/* ===================================================================
   Flipbook KKNT 2025 Modern Stylesheet
   =================================================================== */

:root {
  --bg-primary: #12151b;
  --bg-secondary: #1a1e27;
  --bg-tertiary: #242a38;
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --accent-color: #3b82f6;
  --accent-hover: #2563eb;
  --border-color: rgba(255, 255, 255, 0.08);
  --glass-bg: rgba(26, 30, 39, 0.88);
  --glass-border: rgba(255, 255, 255, 0.12);
  --shadow-lg: 0 20px 40px -15px rgba(0, 0, 0, 0.6);
  --font-family: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: var(--bg-primary);
  font-family: var(--font-family);
  color: var(--text-main);
  user-select: none;
}

/* Base App Layout */
.app-container {
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 100%;
  position: relative;
  background: radial-gradient(circle at center, #1f2533 0%, #0d1017 100%);
}

/* ===================================================================
   Top Navigation Bar
   =================================================================== */
.top-bar {
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.25rem;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 40;
  flex-shrink: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand-icon {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.doc-title {
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #fff;
  line-height: 1.2;
}

.doc-subtitle {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 400;
}

.top-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Buttons */
.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  height: 36px;
  padding: 0 0.75rem;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.18s ease;
}

.icon-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateY(-1px);
}

.icon-btn:active {
  transform: translateY(0);
}

.download-btn {
  background: rgba(59, 130, 246, 0.15);
  border-color: rgba(59, 130, 246, 0.3);
  color: #60a5fa;
}

.download-btn:hover {
  background: rgba(59, 130, 246, 0.25);
  color: #93c5fd;
  border-color: rgba(59, 130, 246, 0.5);
}

/* ===================================================================
   Main Viewport & Flipbook Container
   =================================================================== */
.flipbook-viewport {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: 1rem;
}

.zoom-container {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  transform-origin: center center;
  transition: transform 0.2s cubic-bezier(0.25, 1, 0.5, 1);
  will-change: transform;
}

.flipbook {
  box-shadow: var(--shadow-lg);
  margin: auto;
  position: relative;
  max-height: calc(100vh - 140px);
  max-width: min(calc((100vh - 140px) * 1.4075), calc(100vw - 120px));
  width: 100%;
}

@media (max-width: 768px) {
  .flipbook {
    max-height: calc(100vh - 130px);
    max-width: min(calc((100vh - 130px) * 0.70375), calc(100vw - 32px));
    width: 100%;
  }
}

/* Page Styling */
.page {
  background-color: #ffffff;
  overflow: hidden;
  box-shadow: inset 0 0 30px rgba(0, 0, 0, 0.06);
}

.page-content {
  width: 100%;
  height: 100%;
  position: relative;
  background-color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-content img {
  width: 100%;
  height: 100%;
  object-fit: fill;
  display: block;
  pointer-events: none;
}

/* Hard Cover Styling */
.page-cover {
  background-color: #f8fafc;
}

.hard-cover-spine {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 30px;
  pointer-events: none;
  z-index: 2;
}

.page-cover-top .hard-cover-spine {
  right: 0;
  background: linear-gradient(to left, rgba(0, 0, 0, 0.22) 0%, rgba(0, 0, 0, 0.05) 50%, rgba(0, 0, 0, 0) 100%);
}

.page-cover-bottom .hard-cover-spine {
  left: 0;
  background: linear-gradient(to right, rgba(0, 0, 0, 0.22) 0%, rgba(0, 0, 0, 0.05) 50%, rgba(0, 0, 0, 0) 100%);
}

/* Quick Nav Side Buttons */
.side-nav-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 46px;
  height: 54px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(20, 24, 33, 0.7);
  backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  color: #fff;
  cursor: pointer;
  z-index: 30;
  border-radius: 12px;
  transition: all 0.2s ease;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
}

.side-nav-btn.prev {
  left: 1.25rem;
}

.side-nav-btn.next {
  right: 1.25rem;
}

.side-nav-btn:hover {
  background: rgba(59, 130, 246, 0.85);
  transform: translateY(-50%) scale(1.06);
  border-color: rgba(59, 130, 246, 0.6);
}

