/* =========================================
   KHRONOS TIMELINE COMPONENT STYLES
   ========================================= */

/* Color Palette */
:root {
  --timeline-primary: #4169e1;
  --timeline-primary-light: #6a8eff;
  --timeline-primary-dark: #1e3a8a;
  --timeline-sepia: #d4a574;
  --timeline-cyan: #00d9ff;
  --timeline-dark-bg: #0a0e27;
  --timeline-card-bg: #0f1629;
  --timeline-text-primary: #e8eaed;
  --timeline-text-secondary: #b0b5c0;
  --timeline-border: #1e293b;
  --timeline-accent: #fbbf24;
  --timeline-glow: rgba(65, 105, 225, 0.6);
}

/* =========================================
   TIMELINE CONTAINER & LAYOUT
   ========================================= */

.timeline {
  position: relative;
  width: 100%;
  background: linear-gradient(180deg, var(--timeline-dark-bg) 0%, #0d1117 100%);
  overflow-x: hidden;
  overflow-y: auto;
  scroll-behavior: smooth;
  scroll-snap-type: y mandatory;
}

/* Desktop: Vertical timeline */
@media (min-width: 1024px) {
  .timeline {
    min-height: 100vh;
    padding: 4rem 2rem;
  }
}

/* Mobile: Horizontal timeline */
@media (max-width: 1023px) {
  .timeline {
    display: flex;
    flex-direction: row;
    overflow-x: auto;
    overflow-y: hidden;
    scroll-snap-type: x mandatory;
    padding: 2rem 0;
    min-height: auto;
    height: auto;
  }
}

/* Timeline fixed header */
.timeline-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, var(--timeline-dark-bg) 0%, rgba(10, 14, 39, 0.95) 100%);
  backdrop-filter: blur(8px);
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--timeline-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.timeline-header h1 {
  margin: 0;
  font-size: 1.75rem;
  font-weight: 700;
  background: linear-gradient(90deg, var(--timeline-sepia) 0%, var(--timeline-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.timeline-controls {
  display: flex;
  gap: 1rem;
  align-items: center;
}

/* =========================================
   TIMELINE TRACK & CENTER LINE
   ========================================= */

.timeline-track {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
}

/* Vertical line (desktop) */
.timeline-line {
  position: absolute;
  width: 2px;
  height: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(
    180deg,
    transparent 0%,
    var(--timeline-primary) 20%,
    var(--timeline-primary) 80%,
    transparent 100%
  );
  box-shadow: 0 0 20px var(--timeline-glow);
  pointer-events: none;
}

@media (max-width: 1023px) {
  .timeline-line {
    width: 100%;
    height: 2px;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    background: linear-gradient(
      90deg,
      transparent 0%,
      var(--timeline-primary) 20%,
      var(--timeline-primary) 80%,
      transparent 100%
    );
  }
}

/* =========================================
   TIMELINE NODES & MARKERS
   ========================================= */

.timeline-node {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 4rem;
  scroll-snap-align: center;
  animation: nodeEnter 0.6s ease-out forwards;
  opacity: 0;
}

@media (max-width: 1023px) {
  .timeline-node {
    flex-direction: column;
    margin-bottom: 0;
    margin-right: 4rem;
    scroll-snap-align: start;
    flex-shrink: 0;
  }
}

@keyframes nodeEnter {
  from {
    opacity: 0;
    transform: scale(0.8);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* Alternating layout on desktop */
.timeline-node:nth-child(odd) {
  flex-direction: row;
}

.timeline-node:nth-child(even) {
  flex-direction: row-reverse;
}

@media (max-width: 1023px) {
  .timeline-node:nth-child(odd),
  .timeline-node:nth-child(even) {
    flex-direction: column;
  }
}

/* Timeline marker (the dot) */
.timeline-marker {
  position: relative;
  width: 24px;
  height: 24px;
  background: var(--timeline-primary);
  border: 3px solid var(--timeline-dark-bg);
  border-radius: 50%;
  box-shadow:
    0 0 20px var(--timeline-glow),
    inset 0 0 10px rgba(255, 255, 255, 0.2);
  flex-shrink: 0;
  z-index: 10;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  cursor: pointer;
}

