.main-about-section {
  width: 100%;
  position: relative;
}

#main-about2 {
  height: 400vh;
}

/* sticky */

.main-about-container {
  position: sticky;
  top: 80px;
  height: calc(100vh - 80px);

  display: flex;
  align-items: center;
  justify-content: center;
}

/* slide */

.main-about-slide {
  position: absolute;

  display: flex;
  align-items: center;
  justify-content: space-between;

  width: 1200px;
  left: 50%;
  transform: translate(-50%, 0);

  gap: 120px;

  opacity: 0;
  pointer-events: none;
  transition: opacity 0.6s;
}

.main-about-slide.active {
  opacity: 1;
  pointer-events: auto;
  z-index: 3;
}

/* text */

.main-about-txt {
  max-width: 520px;
}

.main-about-txt h2 {
  color: #ff3b3b;
  font-size: 32px;
  font-weight: 600;
  margin-bottom: 12px;
}

.main-about-txt h3 {
  font-size: 40px;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 20px;
}

.main-about-txt p {
  font-size: 16px;
  line-height: 1.6;
  color: #555;
}

/* image */

.main-about-img {
  position: relative;
  width: 360px;
  height: 480px;
}

.main-about-img img {
  position: absolute;
  width: 360px;

  opacity: 0;
  transform: scale(0.8);

  transition:
    transform 0.6s ease,
    filter 0.6s ease,
    opacity 0.6s ease;
}

/* previous image */

.main-about-slide.prev .main-about-img img {
  opacity: 0.4;
  transform: translateX(-120px) scale(0.85);
  filter: blur(8px);
  z-index: 1;
}

/* active image */

.main-about-slide.active .main-about-img img {
  opacity: 1;
  transform: translateX(0) scale(1);
  filter: none;
  z-index: 3;
}

/* next image */

.main-about-slide.next .main-about-img img {
  opacity: 0.4;
  transform: translateX(120px) scale(0.85);
  filter: blur(8px);
  z-index: 1;
}

/* ---------------- MOBILE ---------------- */

@media (max-width: 900px) {
  #main-about2 {
    height: 360vh;
  }

  .main-about-slide {
    position: absolute;

    flex-direction: column;

    align-items: center;
    justify-content: center;

    text-align: center;

    width: 90%;

    left: 50%;
    transform: translate(-50%, 0);

    gap: 28px;
    will-change: opacity, transform;
  }

  .main-about-txt {
    max-width: 100%;
  }

  .main-about-img {
    width: 240px;
    height: auto;

    display: flex;
    justify-content: center;
    backface-visibility: hidden;
    transform: translateZ(0);
  }

  /* 모바일에서는 이미지 absolute 제거 */

  .main-about-img img {
    position: relative;
    width: 240px;

    opacity: 1;
    transform: none;
    filter: none;
  }

  /* blur 효과 모바일에서는 제거 */

  .main-about-slide.prev .main-about-img img,
  .main-about-slide.next .main-about-img img {
    display: none;
  }

  .main-about-txt h2 {
    font-size: 24px;
  }

  .main-about-txt h3 {
    font-size: 22px;
  }

  .main-about-txt p {
    font-size: 14px;
  }
}