items: center;

}

.about_tit_area {
  display: flex;
  align-items: center;
  width: 100%;
  justify-content: center;
  position: relative;
  top: 50%;
  transform: translateY(-50%);
}

.about_tit {
  font-size: 2.43vw;
  color: rgba(0, 0, 0, 0.8);
  font-weight: 700;
}

.about_tit_br {
  display: none;
}

.about_sub_tit {
  font-size: 1.39vw;
  color: #ab6b00;
  font-weight: 700;
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
}

.about_txt {
  font-size: 1.39vw;
  font-weight: 700;
  color: rgba(0, 0, 0, 0.8);
  margin-bottom: 5%;
  text-align: center;
  width: 62.5vw;
}

.mission_img_area {
  display: flex;
  justify-content: space-between;
  width: 100%;
}

.mission_img {
  width: 20.37%;
}

.scroll {
  position: relative;
  background: transparent;
}

/* =========================
   Sticky Container
========================= */
.sticky {
  position: relative;
  height: auto;
  overflow: visible;
  background: transparent;
}

/* =========================
   Fade Panels
========================= */
.panel {
  position: sticky;
  top: 0;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background-color: rgba(255, 255, 255, 0.35);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(2.8rem);
  transition:
    opacity 0.55s ease,
    transform 0.55s ease,
    visibility 0s linear 0.55s;
  will-change: opacity, transform;
}

.panel.is-active {
  z-index: 4;
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
  transition:
    opacity 0.55s ease,
    transform 0.55s ease,
    visibility 0s;
}

.panel-1 {
  z-index: 1;
}

.panel-2 {
  z-index: 2;
}

.panel-3 {
  z-index: 3;
}

/* 暗転レイヤー */
.panel::after {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  /* 暗さの最大値 */
  opacity: 0;
  transition: opacity 0.2s linear;
  pointer-events: none;
}

/* ===== Text animation ===== */
.js-animate-text {
  overflow: hidden;
  opacity: 0;
}

.js-animate-text .letter {
  display: inline-block;
  opacity: 0;
  transform: scale(0.3);
}

/* 発火後 */
.js-animate-text.is-active {
  opacity: 1;
}

/* 下から“表示される”用（移動しない） */
.js-animate-item {
  opacity: 0;
  clip-path: inset(100% 0 0 0);
  transform: translateY(2rem);
  transition:
    clip-path 0.55s cubic-bezier(.2, .8, .2, 1),
    transform 0.75s cubic-bezier(.16, 1, .3, 1),
    opacity 0.75s cubic-bezier(.16, 1, .3, 1);
  will-change: clip-path;
}

/* 発火後 */
.js-animate-item.is-reveal {
  clip-path: inset(0 0 0 0);
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 48rem) {
  .sticky {
    position: static;
  }

  .panel {
    position: relative;
    top: auto;
    min-height: auto;
    align-items: center;
    padding: 4.8rem 2rem;
    background-color: rgba(255, 255, 255, 0.35);
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
    transition: none;
  }

  .panel+.panel {
    padding-top: 2.4rem;
  }

  .panel.is-active {
    z-index: auto;
    transform: none;
    transition: none;
  }

  .panel::after {
    display: none;
  }


  .about_area {
    position: static;
    transform: none;
    width: 100%;
    max-width: 40rem;
    margin: 0 auto;
    align-items: flex-start;
  }

  .about_tit_area {
    position: static;
    transform: none;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.8rem;
    margin-bottom: 1.8rem;
  }

  .about_sub_tit {
    position: static;
    transform: none;
    font-size: 1.2rem;
    letter-spacing: 0.16em;
  }

  .about_tit {
    font-size: clamp(2.4rem, 7vw, 3.2rem);
    line-height: 1.45;
  }

  .about_tit_br {
    display: block;
  }

  .about_txt {
    width: 100%;
    margin-bottom: 2.4rem;
    text-align: left;
    font-size: 1.4rem;
    line-height: 1.9;
  }

  .mission_img_area {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.2rem 1rem;
  }

  .mission_img {
    width: 100%;
  }
}