/* Pulsing animation for active node */
.timeline-marker.active {
  width: 32px;
  height: 32px;
  animation: nodePulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
  box-shadow:
    0 0 30px var(--timeline-primary),
    0 0 50px var(--timeline-glow),
    inset 0 0 10px rgba(255, 255, 255, 0.3);
}

@keyframes nodePulse {
  0%,
  100% {
    box-shadow:
      0 0 30px var(--timeline-primary),
      0 0 50px var(--timeline-glow),
      inset 0 0 10px rgba(255, 255, 255, 0.3);
  }
  50% {
    box-shadow:
      0 0 40px var(--timeline-primary),
      0 0 70px var(--timeline-glow),
      inset 0 0 15px rgba(255, 255, 255, 0.4);
  }
}

/* Hover state */
.timeline-marker:hover {
  width: 32px;
  height: 32px;
  box-shadow:
    0 0 30px var(--timeline-primary),
    0 0 50px var(--timeline-glow),
    inset 0 0 10px rgba(255, 255, 255, 0.3);
  transform: scale(1.1);
}

/* Inner glow circle */
.timeline-marker::before {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.4), transparent);
  pointer-events: none;
}

/* Milestone-specific marker */
.timeline-marker.milestone {
  background: linear-gradient(135deg, var(--timeline-sepia) 0%, var(--timeline-accent) 100%);
  box-shadow:
    0 0 20px rgba(251, 191, 36, 0.6),
    inset 0 0 10px rgba(255, 255, 255, 0.3);
}

.timeline-marker.milestone:hover {
  box-shadow:
    0 0 30px rgba(251, 191, 36, 0.8),
    0 0 50px rgba(251, 191, 36, 0.4),
    inset 0 0 10px rgba(255, 255, 255, 0.4);
}

/* =========================================
   ERA CARDS
   ========================================= */

.era-card {
  position: relative;
  width: calc(50% - 2rem);
  padding: 2rem;
  background: linear-gradient(135deg, var(--timeline-card-bg) 0%, rgba(15, 22, 41, 0.8) 100%);
  border: 1px solid var(--timeline-border);
  border-radius: 12px;
  margin: 0 1rem;
  scroll-snap-align: start;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  animation: cardSlideIn 0.6s ease-out forwards;
  opacity: 0;
  cursor: pointer;
  overflow: hidden;
}

@media (max-width: 1023px) {
  .era-card {
    width: 85vw;
    margin: 0;
    flex-shrink: 0;
  }
}

@keyframes cardSlideIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Card background gradient animation */
.era-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(45deg, rgba(65, 105, 225, 0.1) 0%, rgba(0, 217, 255, 0.05) 100%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
  border-radius: 12px;
}

/* Card hover state */
.era-card:hover,
.era-card.active {
  border-color: var(--timeline-primary);
  box-shadow:
    0 8px 32px var(--timeline-glow),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
  transform: translateY(-8px);
}

.era-card:hover::before,
.era-card.active::before {
  opacity: 1;
}

/* Card expansion animation */
.era-card.expanded {
  max-height: 600px;
}

/* Card inner content */
.era-card-content {
  position: relative;
  z-index: 1;
}

/* =========================================
   CARD SECTIONS (HEADER, BODY, FOOTER)
   ========================================= */

.era-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1.5rem;
  gap: 1rem;
}

.era-card-title {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--timeline-text-primary);
  line-height: 1.2;
}

.era-card-subtitle {
  margin: 0.5rem 0 0 0;
  font-size: 0.95rem;
  color: var(--timeline-text-secondary);
  font-weight: 500;
}

.era-card-badge {
  display: inline-block;
  padding: 0.4rem 0.8rem;
  background: linear-gradient(90deg, var(--timeline-sepia), var(--timeline-accent));
  color: #000;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
  flex-shrink: 0;
}

.era-card-body {
  margin: 1.5rem 0;
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--timeline-text-secondary);
}

.era-card-body p {
  margin: 0 0 1rem 0;
}

.era-card-body p:last-child {
  margin-bottom: 0;
}

.era-card-footer {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--timeline-border);
  font-size: 0.85rem;
  color: var(--timeline-text-secondary);
}

.era-card-footer-item {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* =========================================
   DATE LABELS
   ========================================= */

.timeline-date {
  position: absolute;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--timeline-primary);
  white-space: nowrap;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-shadow: 0 0 10px rgba(65, 105, 225, 0.3);
  pointer-events: none;
}

