.vertical-timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 0;
}
.vertical-timeline::after {
  content: '';
  position: absolute;
  width: 4px;
  background-color: var(--text-color);
  top: 0;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
}
.vertical-timeline-element {
  position: relative;
  width: 50%;
  padding: 20px 40px;
  box-sizing: border-box;
  opacity: 0;
  transition: all 0.6s ease-out;
}
.vertical-timeline-element.visible {
  opacity: 1;
  animation: fadeInUp 1s ease-out;
}
.vertical-timeline-element.left {
  left: 0;
  text-align: right;
}
.vertical-timeline-element.right {
  left: 50%;
  text-align: left;
}
.vertical-timeline-element .content {
  background: linear-gradient(145deg, #ffffff, #f8f9fa);
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.1);
  position: relative;
}
.vertical-timeline-element .date {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-color);
  margin-bottom: 10px;
}
.vertical-timeline-element.left::before,
.vertical-timeline-element.right::before {
  content: '';
  position: absolute;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background-color: var(--text-color);
  border: 3px solid #fff;
  top: 25px;
  z-index: 1;
}
.vertical-timeline-element.left::before {
  right: -11px;
}
.vertical-timeline-element.right::before {
  left: -11px;
}
@media screen and (max-width: 768px) {
  .vertical-timeline::after {
    left: 20px;
  }
  .vertical-timeline-element {
    width: 100%;
    padding-left: 60px;
    padding-right: 20px;
  }
  .vertical-timeline-element.left,
  .vertical-timeline-element.right {
    left: 0;
    text-align: left;
  }
  .vertical-timeline-element.left::before,
  .vertical-timeline-element.right::before {
    left: 8px;
  }
}