/* ── Reset & Base ─────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0d0d12;
  --surface:   #18182a;
  --surface-2: #20203a;
  --border:    rgba(255,255,255,0.09);
  --accent:    #7c6ff7;
  --accent-2:  #a78bfa;
  --text:      #e2e2f0;
  --muted:     rgba(226,226,240,0.60);
  --radius:    14px;
  --nav-size:  48px;
}

html, body {
  height: 100%;
}

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  /* Subtle noise-free dark base — no edge halos */
}

/* ─────────────────────────────────────────────────────────────── */
/*  GALLERY PAGE                                                   */
/* ─────────────────────────────────────────────────────────────── */
body.page-gallery {
  display: flex;
  flex-direction: column;
  align-items: center;
  /* Single centered glow at the very top of the document */
  background:
    radial-gradient(ellipse 80% 40% at 50% -5%, rgba(124,111,247,0.14) 0%, transparent 65%),
    var(--bg);
}

/* Hero */
#hero {
  position: relative;
  width: 100%;
  text-align: center;
  padding: 72px 20px 52px;
  overflow: hidden;
}

/* Subtle glow confined to the hero area only */
#hero-glow {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 55% 100% at 50% 0%, rgba(124,111,247,0.13) 0%, transparent 70%);
  pointer-events: none;
}

#hero-title {
  font-size: clamp(1.9rem, 4vw, 2.9rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(140deg, #fff 30%, var(--accent-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 10px;
}

#hero-sub {
  font-size: 0.95rem;
  color: var(--muted);
}

/* Year Filter Tabs */
#year-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
  padding: 0 24px 32px;
  max-width: 1100px;
  width: 100%;
}

.year-tab {
  padding: 6px 20px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
  font-family: 'Inter', sans-serif;
  font-size: 0.82rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, color 0.2s, border-color 0.2s, box-shadow 0.2s;
}
.year-tab:hover {
  color: var(--text);
  border-color: var(--accent);
  background: rgba(124,111,247,0.08);
}
.year-tab.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  box-shadow: 0 4px 18px rgba(124,111,247,0.30);
}

/* Gallery Grid */
#gallery-grid {
  width: 100%;
  max-width: 1100px;
  padding: 0 24px 80px;
  display: flex;
  flex-direction: column;
  gap: 44px;
}

/* Year Section */
.year-section {}

.year-heading {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(195px, 1fr));
  gap: 20px;
}

/* PDF Card */
.pdf-card {
  text-decoration: none;
  color: inherit;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
  animation: fadeUp 0.4s ease both;
  cursor: pointer;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

.pdf-card:hover {
  transform: translateY(-5px);
  border-color: var(--accent);
  box-shadow: 0 12px 40px rgba(124,111,247,0.20), 0 2px 8px rgba(0,0,0,0.55);
}

/* Thumbnail */
.thumb-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 3 / 4;
  background: var(--surface-2);
  overflow: hidden;
}

.thumb-skeleton {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, var(--surface-2) 25%, #28284a 50%, var(--surface-2) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.4s infinite;
}
@keyframes shimmer {
  from { background-position: 200% 0; }
  to   { background-position: -200% 0; }
}

.thumb-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.thumb-canvas.loaded { opacity: 1; }

.thumb-wrap.thumb-error::after {
  content: '📄';
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
}

/* Card Info */
.card-info {
  padding: 14px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 5px;
  flex: 1;
}

.card-title {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.35;
}

.card-desc {
  font-size: 0.77rem;
  color: var(--muted);
  line-height: 1.5;
  flex: 1;
}

.card-cta {
  font-size: 0.77rem;
  font-weight: 600;
  color: var(--accent-2);
  margin-top: 6px;
  transition: letter-spacing 0.2s;
}
.pdf-card:hover .card-cta { letter-spacing: 0.04em; }


/* ─────────────────────────────────────────────────────────────── */
/*  VIEWER PAGE                                                    */
/* ─────────────────────────────────────────────────────────────── */
body.page-viewer {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
  overflow: hidden;
  /* Single centred glow — contained, does NOT bleed to edges */
  background:
    radial-gradient(ellipse 60% 55% at 50% 55%, rgba(124,111,247,0.10) 0%, transparent 65%),
    var(--bg);
}

/* Loader */
#loader {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: var(--bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  transition: opacity 0.4s ease;
}
#loader.hidden { opacity: 0; pointer-events: none; }

.spinner {
  width: 46px;
  height: 46px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

#loader-text {
  font-size: 0.84rem;
  color: var(--muted);
  letter-spacing: 0.03em;
}

#progress-wrap {
  width: 220px;
  height: 4px;
  background: var(--surface-2);
  border-radius: 4px;
  overflow: hidden;
}
#progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  border-radius: 4px;
  transition: width 0.15s ease;
}
#progress-pct {
  font-size: 0.73rem;
  color: var(--muted);
  letter-spacing: 0.04em;
  margin-top: -8px;
}

/* Viewer Wrap — column layout fills full viewport */
#viewer-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  gap: 0;
  width: 100%;
  height: 100vh;
  padding: 16px;
  overflow: hidden;
}

/* Top Bar */
#top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 980px;
  flex-shrink: 0;
  padding: 0 2px;
}

#back-btn {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 6px 16px;
  border-radius: 20px;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}
#back-btn:hover {
  color: var(--accent-2);
  border-color: var(--accent);
  background: rgba(124,111,247,0.08);
}

#pdf-title {
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: capitalize;
  max-width: 40%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  text-align: center;
}

#page-counter {
  font-size: 0.82rem;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 5px 14px;
  border-radius: 20px;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

/* Stage — fills the middle space, buttons hug the flipbook */
#stage {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex: 1;
  width: 100%;
  overflow: hidden;
}

/* Inner stage constrains the flipbook + button group */
#stage-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  max-width: 100%;
}

/* Nav Buttons */
.nav-btn {
  flex-shrink: 0;
  width: var(--nav-size);
  height: var(--nav-size);
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  font-size: 1.7rem;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, border-color 0.2s, transform 0.15s, box-shadow 0.2s;
  box-shadow: 0 2px 12px rgba(0,0,0,0.4);
  user-select: none;
}
.nav-btn:hover {
  background: var(--accent);
  border-color: var(--accent);
  transform: scale(1.08);
  box-shadow: 0 4px 20px rgba(124,111,247,0.38);
}
.nav-btn:active { transform: scale(0.96); }
.nav-btn:disabled { opacity: 0.22; cursor: not-allowed; transform: none; box-shadow: none; }

/* Flipbook Shell */
#flipbook {
  cursor: pointer;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow:
    0 0 0 1px var(--border),
    0 28px 70px rgba(0,0,0,0.75),
    0 0 50px rgba(124,111,247,0.07);
  background: #fff;
  flex-shrink: 0;
}

/* Pages */
.page {
  background: #fff;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Shimmer placeholder shown for pages not yet rendered */
.page-placeholder {
  background: linear-gradient(90deg, #e8e8e8 25%, #d4d4d4 50%, #e8e8e8 75%);
  background-size: 200% 100%;
  animation: shimmer-light 1.4s infinite;
}
@keyframes shimmer-light {
  from { background-position: 200% 0; }
  to   { background-position: -200% 0; }
}


.page canvas {
  display: block;
  pointer-events: none;
  /* NO forced width/height — JS sets exact pixel dimensions per page */
}

/* Bottom Hint */
#bottom-bar {
  text-align: center;
  flex-shrink: 0;
}
#hint {
  font-size: 0.73rem;
  color: var(--muted);
  letter-spacing: 0.03em;
}