@media (min-width: 1024px) {
  .timeline-date {
    top: -2.5rem;
    left: 50%;
    transform: translateX(-50%);
  }
}

@media (max-width: 1023px) {
  .timeline-date {
    position: static;
    display: block;
    margin-bottom: 0.5rem;
    text-align: center;
  }
}

/* =========================================
   CONNECTING LINES & PATHS
   ========================================= */

.timeline-connector {
  position: absolute;
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, var(--timeline-primary) 50%, transparent 100%);
  box-shadow: 0 0 10px var(--timeline-glow);
  z-index: 5;
}

@media (min-width: 1024px) {
  .timeline-connector {
    top: 50%;
    width: calc(50% - 32px);
  }

  .timeline-node:nth-child(odd) .timeline-connector {
    right: -100%;
    transform: translateX(0);
  }

  .timeline-node:nth-child(even) .timeline-connector {
    left: -100%;
    transform: translateX(0);
  }
}

@media (max-width: 1023px) {
  .timeline-connector {
    display: none;
  }
}

/* =========================================
   MILESTONE MARKERS (SPECIAL EVENTS)
   ========================================= */

.milestone-marker {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: linear-gradient(135deg, rgba(251, 191, 36, 0.1) 0%, rgba(255, 255, 255, 0.05) 100%);
  border: 1px solid rgba(251, 191, 36, 0.4);
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--timeline-accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: all 0.3s ease;
}

.milestone-marker::before {
  content: '★';
  font-size: 0.9rem;
}

.milestone-marker:hover {
  background: linear-gradient(135deg, rgba(251, 191, 36, 0.2) 0%, rgba(255, 255, 255, 0.1) 100%);
  border-color: rgba(251, 191, 36, 0.7);
  box-shadow: 0 0 15px rgba(251, 191, 36, 0.3);
}

/* =========================================
   ZOOM CONTROLS
   ========================================= */

.timeline-zoom-controls {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  background: rgba(15, 22, 41, 0.6);
  border: 1px solid var(--timeline-border);
  border-radius: 8px;
  padding: 0.5rem;
  backdrop-filter: blur(4px);
}

.zoom-button {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--timeline-border);
  border-radius: 6px;
  color: var(--timeline-text-secondary);
  cursor: pointer;
  font-size: 1rem;
  font-weight: 700;
  transition: all 0.3s ease;
}

.zoom-button:hover {
  background: var(--timeline-primary);
  border-color: var(--timeline-primary);
  color: #fff;
  box-shadow: 0 0 15px var(--timeline-glow);
}

.zoom-button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.zoom-slider {
  width: 100px;
  height: 4px;
  accent-color: var(--timeline-primary);
  cursor: pointer;
}

.zoom-slider::-webkit-slider-thumb {
  appearance: none;
  width: 16px;
  height: 16px;
  background: var(--timeline-primary);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 0 10px var(--timeline-glow);
}

.zoom-slider::-moz-range-thumb {
  width: 16px;
  height: 16px;
  background: var(--timeline-primary);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 0 10px var(--timeline-glow);
  border: none;
}

/* =========================================
   MINI-MAP NAVIGATION
   ========================================= */

.timeline-minimap {
  position: fixed;
  right: 2rem;
  top: 50%;
  transform: translateY(-50%);
  width: 80px;
  height: 300px;
  background: linear-gradient(180deg, var(--timeline-card-bg) 0%, rgba(15, 22, 41, 0.9) 100%);
  border: 1px solid var(--timeline-border);
  border-radius: 12px;
  padding: 0.75rem;
  z-index: 50;
  box-shadow: 0 8px 32px var(--timeline-glow);
  backdrop-filter: blur(8px);
}

@media (max-width: 1023px) {
  .timeline-minimap {
    position: fixed;
    right: auto;
    left: 50%;
    bottom: 2rem;
    top: auto;
    transform: translateX(-50%);
    width: 300px;
    height: 80px;
    flex-direction: row;
  }
}

.minimap-track {
  position: relative;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, rgba(65, 105, 225, 0.1) 0%, rgba(0, 217, 255, 0.05) 100%);
  border-radius: 8px;
  overflow: hidden;
}

.minimap-dot {
  position: absolute;
  width: 6px;
  height: 6px;
  background: var(--timeline-primary);
  border-radius: 50%;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0.6;
  transition: all 0.3s ease;
  cursor: pointer;
}

