/* ==========================================================================
   Facebook Cover Photo Sizer — Modern CSS
   ========================================================================== */

:root {
  /* Dark theme palette (Default) */
  --bg-primary: #0f141c;
  --bg-secondary: #161d2a;
  --bg-surface: #1e2738;
  --bg-hover: #26334a;
  --border-color: #2b384e;
  --border-focus: #3b82f6;

  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --accent-blue: #1877f2;
  --accent-blue-hover: #166fe5;
  --accent-blue-light: rgba(24, 119, 242, 0.15);

  --safe-green: #10b981;
  --safe-green-light: rgba(16, 185, 129, 0.2);
  --crop-orange: #f59e0b;
  --crop-orange-light: rgba(245, 158, 11, 0.2);
  --crop-blue: #06b6d4;
  --crop-blue-light: rgba(6, 182, 212, 0.2);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px -1px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 25px -3px rgba(0, 0, 0, 0.5);

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --fb-blue: #1877f2;
  --fb-nav-bg: #242526;
  --fb-body-bg: #18191a;
  --fb-card-bg: #242526;
  --fb-text: #e4e6eb;
  --fb-text-sub: #b0b3b8;
}

body.theme-light {
  --bg-primary: #f1f5f9;
  --bg-secondary: #ffffff;
  --bg-surface: #f8fafc;
  --bg-hover: #e2e8f0;
  --border-color: #cbd5e1;
  --border-focus: #2563eb;

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;

  --fb-blue: #1877f2;
  --fb-nav-bg: #ffffff;
  --fb-body-bg: #f0f2f5;
  --fb-card-bg: #ffffff;
  --fb-text: #050505;
  --fb-text-sub: #65676b;
}

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

html, body {
  height: 100%;
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  scrollbar-color: var(--border-color) var(--bg-primary);
  scrollbar-width: thin;
}

/* Focus indicator */
:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Icons */
.icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.icon-sm {
  width: 14px;
  height: 14px;
}

.hidden {
  display: none !important;
}

/* ==========================================================================
   Header
   ========================================================================== */
.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 24px;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, #1877f2, #0d5bbd);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
}

.brand-icon svg {
  width: 22px;
  height: 22px;
}

.header-brand h1 {
  font-size: 1.15rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

.header-brand .badge {
  font-size: 0.72rem;
  font-weight: 600;
  background-color: var(--accent-blue-light);
  color: #3b82f6;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(59, 130, 246, 0.3);
}

.tagline {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease-in-out;
  user-select: none;
}

.btn-primary {
  background-color: var(--accent-blue);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--accent-blue-hover);
}

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

.btn-secondary:hover {
  background-color: var(--bg-hover);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: var(--border-color);
}

.btn-ghost:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
}

.btn-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-icon:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
}

.btn-mini {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

.btn-mini:hover {
  background-color: var(--bg-hover);
}

.btn-sm {
  padding: 6px 10px;
  font-size: 0.775rem;
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-sm:hover {
  background-color: var(--bg-hover);
}

.btn-chip {
  padding: 5px 10px;
  font-size: 0.75rem;
  border-radius: var(--radius-full);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-chip:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--accent-blue);
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Layout Architecture
   ========================================================================== */
.app-layout {
  display: grid;
  grid-template-columns: 360px 1fr;
  height: calc(100vh - 65px);
  overflow: hidden;
}

@media (max-width: 1024px) {
  .app-layout {
    grid-template-columns: 1fr;
    height: auto;
    overflow: visible;
  }
}

/* ==========================================================================
   Sidebar Controls
   ========================================================================== */
.sidebar-controls {
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  padding: 18px 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.panel-section {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border-color);
}

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

.section-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.step-num {
  width: 20px;
  height: 20px;
  border-radius: var(--radius-full);
  background-color: var(--accent-blue-light);
  color: #3b82f6;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
}

/* Source Mode Toggle (Upload vs AI) */
.source-mode-toggle {
  display: flex;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 3px;
  gap: 4px;
}

