/**
 * SMARTDOCIFY - MERGE PDF STYLESHEET (REPAIRED & RESPONSIVE)
 * Token-driven design system with strict container centering,
 * responsive visual sizing, horizontal breadcrumbs, and full light/dark theme parity.
 */

:root {
  --font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  
  /* Foundation Tokens - Light Theme */
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-surface-alt: #f1f5f9;
  --bg-card: #ffffff;
  
  --border-subtle: #e2e8f0;
  --border-medium: #cbd5e1;
  --border-hover: #94a3b8;
  --border-color: #e2e8f0;
  
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-light: #94a3b8;
  
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: rgba(37, 99, 235, 0.08);
  --primary-glow: rgba(37, 99, 235, 0.25);
  
  --success: #10b981;
  --success-hover: #059669;
  --success-light: rgba(16, 185, 129, 0.1);
  
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --danger-light: rgba(239, 68, 68, 0.1);
  
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.06), 0 1px 2px 0 rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-full: 9999px;
  
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

[data-theme="dark"] {
  /* Foundation Tokens - Dark Theme with Clear Contrast */
  --bg-base: #0f172a;
  --bg-surface: #1e293b;
  --bg-surface-alt: #172338;
  --bg-card: #1e293b;
  
  --border-subtle: #2d3b55;
  --border-medium: #3b4c6b;
  --border-hover: #506690;
  --border-color: #2d3b55;
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-light: #64748b;
  
  --primary: #3b82f6;
  --primary-hover: #60a5fa;
  --primary-light: rgba(59, 130, 246, 0.15);
  --primary-glow: rgba(59, 130, 246, 0.35);
  
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.35);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 10px 20px -3px rgba(0, 0, 0, 0.55);
}

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

html {
  font-family: var(--font-family);
  background-color: var(--bg-base);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-base);
  color: var(--text-main);
  overflow-x: hidden;
  font-size: 16px;
}

/* Master Centered Page Container */
.container,
.main-container {
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding-inline: clamp(16px, 3vw, 24px);
  box-sizing: border-box;
}

/* ==========================================================================
   HEADER & NAVIGATION
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: clamp(16px, 3vw, 24px);
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-main);
}

.logo-icon-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-svg {
  width: 32px;
  height: 32px;
  display: block;
}

.logo-text {
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--primary) 0%, #7c3aed 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.desktop-nav .nav-list {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 0.5rem;
}

.nav-link {
  display: inline-block;
  padding: 0.5rem 0.85rem;
  font-size: 0.925rem;
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-link:hover {
  color: var(--primary);
  background-color: var(--primary-light);
}

.nav-link.active {
  color: var(--primary);
  background-color: var(--primary-light);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.action-btn:hover {
  color: var(--text-main);
  border-color: var(--border-medium);
  background-color: var(--bg-surface-alt);
}

.action-btn svg {
  width: 20px;
  height: 20px;
}

[data-theme="dark"] .icon-moon,
[data-theme="light"] .icon-sun {
  display: none;
}

[data-theme="dark"] .icon-sun,
[data-theme="light"] .icon-moon {
  display: block;
}

.menu-toggle {
  display: none;
}

.hamburger-box {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hamburger-line {
  width: 18px;
  height: 2px;
  background-color: currentColor;
  border-radius: 1px;
}

/* Mobile Nav Drawer */
.mobile-nav-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 199;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}

.mobile-nav-backdrop.open {
  opacity: 1;
  visibility: visible;
}

.mobile-nav-drawer {
  position: fixed;
  top: 0;
  right: -290px;
  width: 280px;
  height: 100%;
  background-color: var(--bg-surface);
  z-index: 200;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  visibility: hidden;
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), visibility 0.3s ease;
}

.mobile-nav-drawer.open {
  visibility: visible;
  transform: translateX(-290px);
}

.mobile-drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

.mobile-nav-body {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  flex-grow: 1;
}

.mobile-nav-list {
  list-style: none;
}

.mobile-nav-link {
  display: block;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
  background-color: var(--primary-light);
  color: var(--primary);
}

