/* timeline.css */

/* Timeline Section */
.timeline-section {
    padding: 100px 0;
    background: #fff;
    position: relative;
}

.section-title {
    text-align: center;
    margin-bottom: 80px;
}

.section-title h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.section-title p {
    font-size: 1.2rem;
    color: #64748b;
    max-width: 600px;
    margin: 0 auto;
}

/* Year Filter */
.year-filter {
    text-align: center;
    margin-bottom: 60px;
}

.year-btn {
    background: white;
    border: 2px solid var(--secondary-color);
    color: #64748b;
    padding: 12px 24px;
    margin: 0 8px 10px;
    border-radius: 50px;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    display: inline-block;
    font-size: 1rem;
}

.year-btn:hover,
.year-btn.active {
    background: var(--secondary-color);
    border-color: var(--secondary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.3);
}

/* Desktop Timeline */
.desktop-timeline {
    display: none;
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
    position: relative;
}

.timeline-container {
    position: relative;
    padding: 80px 0 40px;
}

.timeline-line {
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    height: 2px;
    background: #ddd;
}

.timeline-progress {
    position: absolute;
    top: 60px;
    left: 0;
    height: 2px;
    background: linear-gradient(to right, var(--secondary-color), #e53e3e);
    width: 85%;
}

.timeline-grid {
    display: flex;
    justify-content: space-between;
    position: relative;
    z-index: 2;
    align-items: flex-start;
}

.timeline-period {
    flex: 1;
    position: relative;
    padding: 0 10px;
}

.period-header {
    font-size: 1.1rem;
    font-weight: 700;
    color: #666;
    margin-bottom: 30px;
    text-align: center;
    position: relative;
}

.period-header::after {
    content: '';
    position: absolute;
    bottom: -17px;
    left: 50%;
    transform: translateX(-50%);
    width: 8px;
    height: 8px;
    background: var(--secondary-color);
    border: 2px solid white;
    border-radius: 50%;
    box-shadow: 0 0 0 1px #ddd;
}

.timeline-events {
    text-align: center;
}

.timeline-event {
    margin-bottom: 20px;
}

.event-date {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 5px;
}

.event-title {
    font-size: 0.85rem;
    color: #2d3748;
    line-height: 1.3;
    font-weight: 500;
}

.event-desc {
    font-size: 0.8rem;
    color: #64748b;
    margin-top: 3px;
}

/* 2025년 이후 특별 스타일 */
.timeline-period.recent .period-header {
    color: #e53e3e;
}

.timeline-period.recent .period-header::after {
    background: #e53e3e;
}

.timeline-period.recent .event-date {
    color: #e53e3e;
}

/* Mobile Timeline */
.mobile-timeline {
    display: block;
    max-width: 600px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
}

.mobile-timeline-line {
    position: absolute;
    left: 20px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: #e2e8f0;
}

.mobile-period {
    margin-bottom: 60px;
}

.mobile-period-header {
    display: flex;
    align-items: center;
    margin-bottom: 30px;
    position: relative;
}

.mobile-period-dot {
    width: 12px;
    height: 12px;
    background: var(--secondary-color);
    border: 3px solid white;
    border-radius: 50%;
    margin-right: 20px;
    box-shadow: 0 0 0 2px #e2e8f0;
    flex-shrink: 0;
    position: relative;
    z-index: 2;
}

.mobile-period.recent .mobile-period-dot {
    background: #e53e3e;
}

.mobile-period-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: #666;
    margin: 0;
}

.mobile-period.recent .mobile-period-title {
    color: #e53e3e;
}

.mobile-events {
    padding-left: 32px;
}

.mobile-event {
    margin-bottom: 20px;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease;
}

.mobile-event.animate {
    opacity: 1;
    transform: translateY(0);
}

.mobile-event-date {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 5px;
}

.mobile-period.recent .mobile-event-date {
    color: #e53e3e;
}

.mobile-event-title {
    font-size: 1rem;
    color: #2d3748;
    line-height: 1.4;
    font-weight: 500;
}

.mobile-event-desc {
    font-size: 0.9rem;
    color: #64748b;
    margin-top: 3px;
}

/* Statistics */
.stats-summary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 60px 0;
    margin-top: 80px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    max-width: 800px;
    margin: 0 auto;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    display: block;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
    font-weight: 500;
}

/* Responsive Design */
@media (min-width: 992px) {
    .desktop-timeline {
        display: block;
    }

    .mobile-timeline {
        display: none;
    }
}

@media (max-width: 991px) {
    .timeline-section {
        padding: 60px 0;
    }

    .section-title h2 {
        font-size: 2rem;
    }
}

@media (max-width: 576px) {
    .year-btn {
        padding: 10px 18px;
        margin: 0 4px 8px;
        font-size: 0.9rem;
    }

    .mobile-events {
        padding-left: 24px;
    }
}