.source-mode-btn {
  flex: 1;
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 8px 10px;
  border: none;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.source-mode-btn:hover {
  color: var(--text-primary);
}

.source-mode-btn.active {
  background-color: var(--accent-blue);
  color: #ffffff;
  box-shadow: var(--shadow-sm);
}

.source-pane {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* AI Generator Box */
.ai-generator-box {
  display: flex;
  flex-direction: column;
  gap: 10px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 12px;
}

.ai-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-primary);
}

.ai-prompt-textarea {
  width: 100%;
  font-family: inherit;
  font-size: 0.825rem;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
  resize: vertical;
  line-height: 1.4;
  outline: none;
  transition: border-color 0.15s ease;
}

.ai-prompt-textarea:focus {
  border-color: var(--border-focus);
}

.ai-style-selector {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.style-label, .ideas-label {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
}

.style-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
}

.style-chip {
  font-size: 0.72rem;
  padding: 4px 8px;
  border-radius: var(--radius-full);
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
}

.style-chip:hover {
  border-color: var(--accent-blue);
  color: var(--text-primary);
}

.style-chip.active {
  background-color: var(--accent-blue-light);
  border-color: var(--accent-blue);
  color: #38bdf8;
  font-weight: 600;
}

.ai-ideas-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.ideas-scroll {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.btn-idea {
  text-align: left;
  font-size: 0.75rem;
  padding: 5px 8px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-idea:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--accent-blue);
}

.ai-gen-btn {
  background: linear-gradient(135deg, #1877f2, #7c3aed);
  color: #ffffff;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 10px 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 4px;
}

.ai-gen-btn:hover {
  background: linear-gradient(135deg, #166fe5, #6d28d9);
}

.ai-gen-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.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;
}

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

.ai-status-text {
  font-size: 0.72rem;
  color: var(--text-muted);
  text-align: center;
}

/* Drop Zone */
.drop-zone {
  border: 2px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px 14px;
  text-align: center;
  background-color: var(--bg-surface);
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
}

.drop-zone:hover, .drop-zone.dragover {
  border-color: var(--accent-blue);
  background-color: var(--accent-blue-light);
}

.file-input-hidden {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

.drop-icon {
  width: 32px;
  height: 32px;
  color: var(--accent-blue);
  margin-bottom: 6px;
}

.drop-prompt {
  font-size: 0.85rem;
  color: var(--text-primary);
}

.drop-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 2px;
}

.sample-picker {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.sample-label {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.sample-buttons {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

/* Control groups & sliders */
.control-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.control-label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.value-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-primary);
  background-color: var(--bg-surface);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-color);
}

.slider-with-buttons {
  display: flex;
  align-items: center;
  gap: 8px;
}

input[type="range"] {
  flex: 1;
  accent-color: var(--accent-blue);
  height: 6px;
  background-color: var(--bg-surface);
  border-radius: var(--radius-full);
  cursor: pointer;
}

/* Fit Mode Presets */
.fit-mode-selector {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.fit-buttons-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
}

.btn-fit {
  text-align: left;
  padding: 8px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 8px;
}

.btn-fit:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--accent-blue);
}

.btn-fit.active {
  background-color: var(--accent-blue-light);
  border-color: var(--accent-blue);
  color: #38bdf8;
  box-shadow: var(--shadow-sm);
}

/* Quick transforms */
.quick-transforms {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
}

.quick-transforms.secondary {
  grid-template-columns: repeat(4, 1fr);
}

.form-select {
  font-family: inherit;
  font-size: 0.825rem;
  color: var(--text-primary);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 8px 10px;
  cursor: pointer;
}

.color-picker-wrapper {
  display: flex;
  align-items: center;
  gap: 8px;
}

input[type="color"] {
  border: none;
  width: 28px;
  height: 28px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: none;
}

/* Switches & checkboxes */
.switches-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.switch-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 8px 10px;
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
  cursor: pointer;
  user-select: none;
  transition: background 0.15s ease;
}