/* ==========================================================================
   BREADCRUMB (CLEAN HORIZONTAL RESPONSIVE UI)
   ========================================================================== */
.breadcrumb-nav {
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding: 1rem clamp(16px, 3vw, 24px) 0.5rem clamp(16px, 3vw, 24px);
  box-sizing: border-box;
}

.breadcrumb-trail {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  list-style: none !important;
  margin: 0;
  padding: 0;
}

.breadcrumb-item {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
  display: inline-flex;
  align-items: center;
}

.breadcrumb-item:hover {
  color: var(--primary);
}

.breadcrumb-item.active {
  color: var(--text-main);
  font-weight: 600;
}

.breadcrumb-separator {
  color: var(--text-light);
  font-size: 0.85rem;
  user-select: none;
}

/* ==========================================================================
   HERO SECTION (CLEAN, BALANCED, APPROPRIATELY SIZED)
   ========================================================================== */
.tool-hero-section {
  text-align: center;
  padding: 1rem 0 1.5rem 0;
  width: 100%;
}

.hero-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

/* Hero Visual Icon Illustration (Strictly bounded) */
.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 0.85rem auto;
  max-width: 320px;
  max-height: 180px;
}

.hero-visual-svg {
  width: 68px;
  height: 68px;
  display: block;
}

.tool-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.3rem 0.85rem;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  background-color: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-full);
  margin-bottom: 0.75rem;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--primary);
}

.tool-title {
  font-size: clamp(2rem, 3.8vw, 2.6rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.025em;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.tool-subtitle {
  font-size: clamp(0.95rem, 1.6vw, 1.1rem);
  color: var(--text-muted);
  max-width: 620px;
  margin: 0 auto 1rem auto;
  line-height: 1.5;
}

.privacy-trust-note {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.825rem;
  font-weight: 600;
  color: var(--text-muted);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  padding: 0.35rem 0.95rem;
  border-radius: var(--radius-full);
}

.privacy-trust-note svg {
  width: 15px;
  height: 15px;
  color: var(--success);
  flex-shrink: 0;
}

/* ==========================================================================
   TOOL WORKSPACE (PROMINENT, NEAR TOP OF PAGE)
   ========================================================================== */
.workspace-wrapper {
  margin: 0 auto 3rem auto;
  width: 100%;
  max-width: 960px;
  box-sizing: border-box;
}

/* 1. Empty State: Upload Dropzone Card */
.upload-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: clamp(1.5rem, 4vw, 2.25rem);
  box-shadow: var(--shadow-md);
  text-align: center;
  transition: all var(--transition-normal);
}

.dropzone {
  border: 2px dashed var(--border-medium);
  border-radius: var(--radius-lg);
  padding: clamp(2rem, 5vw, 3rem) 1.5rem;
  background-color: var(--bg-surface-alt);
  cursor: pointer;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--primary);
  background-color: var(--primary-light);
  transform: scale(1.002);
}

.dropzone-icon-wrap {
  width: 58px;
  height: 58px;
  border-radius: var(--radius-full);
  background-color: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.15rem;
  transition: transform var(--transition-fast);
}

.dropzone:hover .dropzone-icon-wrap {
  transform: translateY(-2px);
}

.dropzone-icon-wrap svg {
  width: 30px;
  height: 30px;
}

.dropzone-title {
  font-size: clamp(1.2rem, 2.2vw, 1.45rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.35rem;
}

.dropzone-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 700;
  padding: 0.75rem 1.65rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.btn-primary {
  background-color: var(--primary);
  color: #ffffff;
  box-shadow: 0 2px 4px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.35);
  transform: translateY(-1px);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.btn-secondary {
  background-color: var(--bg-surface);
  color: var(--text-main);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--bg-surface-alt);
  border-color: var(--border-medium);
}

.btn-danger-ghost {
  background-color: transparent;
  color: var(--danger);
  border-color: transparent;
  padding: 0.4rem 0.8rem;
  font-size: 0.85rem;
}

.btn-danger-ghost:hover {
  background-color: var(--danger-light);
}

.dropzone-specs {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.5rem;
  font-size: 0.825rem;
  color: var(--text-light);
}

