.about-page {
    padding: 60px 0;
}

.company-intro {
    margin-bottom: 50px;
}

.history-timeline {
    position: relative;
    padding-left: 30px;
    margin: 40px 0;
}

.history-timeline::before {
    content: '';
    position: absolute;
    left: 7px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--primary-color);
}

.timeline-item {
    position: relative;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px dashed #eee;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -33px;
    top: 5px;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    border: 3px solid var(--light-color);
}

.timeline-year {
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.certificates {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.certificate-item {
    text-align: center;
    padding: 15px;
    background: #fff;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.certificate-item img {
    max-width: 100px;
    margin-bottom: 10px;
}

.back-btn {
    display: inline-block;
    margin-bottom: 30px;
    padding: 10px 20px;
    background-color: var(--primary-color);
    color: white;
    border-radius: 4px;
    text-decoration: none;
    transition: var(--transition);
}

.back-btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
}