/* ============================================
    timeline.css — Scroll-Spy Timeline Experience
    ============================================ */

.timeline-page {
   overflow-x: clip;
}

/* ---- Hero ---- */
.timeline-hero {
   position: relative;
   padding: 8rem 0 4.5rem;
   background:
      radial-gradient(circle at 15% 20%, rgba(200, 182, 255, 0.25), transparent 32%),
      radial-gradient(circle at 82% 12%, rgba(255, 214, 255, 0.20), transparent 28%),
      linear-gradient(180deg, rgba(255, 255, 255, 0.1), transparent),
      var(--color-bg);
}

.timeline-hero__inner {
   position: relative;
   z-index: 1;
}

.timeline-hero__glow {
   position: absolute;
   border-radius: 999px;
   filter: blur(60px);
   opacity: 0.55;
   pointer-events: none;
}

.timeline-hero__glow--one {
   top: 5rem;
   left: -4rem;
   width: 14rem;
   height: 14rem;
   background: rgba(184, 192, 255, 0.3);
}

.timeline-hero__glow--two {
   top: 2rem;
   right: -3rem;
   width: 16rem;
   height: 16rem;
   background: rgba(255, 214, 255, 0.22);
}

.timeline-eyebrow {
   display: inline-flex;
   align-items: center;
   gap: 0.55rem;
   margin-bottom: 0.9rem;
   font-family: 'Cinzel', serif;
   font-size: 0.82rem;
   letter-spacing: 0.16em;
   text-transform: uppercase;
   color: var(--color-primary);
}

.timeline-eyebrow::before {
   content: '';
   width: 2.5rem;
   height: 1px;
   background: currentColor;
   opacity: 0.55;
}

.timeline-hero h1 {
   max-width: none;
   font-size: clamp(3rem, 8vw, 5.6rem);
   line-height: 0.95;
   margin-bottom: 1.25rem;
}

.timeline-hero__lead {
   max-width: 46rem;
   color: var(--color-text-muted);
   font-size: 1.05rem;
}

/* ---- Main Grid Layout ---- */
.timeline-layout-section {
   padding: 2rem 0 6rem;
   background-color: var(--color-bg);
}

.timeline-layout-grid {
   display: grid;
   grid-template-columns: 130px 1fr;
   gap: 1.5rem;
   align-items: start;
}

/* ---- Sticky Left Sidebar (PC) ---- */
.timeline-sidebar {
   position: sticky;
   top: 100px;
   max-height: calc(100vh - 140px);
   overflow-y: auto;
   overflow-x: hidden;
   scrollbar-width: none; /* Hide scrollbars */
   padding-right: 0.5rem;
   z-index: 10;
}

.timeline-sidebar::-webkit-scrollbar {
   display: none;
}

.timeline-track-wrap {
   position: relative;
   padding: 1.5rem 0;
}

.timeline-track-line {
   position: absolute;
   left: 20px; /* Centered exactly on the 40px dot-wrap */
   transform: translateX(-50%);
   top: 0;
   bottom: 0;
   width: 2px;
   background: linear-gradient(to bottom, var(--color-border), var(--color-primary), var(--color-border));
   z-index: 1;
}

.timeline-track-nodes {
   position: relative;
   display: flex;
   flex-direction: column;
   gap: 2rem;
   z-index: 2;
   padding-left: 0;
}

.timeline-node {
   display: flex;
   flex-direction: row;
   align-items: center;
   background: none;
   border: none;
   cursor: pointer;
   padding: 0.5rem 0;
   outline: none;
   transition: transform 0.25s ease;
   width: 100%;
   text-align: left;
}

.timeline-node__dot-wrap {
   width: 40px;
   height: 40px;
   display: flex;
   justify-content: center;
   align-items: center;
   flex-shrink: 0;
}

.timeline-node__dot {
   width: 14px;
   height: 14px;
   border-radius: 50%;
   background: var(--color-bg);
   border: 2px solid var(--color-border);
   box-shadow: var(--shadow-sm);
   transition: background 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
   margin-bottom: 0;
   flex-shrink: 0;
}

.timeline-node__label {
   font-family: 'Cinzel', serif;
   font-size: 0.88rem;
   font-weight: 600;
   color: var(--color-text-muted);
   transition: color 0.25s ease, font-weight 0.25s ease;
   white-space: nowrap;
}

/* Active node states */
.timeline-node:hover .timeline-node__dot {
   border-color: var(--color-primary);
   transform: scale(1.15);
}

.timeline-node.is-active .timeline-node__dot {
   background: var(--color-primary);
   border-color: var(--color-primary);
   box-shadow: 0 0 0 4px color-mix(in srgb, var(--color-primary) 25%, transparent);
   transform: scale(1.2);
}

.timeline-node.is-active .timeline-node__label {
   color: var(--color-primary);
   font-weight: 700;
}

/* ---- Timeline Content Stack (Right) ---- */
.timeline-scroll-content {
   display: flex;
   flex-direction: column;
   gap: 5.5rem;
}

