.heading {
    text-align: center;
    font-size: 4rem;
}

.about {
    background-color: var(--bg-color);
    margin: 12rem 10%;
}

.about h2 {
    margin-bottom: 5rem;
}

.timeline-items {
    max-width: 1200px;
    margin: auto;
    display: flex;
    flex-wrap: wrap;
    position: relative;
}

.timeline-items::before {
    content: "";
    position: absolute;
    width: 5px;
    height: 100%;
    background-color: var(--main-color);
    left: calc(50% - 1px);
}

.timeline-item {
    margin-bottom: 40px;
    width: 100%;
    position: relative;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-item:nth-child(odd){
    padding-right: calc(50% + 30px);
    text-align: right;
}

.timeline-item:nth-child(even){
    padding-left: calc(50% + 30px);
}

.timeline-dot{
    height: 21px;
    width: 21px;
    background-color: var(--main-color);
    box-shadow: 0 0 25px var(--main-color),
                0 0 50px var(--main-color);
    position: absolute;
    left: calc(50% - 8px);
    border-radius: 50%;
    top: 10px;
}

.timeline-date {
    font-size: 20px;
    font-weight: 800;
    color: var(--text-color);
    margin: 6px 0 15px;
}

.timeline-content {
    background-color: var(--second-bg-color);
    border: 3px solid var(--main-color);
    padding: 30px 50px;
    border-radius: 3rem;
    box-shadow: 0 0 10px var(--main-color);
    cursor: pointer;
    transition: .3s ease-in-out;
}

.timeline-content:hover {
    transform: scale(1.05);
    box-shadow: 0 0 25px var(--main-color);
}

.timeline-content h3 {
    font-size: 24px;
    color: var(--text-color);
    font-weight: 500;
}

.timeline-content h4 {
    font-size: 18px;
    font-style: italic;
    color: var(--text-color);
    margin: 0 0 10px;
    font-weight: 500;
}

.timeline-content p {
    color: var(--text-color);
    font-size: 16px;
    font-weight: 300;
    line-height: 22px;
    text-align: left;
}