.spec-pill {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
}

/* Alert Boxes */
.alert-box {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  margin-top: 1.25rem;
  text-align: left;
}

.alert-danger {
  background-color: var(--danger-light);
  border: 1px solid rgba(239, 68, 68, 0.25);
  color: var(--danger);
}

.alert-danger svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  margin-top: 2px;
}

/* 2. Active State: File Ordering Workspace */
.active-workspace {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  padding: clamp(1.25rem, 3vw, 1.75rem);
  transition: all var(--transition-normal);
}

.workspace-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 1.25rem;
}

.workspace-stats {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.stat-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.75rem;
  background-color: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  font-size: 0.825rem;
  font-weight: 700;
  color: var(--text-muted);
}

.stat-badge svg {
  width: 14px;
  height: 14px;
  color: var(--primary);
}

.workspace-top-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

/* Reorder Hint Banner */
.reorder-hint {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  background-color: var(--primary-light);
  border: 1px solid rgba(37, 99, 235, 0.18);
  padding: 0.65rem 1rem;
  border-radius: var(--radius-md);
  margin-bottom: 1.25rem;
}

.reorder-hint svg {
  width: 16px;
  height: 16px;
  color: var(--primary);
  flex-shrink: 0;
}

/* PDF Card List */
.pdf-card-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  list-style: none;
  margin-bottom: 1.5rem;
  min-height: 100px;
}

.pdf-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 0.85rem 1.15rem;
  gap: 1rem;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
  cursor: grab;
  user-select: none;
}

.pdf-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.pdf-card.dragging {
  opacity: 0.45;
  cursor: grabbing;
  border-style: dashed;
  border-color: var(--primary);
}

.pdf-card.drag-over {
  border-color: var(--primary);
  background-color: var(--primary-light);
}

.card-left-group {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  min-width: 0;
  flex-grow: 1;
}

.drag-handle {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  cursor: grab;
  padding: 0.25rem;
  flex-shrink: 0;
}

.drag-handle svg {
  width: 18px;
  height: 18px;
}

.order-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: var(--radius-sm);
  background-color: var(--primary-light);
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
  flex-shrink: 0;
}

/* Live First-Page PDF Preview Thumbnail Box */
.pdf-preview-box {
  width: 64px;
  height: 84px;
  min-width: 64px;
  max-width: 64px;
  background-color: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.08);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

[data-theme="dark"] .pdf-preview-box {
  background-color: #1e293b;
  border-color: var(--border-color);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.35);
}

.pdf-card:hover .pdf-preview-box {
  border-color: var(--primary);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.15);
}

.pdf-preview-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
  display: block;
  pointer-events: none;
}

/* Skeleton Loading State */
.preview-skeleton {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(90deg, var(--bg-surface-alt) 25%, var(--border-color) 50%, var(--bg-surface-alt) 75%);
  background-size: 200% 100%;
  animation: previewShimmer 1.5s infinite linear;
}

@keyframes previewShimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.preview-spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(37, 99, 235, 0.2);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: previewSpin 0.75s infinite linear;
}

@keyframes previewSpin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Fallback Error State */
.preview-fallback {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  padding: 4px;
  background-color: var(--bg-surface-alt);
  color: var(--text-muted);
  text-align: center;
}

.preview-fallback svg {
  width: 20px;
  height: 20px;
  color: var(--text-light);
}

.preview-fallback-text {
  font-size: 0.65rem;
  font-weight: 600;
  line-height: 1.1;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.file-meta-col,
.file-info-group {
  min-width: 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.file-name {
  font-size: 0.925rem;
  font-weight: 600;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: block;
}

.file-specs,
.file-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.card-right-group,
.card-actions-group {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-shrink: 0;
}

.card-ctrl-btn,
.btn-card-ctrl {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-surface-alt);
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.card-ctrl-btn:hover:not(:disabled),
.btn-card-ctrl:hover:not(:disabled) {
  color: var(--primary);
  border-color: var(--primary);
  background-color: var(--primary-light);
}

