#aboutpage-timeline {
  position: relative;
  margin: 100px auto;
  max-width: 1200px;
}

.timeline-container {
  padding: 10px 50px;
  position: relative;
  width: 50%;
  opacity: 0;
  scale: 0.5;
  animation: appear ease forwards;
  animation-timeline: view();
  animation-range: entry 0% cover 30%;
}

@keyframes appear {
  form {
    opacity: 0;
    scale: 0.5;
  }
  to {
    opacity: 1;
    scale: 1;
  }
}

.timeline-container:nth-child(1) {
  animation-delay: 0s;
}
.timeline-container:nth-child(2) {
  animation-delay: 1s;
}
.timeline-container:nth-child(3) {
  animation-delay: 2s;
}
.timeline-container:nth-child(4) {
  animation-delay: 3s;
}

.text-box {
  padding: 20px 30px;
  position: relative;
  border-radius: 6px;
  font-size: 15px;
  background-color: #fdf7f4;
}

.timeline-container:nth-child(even) {
  left: 0;
}

.timeline-container:nth-child(odd) {
  left: 50%;
}

.timeline-container .dot {
  position: absolute;
  width: 20px;
  height: 20px;
  border: 2px solid orangered;
  background-color: white;
  border-radius: 50%;
  right: -10px;
  top: 32px;
  z-index: 1;
}

.timeline-container:nth-child(odd) .dot {
  left: -10px;
}

.timeline::after {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  width: 6px;
  height: 100%;
  background-color: #f2eff2;
  margin-left: -3px;
  z-index: -1;
  animation: moveline linear;
  animation-timeline: scroll();
  animation-range: entry 50% exit 90%;
}

@keyframes moveline {
  0% {
    height: 0%;
  }
  100% {
    height: 100%;
  }
}

.text-box .left-arrow {
  height: 0;
  width: 0;
  position: absolute;
  top: 28px;
  z-index: 1;
  border-top: 15px solid transparent;
  border-bottom: 15px solid transparent;
  border-left: 15px solid #fdf7f4;
  right: -15px;
}

.text-box .right-arrow {
  height: 0;
  width: 0;
  position: absolute;
  top: 28px;
  z-index: 1;
  border-top: 15px solid transparent;
  border-bottom: 15px solid transparent;
  border-right: 15px solid #fdf7f4;
  left: -15px;
}

/* responsive */

@media screen and (max-width: 600px) {
  .timeline {
    margin: 50px auto;
  }

  .timeline::after {
    left: 31px;
  }

  .timeline-container {
    width: 100%;
    padding-left: 80px;
    padding-right: 25px;
  }

  .timeline-container:nth-child(odd) {
    left: 0%;
  }

  .timeline-container .dot {
    left: 21px;
  }

  .timeline-container:nth-child(odd) .dot {
    left: 21px;
  }

  .left-arrow {
    transform: rotate(180deg);
    left: -15px;
  }
}