/* Page Header */
.page-header {
    padding: calc(var(--header-height) + var(--space-96)) 0 var(--space-96);
    text-align: center;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.page-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100%;
    max-width: 1400px;
    height: 100%;
    background: radial-gradient(circle at 50% 0%, rgba(99, 102, 241, 0.08) 0%, transparent 60%);
    pointer-events: none;
}

.page-label {
    font-family: var(--font-mono);
    font-size: var(--font-xs);
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-16);
}

.page-title {
    font-size: var(--font-5xl);
    font-weight: var(--weight-black);
    margin-bottom: var(--space-16);
    position: relative;
    z-index: 1;
}

.page-desc {
    font-size: var(--font-lg);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
    position: relative;
    z-index: 1;
}

/* Timeline Section */
.timeline-section {
    padding: var(--space-128) 0;
}

.timeline {
    position: relative;
    max-width: 900px;
    margin: 0 auto;
}

/* Timeline Vertical Line */
.timeline::before {
    content: '';
    position: absolute;
    left: 100px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(
        180deg,
        transparent 0%,
        var(--border) 5%,
        var(--border) 95%,
        transparent 100%
    );
}

/* Timeline Item */
.timeline-item {
    position: relative;
    margin-bottom: var(--space-96);
    opacity: 0;
    animation: fadeIn 0.8s var(--transition-base) forwards;
}

.timeline-item:nth-child(1) { animation-delay: 0.1s; }
.timeline-item:nth-child(2) { animation-delay: 0.2s; }
.timeline-item:nth-child(3) { animation-delay: 0.3s; }
.timeline-item:nth-child(4) { animation-delay: 0.4s; }
.timeline-item:nth-child(5) { animation-delay: 0.5s; }
.timeline-item:nth-child(6) { animation-delay: 0.6s; }

.timeline-year {
    position: absolute;
    left: 0;
    top: 0;
    font-size: var(--font-4xl);
    font-weight: var(--weight-black);
    font-family: var(--font-mono);
    color: var(--text-primary);
    width: 80px;
    text-align: right;
}

/* Year Dot */
.timeline-year::after {
    content: '';
    position: absolute;
    right: -26px;
    top: 50%;
    transform: translateY(-50%);
    width: 12px;
    height: 12px;
    background: var(--text-primary);
    border-radius: var(--radius-full);
    box-shadow: 0 0 0 4px var(--bg), 0 0 0 6px var(--border);
    transition: all var(--transition-base);
}

.timeline-item:hover .timeline-year::after {
    background: var(--accent-primary);
    box-shadow: 0 0 0 4px var(--bg), 0 0 0 6px var(--accent-primary), var(--shadow-glow);
}

/* Timeline Events Container */
.timeline-events {
    margin-left: 140px;
    display: flex;
    flex-direction: column;
    gap: var(--space-32);
}

/* Timeline Event */
.timeline-event {
    position: relative;
    padding: var(--space-24);
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
}

.timeline-event::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl) 0 0 var(--radius-xl);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.timeline-event:hover {
    transform: translateX(8px);
    border-color: var(--border-light);
    box-shadow: var(--shadow-lg);
}

.timeline-event:hover::before {
    opacity: 1;
}

.timeline-date {
    font-family: var(--font-mono);
    font-size: var(--font-xs);
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: var(--space-12);
}

.timeline-content h3 {
    font-size: var(--font-xl);
    font-weight: var(--weight-bold);
    margin-bottom: var(--space-8);
    color: var(--text-primary);
}

.timeline-content p {
    font-size: var(--font-base);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Responsive */
@media (max-width: 768px) {
    .timeline::before {
        left: 20px;
    }
    
    .timeline-year {
        position: relative;
        width: 100%;
        text-align: left;
        margin-bottom: var(--space-16);
        padding-left: 40px;
    }
    
    .timeline-year::after {
        left: 14px;
        right: auto;
    }
    
    .timeline-events {
        margin-left: 40px;
    }
    
    .timeline-item {
        margin-bottom: var(--space-64);
    }
    
    .page-title {
        font-size: var(--font-4xl);
    }
}

@media (max-width: 640px) {
    .timeline-section {
        padding: var(--space-96) 0;
    }
    
    .timeline-event {
        padding: var(--space-16);
    }
    
    .timeline-content h3 {
        font-size: var(--font-lg);
    }
    
    .page-title {
        font-size: var(--font-3xl);
    }
}