.timeline-section {
    --timeline-max-width: 960px;
    margin: 24px 0 48px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.timeline-title {
    text-align: left;
    font-weight: 600;
    color: #6b7280;
    margin-bottom: 4px;
    width: 100%;
    max-width: var(--timeline-max-width);
    display: flex;
    align-items: baseline;
    gap: 8px;
}

.timeline-subtitle {
    width: 100%;
    max-width: var(--timeline-max-width);
    color: #6b7280;
    font-size: 14px;
    line-height: 1.4;
    margin: 0 0 6px;
}

.timeline-title-left {
    display: inline-flex;
    align-items: baseline;
    gap: 8px;
}

.timeline-toggle {
    margin-left: auto;
    color: #9ca3af;
    display: inline-flex;
    align-items: center;
    cursor: pointer;
}

.timeline-toggle:hover {
    color: #6b7280;
}

.timeline-hint {
    font-size: 13px;
    color: #9ca3af;
    margin: 0;
    animation: timeline-hint-breathe 2.4s ease-in-out infinite;
}

@keyframes timeline-hint-breathe {
    0% { opacity: 0.55; }
    50% { opacity: 1; }
    100% { opacity: 0.55; }
}

.timeline-track {
    position: relative;
    padding: var(--timeline-padding-top, 20px) 12px 28px;
    --axis-y: 50%;
    --axis-color: #262626;
    --callout-gap-up: 14px;
    --callout-gap-down: 28px;
    --timeline-highlight: #fbbf24;
    --timeline-highlight-strong: #f59e0b;
    --timeline-highlight-shadow: rgba(245, 158, 11, 0.35);
    --timeline-highlight-shadow-fade: rgba(245, 158, 11, 0);
    width: 100%;
    max-width: var(--timeline-max-width);
    margin: 0 auto;
}

.timeline-track::before {
    content: "";
    position: absolute;
    left: 0;
    right: 10px;
    top: var(--axis-y);
    height: 2px;
    background: var(--axis-color);
    opacity: 0.6;
    transform: translateY(-50%);
}

.timeline-track::after {
    content: "";
    position: absolute;
    right: 0;
    top: var(--axis-y);
    width: 0;
    height: 0;
    border-left: 10px solid var(--axis-color);
    border-top: 5px solid transparent;
    border-bottom: 5px solid transparent;
    opacity: 0.6;
    transform: translateY(-50%);
}

.timeline-dot {
    width: 8px;
    height: 8px;
    background: var(--axis-color);
    border-radius: 50%;
    position: relative;
    z-index: 1;
    top: calc(var(--axis-y) - 4px);
    left: var(--mid);
    transform: translateX(-50%);
    pointer-events: auto;
}

.timeline-item {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
    z-index: 1;
    --reveal-order: 0;
}

.timeline-range {
    position: absolute;
    top: calc(var(--axis-y) - 4px);
    height: 8px;
    background: #cbd5e1;
    opacity: 0.5;
    border-radius: 999px;
    left: var(--start);
    width: var(--length);
}

.timeline-callout {
    position: absolute;
    max-width: none;
    white-space: nowrap;
    text-align: center;
    font-size: var(--callout-font-size, 14px);
    left: var(--mid);
    --callout-shift: 0px;
    transform: translateX(calc(-50% + var(--callout-shift)));
    pointer-events: auto;
    z-index: 1;
}

.timeline-callout::before {
    content: "";
    position: absolute;
    left: calc(50% - var(--callout-shift));
    width: 2px;
    height: 0;
    background: var(--axis-color);
    opacity: 0.6;
    transform: translateX(-50%);
}

/* Horizontal: label above axis (position 1) */
.timeline-item[data-position="1"] .timeline-callout {
    bottom: calc(var(--axis-y) + var(--callout-gap-up));
}

.timeline-item[data-position="1"] .timeline-callout::before {
    bottom: calc(-1 * var(--callout-gap-up));
    height: var(--callout-gap-up);
}

/* Horizontal: label below axis (position 2) */
.timeline-item[data-position="2"] .timeline-callout {
    top: calc(var(--axis-y) + var(--callout-gap-down));
}

.timeline-item[data-position="2"] .timeline-callout::before {
    top: calc(-1 * var(--callout-gap-down));
    height: var(--callout-gap-down);
}

.timeline-callout a {
    color: var(--axis-color);
    text-decoration: none;
    font-weight: 600;
}

.timeline-callout a:hover {
    text-decoration: underline;
}

.timeline-item.is-active .timeline-range {
    background: var(--timeline-highlight, #fbbf24);
    opacity: 0.85;
}