.timeline-year-section {
   scroll-margin-top: 100px; /* Offset smooth scroll targets below header */
   transition: opacity 0.6s ease;
   opacity: 0.35; /* De-emphasized when inactive */
}

.timeline-year-section.is-active-section {
   opacity: 1;
}

/* Year Header Block (Heading first, then Badge, Centered) */
.timeline-year-header {
   display: flex;
   flex-direction: column;
   align-items: center;
   text-align: center;
   margin-bottom: 1.5rem;
   transform: translateY(15px);
   transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.timeline-year-section.is-active-section .timeline-year-header {
   transform: translateY(0);
}

.timeline-year-heading {
   font-family: 'Cormorant Garamond', serif;
   font-size: clamp(2rem, 3.2vw, 2.75rem);
   font-weight: 700;
   color: var(--color-heading);
   line-height: 1.2;
   margin-bottom: 0.75rem;
   max-width: 44rem;
}

.timeline-badge-pill {
   display: inline-flex;
   align-items: center;
   background: linear-gradient(135deg, rgba(157, 140, 223, 0.12) 0%, rgba(123, 132, 204, 0.12) 100%);
   border: 1px solid color-mix(in srgb, var(--color-primary) 30%, transparent);
   color: var(--color-primary);
   padding: 0.35rem 0.95rem;
   font-family: 'Cinzel', serif;
   font-size: 0.78rem;
   letter-spacing: 0.12em;
   text-transform: uppercase;
   border-radius: 99px;
   font-weight: 600;
   box-shadow: 0 2px 8px rgba(157, 140, 223, 0.04);
}

/* Gallery Column & Grid Layout */
.timeline-year-gallery {
   display: flex;
   flex-direction: column;
   margin-top: 1rem;
}

.timeline-gallery-grid {
   display: grid;
   grid-template-columns: repeat(4, 1fr);
   gap: 0.5rem;
   align-items: start;
}

.timeline-gallery-item {
   position: relative;
   border-radius: 1.25rem;
   overflow: hidden;
   border: 1px solid var(--color-border);
   background-color: var(--color-bg-alt);
   box-shadow: var(--shadow-sm);
   cursor: zoom-in;
   
   /* Initial hidden state (disappeared) */
   opacity: 0;
   transform: translateY(30px) scale(0.92);
   transition: 
      transform 0.6s cubic-bezier(0.34, 1.56, 0.64, 1), 
      opacity 0.6s ease, 
      box-shadow var(--transition);
}

/* Appeared state on viewport scroll entry */
.timeline-gallery-item.is-visible {
   opacity: 1;
   transform: translateY(0) scale(1);
}

/* Staggered delay for cascading item entries */
.timeline-gallery-item:nth-child(1) { transition-delay: 0.05s; }
.timeline-gallery-item:nth-child(2) { transition-delay: 0.12s; }
.timeline-gallery-item:nth-child(3) { transition-delay: 0.19s; }
.timeline-gallery-item:nth-child(4) { transition-delay: 0.26s; }
.timeline-gallery-item:nth-child(n+5) { transition-delay: 0.33s; }

.timeline-gallery-item:hover {
   transform: scale(1.03) !important; /* Override reveal scale slightly for hover feedback */
   box-shadow: var(--shadow-md);
}

.timeline-gallery-item img {
   width: 100%;
   height: auto;
   display: block;
   opacity: 0;
   transition: transform 0.5s ease, opacity 0.4s ease;
}

/* Reveal loaded lazy image */
.timeline-gallery-item.is-image-loaded img {
   opacity: 1;
}

.timeline-gallery-item:hover img {
   transform: scale(1.05);
}

/* Loading Spinner Overlay */
.timeline-gallery-item__loader {
   position: absolute;
   inset: 0;
   display: flex;
   align-items: center;
   justify-content: center;
   background-color: var(--color-bg-alt);
   transition: opacity 0.4s ease;
   z-index: 2;
}

.loader-spinner {
   width: 28px;
   height: 28px;
   border: 3px solid rgba(157, 140, 223, 0.15);
   border-top-color: var(--color-primary);
   border-radius: 50%;
   animation: spin 1s linear infinite;
}

@keyframes spin {
   to { transform: rotate(360deg); }
}

/* Hide loader when image is loaded */
.timeline-gallery-item.is-image-loaded .timeline-gallery-item__loader {
   opacity: 0;
   pointer-events: none;
}

.timeline-gallery-item__overlay {
   position: absolute;
   inset: 0;
   background: linear-gradient(to top, rgba(0, 0, 0, 0.72) 0%, transparent 70%);
   display: flex;
   align-items: flex-end;
   padding: 1.25rem;
   opacity: 0;
   transition: opacity 0.3s ease;
   pointer-events: none;
}

.timeline-gallery-item:hover .timeline-gallery-item__overlay {
   opacity: 1;
}

.timeline-gallery-item__overlay p {
   color: #fff;
   font-size: 0.82rem;
   line-height: 1.4;
   margin: 0;
}