.minimap-dot:hover {
  opacity: 1;
  transform: translateX(-50%) scale(1.3);
  box-shadow: 0 0 10px var(--timeline-glow);
}

.minimap-dot.active {
  opacity: 1;
  background: var(--timeline-cyan);
  box-shadow: 0 0 15px rgba(0, 217, 255, 0.6);
}

.minimap-viewport {
  position: absolute;
  width: 100%;
  height: 20%;
  border: 2px solid var(--timeline-primary);
  border-radius: 4px;
  pointer-events: none;
  box-shadow: inset 0 0 10px rgba(65, 105, 225, 0.2);
}

/* =========================================
   ICONS & DECORATIVE ELEMENTS
   ========================================= */

.timeline-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, rgba(65, 105, 225, 0.2) 0%, rgba(0, 217, 255, 0.1) 100%);
  border: 1px solid var(--timeline-border);
  border-radius: 8px;
  color: var(--timeline-cyan);
  font-size: 1rem;
  transition: all 0.3s ease;
}

.era-card:hover .timeline-icon,
.era-card.active .timeline-icon {
  background: linear-gradient(135deg, rgba(65, 105, 225, 0.3) 0%, rgba(0, 217, 255, 0.2) 100%);
  border-color: var(--timeline-cyan);
  transform: rotate(10deg) scale(1.1);
}

/* =========================================
   SCROLL ANIMATIONS & STATES
   ========================================= */

.timeline-node {
  /* Stagger animation based on position */
}

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

/* Intersection observer animation (for scroll-in) */
.timeline-node.in-view {
  animation: nodeEnter 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

.timeline-node.in-view .era-card {
  animation: cardSlideIn 0.6s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

/* =========================================
   FADE & EXPANSION ANIMATIONS
   ========================================= */

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes fadeOut {
  from {
    opacity: 1;
  }
  to {
    opacity: 0;
  }
}

@keyframes expandHeight {
  from {
    max-height: 200px;
    opacity: 0.8;
  }
  to {
    max-height: 600px;
    opacity: 1;
  }
}

.era-card.expanding {
  animation: expandHeight 0.4s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

/* =========================================
   RESPONSIVE ADJUSTMENTS
   ========================================= */

@media (max-width: 768px) {
  .timeline-header {
    padding: 1rem;
  }

  .timeline-header h1 {
    font-size: 1.3rem;
  }

  .timeline-controls {
    gap: 0.5rem;
  }

  .era-card {
    width: 90vw;
    padding: 1.5rem;
  }

  .era-card-title {
    font-size: 1.25rem;
  }

  .era-card-body {
    font-size: 0.9rem;
  }
}

@media (max-width: 480px) {
  .timeline {
    padding: 1rem 0;
  }

  .timeline-header {
    padding: 0.75rem;
  }

  .timeline-header h1 {
    font-size: 1.1rem;
  }

  .timeline-zoom-controls {
    display: none;
  }

  .timeline-minimap {
    width: 100%;
    height: 60px;
    right: auto;
    left: 0;
    bottom: 0;
    top: auto;
    transform: none;
    border-radius: 0;
    padding: 0.5rem;
  }

  .era-card {
    width: 95vw;
    padding: 1rem;
    margin: 0 auto;
  }

  .era-card-title {
    font-size: 1.1rem;
  }

  .timeline-badge {
    font-size: 0.65rem;
  }
}

/* =========================================
   ACCESSIBILITY
   ========================================= */

.timeline-marker:focus,
.era-card:focus,
.zoom-button:focus,
.minimap-dot:focus {
  outline: 2px solid var(--timeline-cyan);
  outline-offset: 2px;
}

/* Reduced motion preferences */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .timeline-marker {
    animation: none;
  }

  .timeline {
    scroll-behavior: auto;
  }
}

/* High contrast mode support */
@media (prefers-contrast: more) {
  .timeline-border {
    border-color: var(--timeline-primary);
  }

  .era-card {
    border-width: 2px;
  }
}

/* Dark mode (default) is already applied */
@media (prefers-color-scheme: light) {
  :root {
    --timeline-dark-bg: #f5f5f5;
    --timeline-card-bg: #ffffff;
    --timeline-text-primary: #1a1a1a;
    --timeline-text-secondary: #666;
    --timeline-border: #e0e0e0;
  }
}