.timeline-item.is-active {
    z-index: 10;
}

.timeline-item.is-active .timeline-dot {
    background: var(--timeline-highlight-strong, #f59e0b);
}

.timeline-item.is-active .timeline-callout a {
    color: #111827;
    padding: 2px 8px;
    border-radius: 999px;
    position: relative;
    z-index: 1;
}

.timeline-item.is-active .timeline-callout a::before {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--timeline-highlight, #fbbf24);
    border-radius: inherit;
    z-index: -1;
    opacity: 1;
}

.timeline-item.is-active .timeline-callout {
    z-index: 11;
}

.timeline-item.timeline-activate-pulse .timeline-dot {
    animation: timeline-pulse 1.6s ease-in-out infinite;
}

.timeline-item.timeline-activate-pulse .timeline-range {
    animation: timeline-breathe 1.6s ease-in-out infinite;
}

.timeline-item.timeline-activate-pulse .timeline-callout a {
    animation: none;
}

.timeline-item.timeline-activate-pulse .timeline-callout a::before {
    animation: timeline-callout-breathe 1.6s ease-in-out infinite;
}

.timeline-track.timeline-reveal .timeline-item .timeline-dot {
    opacity: 0;
    animation: timeline-dot-reveal var(--timeline-reveal-duration, 320ms) ease-out forwards;
}

.timeline-track.timeline-reveal .timeline-item .timeline-range {
    opacity: 0;
    transform: scaleX(0);
    transform-origin: left center;
    animation: timeline-range-reveal var(--timeline-reveal-duration, 320ms) ease-out forwards;
}

.timeline-track.timeline-reveal .timeline-item .timeline-callout {
    opacity: 0;
    animation: timeline-callout-reveal var(--timeline-reveal-duration, 320ms) ease-out forwards;
}

.timeline-track.timeline-reveal .timeline-item .timeline-dot,
.timeline-track.timeline-reveal .timeline-item .timeline-range,
.timeline-track.timeline-reveal .timeline-item .timeline-callout {
    animation-delay: calc(var(--reveal-order, 0) * var(--timeline-reveal-step, 120ms));
}

@keyframes timeline-dot-reveal {
    0% {
        opacity: 0;
        transform: translateX(-50%) scale(0.6);
    }
    100% {
        opacity: 1;
        transform: translateX(-50%) scale(1);
    }
}

@keyframes timeline-range-reveal {
    0% {
        opacity: 0;
        transform: scaleX(0);
    }
    100% {
        opacity: 0.5;
        transform: scaleX(1);
    }
}

@keyframes timeline-callout-reveal {
    0% {
        opacity: 0;
        transform: translateX(calc(-50% + var(--callout-shift))) translateY(6px);
    }
    100% {
        opacity: 1;
        transform: translateX(calc(-50% + var(--callout-shift))) translateY(0);
    }
}

@keyframes timeline-pulse {
    0% { box-shadow: 0 0 0 0 var(--timeline-highlight-shadow, rgba(245, 158, 11, 0.35)); }
    70% { box-shadow: 0 0 0 8px var(--timeline-highlight-shadow-fade, rgba(245, 158, 11, 0)); }
    100% { box-shadow: 0 0 0 0 var(--timeline-highlight-shadow-fade, rgba(245, 158, 11, 0)); }
}

@keyframes timeline-breathe {
    0% { opacity: 0.35; }
    50% { opacity: 0.9; }
    100% { opacity: 0.35; }
}

@keyframes timeline-callout-breathe {
    0% { opacity: 0.2; }
    50% { opacity: 0.55; }
    100% { opacity: 0.2; }
}

.timeline-ticks {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(50% + 8px);
    height: 20px;
    pointer-events: none;
}

.timeline-tick {
    position: absolute;
    top: 0;
    transform: translateX(-50%);
    color: #a3a3a3;
    font-size: 12px;
    left: var(--tick);
}

.timeline-tick::before {
    content: "";
    position: absolute;
    top: -10px;
    left: 50%;
    width: 1px;
    height: 8px;
    background: #d4d4d4;
    transform: translateX(-50%);
}

@media (prefers-reduced-motion: reduce) {
    .timeline-hint,
    .timeline-item.timeline-activate-pulse .timeline-dot,
    .timeline-item.timeline-activate-pulse .timeline-range,
    .timeline-item.timeline-activate-pulse .timeline-callout a::before {
        animation: none !important;
    }
}