/* Aspect ratio values are ignored in favor of uniform squares */

.timeline-no-media {
   color: var(--color-text-muted);
   font-size: 0.95rem;
}

/* ---- Lightbox Modal ---- */
.timeline-lightbox {
   position: fixed;
   inset: 0;
   z-index: 1500;
   display: none;
   align-items: center;
   justify-content: center;
   padding: 1.5rem;
}

.timeline-lightbox.is-open {
   display: flex;
}

.timeline-lightbox__backdrop {
   position: absolute;
   inset: 0;
   background: rgba(0, 0, 0, 0.88);
   backdrop-filter: blur(8px);
   cursor: zoom-out;
}

.timeline-lightbox__dialog {
   position: relative;
   z-index: 2;
   max-width: 900px;
   width: 100%;
   display: flex;
   flex-direction: column;
   border-radius: 1.5rem;
   overflow: hidden;
   background-color: #000;
   box-shadow: 0 20px 50px rgba(0,0,0,0.5);
   animation: scaleUp 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.timeline-lightbox__close {
   position: absolute;
   top: 1rem;
   right: 1rem;
   width: 2.75rem;
   height: 2.75rem;
   border-radius: 50%;
   border: none;
   background: rgba(255, 255, 255, 0.15);
   color: #fff;
   font-size: 1.2rem;
   cursor: pointer;
   display: grid;
   place-items: center;
   transition: background 0.2s ease, transform 0.2s ease;
   z-index: 10;
}

.timeline-lightbox__close:hover {
   background: rgba(255, 255, 255, 0.25);
   transform: scale(1.05);
}

.timeline-lightbox__media-wrap {
   width: 100%;
   max-height: 70vh;
   background-color: #000;
   display: flex;
   align-items: center;
   justify-content: center;
   overflow: hidden;
}

.timeline-lightbox__media-wrap img {
   max-width: 100%;
   max-height: 70vh;
   object-fit: contain;
}

.timeline-lightbox__caption-bar {
   background-color: rgba(20, 20, 20, 0.95);
   padding: 1.5rem;
   border-top: 1px solid rgba(255,255,255,0.08);
}

.timeline-lightbox__caption-bar p {
   color: rgba(255, 255, 255, 0.9);
   font-size: 0.95rem;
   line-height: 1.5;
   margin: 0;
   text-align: center;
}

/* ---- Animations ---- */
@keyframes fadeIn {
   from { opacity: 0; transform: translateY(12px); }
   to { opacity: 1; transform: translateY(0); }
}

@keyframes scaleUp {
   from { opacity: 0; transform: scale(0.92); }
   to { opacity: 1; transform: scale(1); }
}

/* ---- Responsive (Mobile/Tablet) ---- */
@media (max-width: 900px) {
   .timeline-layout-grid {
      grid-template-columns: 1fr;
      gap: 2rem;
   }

   /* Transform left sidebar into sticky top horizontal track */
   .timeline-sidebar {
      position: sticky;
      top: 70px; /* immediately below navbar */
      max-height: none;
      overflow-y: visible;
      background-color: var(--color-bg);
      border-bottom: 1px solid var(--color-border);
      margin: 0 -1.5rem 1rem;
      padding: 1rem 1.5rem;
      z-index: 100;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
   }

   .timeline-track-wrap {
      padding: 0;
   }

   .timeline-track-line {
      position: absolute;
      top: 20px; /* Centered exactly on the 40px dot-wrap vertically */
      left: 0;
      right: 0;
      bottom: unset;
      height: 2px;
      width: 100%;
      background: linear-gradient(to right, var(--color-border), var(--color-primary), var(--color-border));
      transform: translateY(-50%);
   }

   .timeline-track-nodes {
      flex-direction: row;
      overflow-x: auto;
      gap: 1.5rem;
      justify-content: flex-start;
      padding: 0 1rem;
      scrollbar-width: none;
   }

   .timeline-track-nodes::-webkit-scrollbar {
      display: none;
   }

   .timeline-node {
      flex-direction: column;
      align-items: center;
      gap: 0.4rem;
      width: auto;
      padding: 0 0.2rem;
   }

   .timeline-year-grid {
      grid-template-columns: 1fr;
      gap: 2.2rem;
   }

   .timeline-year-section {
      scroll-margin-top: 170px; /* Extra offset to account for sticky horizontal track + navbar */
      padding-bottom: 3.5rem;
      border-bottom: 1px solid var(--color-border);
   }

   .timeline-year-section:last-child {
      border-bottom: none;
   }

   .timeline-gallery-grid {
      grid-template-columns: repeat(3, 1fr);
   }
}

@media (max-width: 600px) {
   .timeline-hero {
      padding-top: 7rem;
   }

   .timeline-year-heading {
      font-size: 1.9rem;
   }

   .timeline-gallery-grid {
      grid-template-columns: repeat(2, 1fr);
   }

   /* Cleaned legacy masonry grid classes */

   .timeline-lightbox {
      padding: 0.8rem;
   }
   
   .timeline-lightbox__media-wrap {
      max-height: 60vh;
   }
   
   .timeline-lightbox__media-wrap img {
      max-height: 60vh;
   }

   .timeline-lightbox__caption-bar {
      padding: 1.25rem 1rem;
   }
}