.card-ctrl-btn.btn-remove:hover,
.btn-card-ctrl.remove-btn:hover {
  color: var(--danger);
  border-color: var(--danger);
  background-color: var(--danger-light);
}

.card-ctrl-btn:disabled,
.btn-card-ctrl:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.card-ctrl-btn svg,
.btn-card-ctrl svg {
  width: 15px;
  height: 15px;
}

.workspace-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border-color);
}

.filename-input-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.filename-input-group label {
  font-weight: 600;
  white-space: nowrap;
}

.filename-input-wrap {
  display: flex;
  align-items: center;
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  padding: 0 0.5rem;
  transition: border-color var(--transition-fast);
}

.filename-input-wrap:focus-within {
  border-color: var(--primary);
}

.filename-input {
  border: none;
  outline: none;
  background: transparent;
  color: var(--text-main);
  font-family: inherit;
  font-size: 0.875rem;
  padding: 0.45rem 0;
  min-width: 180px;
}

.filename-ext {
  font-weight: 700;
  color: var(--text-light);
}

.merge-action-group {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

/* 3. Result State: Merge Success Card */
.success-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  padding: clamp(2rem, 5vw, 3rem) 1.5rem;
  text-align: center;
}

.success-icon-wrap {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-full);
  background-color: var(--success-light);
  color: var(--success);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.25rem auto;
}

.success-icon-wrap svg {
  width: 32px;
  height: 32px;
}

.success-title {
  font-size: clamp(1.4rem, 2.5vw, 1.75rem);
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.success-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.success-metrics-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background-color: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 2rem;
}

.success-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.85rem;
}

.btn-success {
  background-color: var(--success);
  color: #ffffff;
}

.btn-success:hover {
  background-color: var(--success-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(16, 185, 129, 0.35);
}

/* Spinner */
.spinner {
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: #ffffff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  display: inline-block;
}

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

/* ==========================================================================
   VISUAL SEO SECTION (BALANCED SIZING & STRICT BOUNDS)
   ========================================================================== */
#visual-seo-container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto 3.5rem auto;
  box-sizing: border-box;
}

#visual-seo-container .tool-visual-seo-section {
  padding: 0;
  width: 100%;
}

#visual-seo-container .tool-visual-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: clamp(1.75rem, 4vw, 2.5rem);
  box-shadow: var(--shadow-md);
  margin-bottom: 0;
  position: relative;
  overflow: hidden;
}

#visual-seo-container .tool-visual-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), #7c3aed);
}

#visual-seo-container .tool-visual-hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: center;
  margin-bottom: 2rem;
}

#visual-seo-container .tool-visual-title {
  font-size: clamp(1.4rem, 2.5vw, 1.85rem);
  font-weight: 800;
  color: var(--text-main);
  line-height: 1.3;
  margin-bottom: 0.75rem;
}

#visual-seo-container .tool-visual-desc {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-muted);
}

/* Strict Animation Stage Bounds - Desktop: max-width: 280-420px, max-height: 260-360px */
#visual-seo-container .tool-animation-stage {
  background: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  max-width: 380px;
  max-height: 240px;
  min-height: 180px;
  margin: 0 auto;
  position: relative;
  overflow: hidden;
}

#visual-seo-container .tool-animation-svg {
  width: 100%;
  max-width: 260px;
  max-height: 180px;
  height: auto;
  display: block;
}

#visual-seo-container .tool-workflow-wrap {
  margin-top: 1.5rem;
}

#visual-seo-container .workflow-step-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1rem;
}

#visual-seo-container .workflow-step-title {
  color: var(--text-main);
  font-size: 0.95rem;
  font-weight: 700;
}

#visual-seo-container .workflow-step-desc {
  color: var(--text-muted);
  font-size: 0.85rem;
  line-height: 1.5;
}

/* ==========================================================================
   EDITORIAL SEO ARTICLE & HOW-TO (READABLE, CENTERED)
   ========================================================================== */
.seo-article-wrap {
  width: 100%;
  max-width: 1000px;
  margin: 0 auto 3.5rem auto;
  box-sizing: border-box;
}

