.challenges {
  position: relative;
  z-index: 1;
  background-color: #fff;
  padding: 4rem 0;
  overflow: hidden;
}

.challenges__header {
  display: grid;
  gap: 1.6rem;
  margin-bottom: 3.4rem;
  color: #000;
}

.challenges__list {
  margin: 0 -2rem 1.4rem;
  padding: 0 2rem;
  display: flex;
  gap: 1rem;
  overflow-x: auto;
}

.challenges__list::-webkit-scrollbar {
  display: none;
}

.challenges__item {
  aspect-ratio: 340 / 466;
  position: relative;
  width: 34rem;
  flex-shrink: 0;
  border-radius: 4rem;
  border: 1px solid #000;
  overflow: hidden;
}

.challenges__item-front {
  background-color: #fff;
  background-image: url(../assets/images/challenge-item-bg-m.webp);
  background-repeat: no-repeat;
  background-size: cover;
  padding: 4rem;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border-radius: 3rem;
}

.challenges__item-front-number {
  color: #000;
  font-family: "UAFSans";
  font-size: 4rem;
  font-style: normal;
  font-weight: 400;
  line-height: normal;
  letter-spacing: 0.16rem;
  text-transform: uppercase;
  text-align: center;
  display: block;
}

.challenges__item-back {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #000;
  z-index: 1;
  padding: 3rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.challenges__item-back-number {
  width: 4.4381rem;
  height: auto;
  position: relative;
  margin: 0 auto 7rem;
}

.challenges__item-back-number img {
  width: 100%;
  height: auto; 
}

.challenges__item-back-number span {
  position: absolute;
  bottom: -0.28rem;
  left: 3.52rem;
  color: #FFF;
  -webkit-text-stroke-width: 0.59px;
  -webkit-text-stroke-color: #FFF;
  font-family: "UAFSans";
  font-size: 1.769rem;
  font-style: normal;
  font-weight: 300;
  line-height: normal;
  letter-spacing: 0.0708rem;
  text-transform: uppercase;
}

.challenges__item-back-title {
  color: #FFF;
  text-align: center;
  font-family: "UAFSans";
  font-size: 1.7rem;
  font-style: normal;
  font-weight: 300;
  line-height: normal;
  letter-spacing: 0.068rem;
  text-transform: uppercase;
}

.challenges__item-back-text {
    color: #FFF;
  text-align: center;
  font-size: 1.6rem;
  font-style: normal;
  font-weight: 300;
  line-height: 140%;
  margin-top: auto;
}

.challenges__item-back-text strong {
  position: relative;
}

.challenges__item-back-text strong::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(150, 255, 173, 0.46);
  backdrop-filter: blur(3.5px);
}

.challenges__notice {
  color: #000;
  text-align: center;
}

@media (min-width: 768px) {
  .challenges {
    padding: 8rem 0 4.8rem;
  }

  .challenges__header {
    grid-template-columns: 41rem 1fr;
    align-items: center;
    margin-bottom: 5.8rem;
  }

  .challenges__list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 3.2rem;
    margin: 0;
    padding: 0;
    overflow: unset;
    margin-bottom: 2.4rem;
  }

  .challenges__item {
    width: 100%;
    height: 28rem;
    aspect-ratio: unset;
  }

  .challenges__item-front {
    background-image: url(../assets/images/challenge-item-bg-d.webp);
    padding: 7rem;
    align-items: center;
  }

  .challenges__item-front-number {
    text-align: left;
    font-size: 9.338rem;
    letter-spacing: 0.3735rem;
  }

  .challenges__item:hover .challenges__item-back {
    opacity: 1;
  }

  .challenges__item-back {
    overflow: hidden;
    position: relative;
    opacity: 0;
    transition: opacity 0.3s ease;
  }

  .challenges__item-back::after {
    content: '';
    position: absolute;
    top: -8rem;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url(../assets/images/challenge-back-bg-d.webp);
    background-repeat: no-repeat;
    background-position: center;
  }

  .challenges__item-back-number {
    margin-bottom: auto;
  }

  .challenges__item-back-number span{
    top: 50%;
    transform: translateY(-50%);
  }

  .challenges__notice {
    max-width: 51.5rem;
    font-size: 1.6rem;
    margin: 0 auto;
  }
}