.side-nav-btn:active {
  transform: translateY(-50%) scale(0.96);
}

/* ===================================================================
   Bottom Navigation Bar
   =================================================================== */
.bottom-bar {
  height: 54px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0 1rem;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid var(--glass-border);
  z-index: 40;
  flex-shrink: 0;
}

.nav-controls, .zoom-controls {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.bar-btn {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.15s ease;
}

.bar-btn:hover {
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.22);
}

.bar-btn:active {
  transform: scale(0.94);
}

.text-btn {
  width: auto;
  padding: 0 0.6rem;
  font-size: 0.78rem;
  font-weight: 600;
}

.bar-separator {
  width: 1px;
  height: 22px;
  background-color: var(--glass-border);
  margin: 0 0.5rem;
}

/* Page Indicator & Direct Input */
.page-indicator-wrap {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(0, 0, 0, 0.3);
  padding: 0.2rem 0.6rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  font-size: 0.85rem;
  font-weight: 500;
}

#pageInput {
  width: 40px;
  height: 26px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 4px;
  color: #fff;
  text-align: center;
  font-weight: 600;
  font-family: inherit;
  font-size: 0.85rem;
  outline: none;
}

#pageInput:focus {
  border-color: var(--accent-color);
  background: rgba(255, 255, 255, 0.15);
}

/* Remove number spin buttons */
#pageInput::-webkit-outer-spin-button,
#pageInput::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.page-divider {
  color: var(--text-muted);
}

#pageTotal {
  color: var(--text-muted);
}

.zoom-level {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  min-width: 44px;
  text-align: center;
}

/* ===================================================================
   Thumbnails Drawer (Sidebar)
   =================================================================== */
.thumbnail-drawer {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 290px;
  background: #181d26;
  border-right: 1px solid var(--glass-border);
  z-index: 60;
  display: flex;
  flex-direction: column;
  transform: translateX(-100%);
  transition: transform 0.28s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 10px 0 30px rgba(0, 0, 0, 0.5);
}

.thumbnail-drawer.open {
  transform: translateX(0);
}

.drawer-header {
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1rem;
  border-bottom: 1px solid var(--border-color);
  flex-shrink: 0;
}

.drawer-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  font-weight: 600;
}

.icon-btn-close {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.25rem;
  border-radius: 6px;
  transition: all 0.15s;
}

.icon-btn-close:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.1);
}

.drawer-content {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.85rem;
}

/* Custom Scrollbar for Drawer */
.drawer-content::-webkit-scrollbar {
  width: 6px;
}
.drawer-content::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: 4px;
}

.thumb-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
  cursor: pointer;
  padding: 0.4rem;
  border-radius: 8px;
  border: 1px solid transparent;
  transition: all 0.18s ease;
  background: rgba(255, 255, 255, 0.03);
}

.thumb-item:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
}

.thumb-item.active {
  border-color: var(--accent-color);
  background: rgba(59, 130, 246, 0.15);
  box-shadow: 0 0 0 1px var(--accent-color);
}

.thumb-item img {
  width: 100%;
  aspect-ratio: 1 / 1.42;
  object-fit: cover;
  border-radius: 4px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.thumb-item span {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
}

.thumb-item.active span {
  color: #93c5fd;
  font-weight: 600;
}

/* Drawer Overlay Backdrop */
.drawer-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(2px);
  z-index: 50;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.drawer-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

/* Toast */
.toast {
  position: absolute;
  bottom: 70px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: rgba(24, 29, 38, 0.95);
  border: 1px solid var(--glass-border);
  color: #fff;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  font-size: 0.8rem;
  box-shadow: 0 8px 24px rgba(0,0,0,0.5);
  opacity: 0;
  pointer-events: none;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 100;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Utility Helpers */
.hidden {
  display: none !important;
}

/* ===================================================================
   Responsive Media Queries
   =================================================================== */
@media (max-width: 768px) {
  .top-bar {
    padding: 0 0.75rem;
  }
  .btn-label {
    display: none;
  }
  .doc-subtitle {
    display: none;
  }
  .side-nav-btn {
    display: none; /* Rely on touch swiping and bottom bar on mobile */
  }
  .zoom-controls {
    display: none; /* Zoom by pinch gesture on mobile */
  }
  .bar-separator {
    display: none;
  }
  .thumbnail-drawer {
    width: 260px;
  }
}