.seo-article {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: clamp(1.75rem, 4vw, 2.75rem);
  box-shadow: var(--shadow-sm);
}

.seo-article h2 {
  font-size: clamp(1.35rem, 2.5vw, 1.65rem);
  font-weight: 800;
  color: var(--text-main);
  margin: 2.25rem 0 0.85rem 0;
  letter-spacing: -0.02em;
}

.seo-article h2:first-of-type {
  margin-top: 0;
}

.seo-article p {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-muted);
  margin-bottom: 1.15rem;
}

.seo-article strong {
  color: var(--text-main);
}

.seo-article a {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
}

.seo-article a:hover {
  color: var(--primary-hover);
}

/* Step-by-Step List */
.how-to-steps {
  list-style: none;
  counter-reset: step-counter;
  margin: 1.25rem 0 1.75rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.how-to-steps li {
  counter-increment: step-counter;
  position: relative;
  padding-left: 2.75rem;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--text-muted);
}

.how-to-steps li::before {
  content: counter(step-counter);
  position: absolute;
  left: 0;
  top: 2px;
  width: 24px;
  height: 24px;
  border-radius: var(--radius-full);
  background-color: var(--primary);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Role / Use Cases Grid */
.use-cases-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
  margin: 1.5rem 0;
}

.use-case-card {
  background-color: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
}

.use-case-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.use-case-card p {
  font-size: 0.9rem;
  line-height: 1.55;
  color: var(--text-muted);
  margin-bottom: 0;
}

/* Internal Links Bar */
.contextual-links-box {
  margin-top: 2rem;
  padding: 1.25rem;
  background-color: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
}

.contextual-links-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--primary);
  margin-bottom: 0.65rem;
}

.contextual-links-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  list-style: none;
}

.contextual-link-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.85rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.contextual-link-tag:hover {
  border-color: var(--primary);
  color: var(--primary);
  background-color: var(--primary-light);
  transform: translateY(-1px);
}

/* ==========================================================================
   FAQ ACCORDION (CENTERED, STRICT ALIGNMENT)
   ========================================================================== */
#main-content .faq-section,
.faq-section {
  width: 100% !important;
  max-width: 1000px !important;
  margin: 0 auto 4rem auto !important;
  padding-inline: clamp(16px, 3vw, 24px) !important;
  box-sizing: border-box;
}

.faq-title {
  font-size: clamp(1.5rem, 3vw, 1.85rem);
  font-weight: 800;
  color: var(--text-main);
  text-align: center;
  margin: 0 auto 0.5rem auto;
  letter-spacing: -0.02em;
}

.faq-subtitle {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.975rem;
  margin: 0 auto 2rem auto;
}

.accordion-wrap {
  width: 100%;
  max-width: 1000px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.accordion-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.accordion-item:hover {
  border-color: var(--border-medium);
}

.accordion-header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.15rem 1.35rem;
  background: transparent;
  border: none;
  outline: none;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  text-align: left;
  cursor: pointer;
  gap: 1rem;
}

.accordion-chevron {
  width: 18px;
  height: 18px;
  color: var(--text-light);
  flex-shrink: 0;
  transition: transform 0.2s ease;
}

.accordion-item.active .accordion-chevron {
  transform: rotate(180deg);
  color: var(--primary);
}

.accordion-body {
  padding: 0 1.35rem 1.25rem 1.35rem;
  font-size: 0.95rem;
  line-height: 1.65;
  color: var(--text-muted);
  display: none;
}

.accordion-item.active .accordion-body {
  display: block;
}

/* ==========================================================================
   RELATED TOOLS (SECTION 6 STANDARDIZED COMPONENT PRESERVED)
   ========================================================================== */
#main-content .related-tools-section,
.related-tools-section {
  width: 100% !important;
  max-width: 1180px !important;
  margin: 0 auto 4.5rem auto !important;
  padding-inline: clamp(16px, 3vw, 24px) !important;
  box-sizing: border-box;
}

.related-tools-section .section-heading {
  font-size: clamp(1.4rem, 2.5vw, 1.75rem);
  font-weight: 800;
  color: var(--text-main);
  text-align: center;
  margin-bottom: 2rem;
  letter-spacing: -0.02em;
}

/* ==========================================================================
   SITE FOOTER (LOCKED BRANDING)
   ========================================================================== */
.site-footer {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  padding: 3.5rem 0 2rem 0;
  margin-top: auto;
  width: 100%;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 2.5rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
  line-height: 1.6;
  max-width: 320px;
}

.footer-col-title {
  font-size: 0.925rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   RESPONSIVE BREAKPOINTS (1024, 768, 540, 390, 360)
   ========================================================================== */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

@media (max-width: 860px) {
  .desktop-nav {
    display: none;
  }
  .menu-toggle {
    display: inline-flex;
  }
  .use-cases-grid {
    grid-template-columns: 1fr;
  }
  #visual-seo-container .tool-visual-hero-grid {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 1.5rem;
  }
  #visual-seo-container .tool-animation-stage {
    max-width: 300px;
    max-height: 220px;
  }
  #visual-seo-container .tool-animation-svg {
    max-width: 240px;
    max-height: 160px;
  }
}

@media (max-width: 540px) {
  .tool-title {
    font-size: 1.85rem;
  }
  .tool-subtitle {
    font-size: 0.95rem;
  }
  .privacy-trust-note {
    border-radius: var(--radius-lg);
    font-size: 0.78rem;
    line-height: 1.4;
    padding: 0.4rem 0.75rem;
  }
  .header-container {
    padding-inline: 1rem;
  }
  .container {
    padding-inline: 1rem;
  }
  .workspace-wrapper {
    padding-inline: 0.25rem;
  }
  .upload-card {
    padding: 1.25rem 0.75rem;
  }
  .dropzone {
    padding: 1.75rem 0.75rem;
  }
  .seo-article {
    padding: 1.5rem 1rem;
  }
  .workspace-header {
    flex-direction: column;
    align-items: stretch;
  }
  .workspace-top-actions {
    justify-content: space-between;
  }
  .pdf-card {
    padding: 0.65rem 0.65rem;
    gap: 0.5rem;
  }
  .card-left-group {
    gap: 0.5rem;
  }
  .pdf-preview-box {
    width: 48px;
    height: 64px;
    min-width: 48px;
    max-width: 48px;
  }
  .file-name {
    max-width: 135px;
    font-size: 0.825rem;
  }
  .file-specs,
  .file-meta {
    font-size: 0.72rem;
  }
  .card-ctrl-btn,
  .btn-card-ctrl {
    width: 28px;
    height: 28px;
  }
  .card-ctrl-btn svg,
  .btn-card-ctrl svg {
    width: 13px;
    height: 13px;
  }
  .workspace-footer {
    flex-direction: column;
    align-items: stretch;
  }
  .filename-input-group {
    flex-direction: column;
    align-items: stretch;
  }
  .filename-input-wrap {
    width: 100%;
  }
  .merge-action-group {
    width: 100%;
  }
  .merge-action-group .btn {
    width: 100%;
  }
  #visual-seo-container .tool-animation-stage {
    max-width: 240px;
    max-height: 180px;
  }
  #visual-seo-container .tool-animation-svg {
    max-width: 200px;
    max-height: 140px;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }
}

@media (max-width: 390px) {
  .pdf-card {
    padding: 0.5rem 0.4rem;
    gap: 0.35rem;
  }
  .card-left-group {
    gap: 0.35rem;
  }
  .order-badge {
    width: 22px;
    height: 22px;
    font-size: 0.7rem;
  }
  .pdf-preview-box {
    width: 42px;
    height: 56px;
    min-width: 42px;
    max-width: 42px;
  }
  .file-name {
    max-width: 90px;
    font-size: 0.78rem;
  }
  .file-specs,
  .file-meta {
    font-size: 0.68rem;
  }
  .card-right-group,
  .card-actions-group {
    gap: 0.2rem;
  }
  .card-ctrl-btn,
  .btn-card-ctrl {
    width: 26px;
    height: 26px;
  }
}