.switch-row:hover {
  background-color: var(--bg-hover);
}

.switch-row input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.switch-ui {
  width: 34px;
  height: 18px;
  border-radius: var(--radius-full);
  background-color: var(--border-color);
  position: relative;
  flex-shrink: 0;
  margin-top: 2px;
  transition: background-color 0.2s ease;
}

.switch-ui::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background-color: #ffffff;
  transition: transform 0.2s ease;
}

.switch-row input[type="checkbox"]:checked + .switch-ui {
  background-color: var(--accent-blue);
}

.switch-row input[type="checkbox"]:checked + .switch-ui::after {
  transform: translateX(16px);
}

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

.switch-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-primary);
}

.switch-label.safe-label {
  color: var(--safe-green);
}

.switch-label.desktop-label {
  color: var(--crop-orange);
}

.switch-label.mobile-label {
  color: var(--crop-blue);
}

.switch-desc {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.download-actions {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ==========================================================================
   Main Workspace
   ========================================================================== */
.main-workspace {
  display: flex;
  flex-direction: column;
  background-color: var(--bg-primary);
  overflow-y: auto;
}

.view-tabs {
  display: flex;
  gap: 4px;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  padding: 8px 16px 0 16px;
  overflow-x: auto;
}

.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  padding: 10px 16px;
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.tab-btn:hover {
  color: var(--text-primary);
}

.tab-btn.active {
  color: var(--accent-blue);
  border-bottom-color: var(--accent-blue);
}

.tab-panels {
  flex: 1;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-y: auto;
}

.tab-panel {
  display: none;
  flex-direction: column;
  height: 100%;
}

.tab-panel.active {
  display: flex;
}

/* ==========================================================================
   Editor Pane & Interactive Canvas
   ========================================================================== */
.canvas-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 20px;
  background-color: rgba(22, 29, 42, 0.6);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(8px);
  flex-wrap: wrap;
  gap: 10px;
}

.toolbar-hint {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.legend-pills {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.legend-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75rem;
  color: var(--text-secondary);
  background-color: var(--bg-surface);
  padding: 3px 8px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-color);
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.dot.green { background-color: var(--safe-green); box-shadow: 0 0 6px var(--safe-green); }
.dot.orange { background-color: var(--crop-orange); box-shadow: 0 0 6px var(--crop-orange); }
.dot.blue { background-color: var(--crop-blue); box-shadow: 0 0 6px var(--crop-blue); }

.canvas-container {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  overflow: hidden;
  background: radial-gradient(circle at center, var(--bg-surface) 0%, var(--bg-primary) 100%);
  position: relative;
  min-height: 420px;
}

.canvas-wrapper {
  position: relative;
  width: 100%;
  max-width: 960px;
  aspect-ratio: 1640 / 720;
  box-shadow: 0 12px 36px -4px rgba(0, 0, 0, 0.6);
  border-radius: var(--radius-md);
  overflow: hidden;
  outline: 1px solid var(--border-color);
  border: none;
  background-color: #000000;
  touch-action: none;
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
}

.canvas-wrapper.dragging {
  cursor: grabbing;
}

.canvas-wrapper canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: block;
}

#bgCanvas {
  z-index: 1;
}

#mainCanvas {
  z-index: 2;
}

#guideCanvas {
  z-index: 3;
  pointer-events: none;
}

.canvas-footer-stats {
  display: flex;
  justify-content: space-around;
  padding: 10px 16px;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  font-size: 0.775rem;
  flex-wrap: wrap;
  gap: 8px;
}

.stat-item {
  display: flex;
  gap: 6px;
}

.stat-label {
  color: var(--text-muted);
}

.stat-value {
  color: var(--text-primary);
  font-weight: 600;
  font-family: var(--font-mono);
}

.stat-item.safe-stat .stat-value {
  color: var(--safe-green);
}

/* ==========================================================================
   Desktop Facebook Simulator
   ========================================================================== */
.mockup-header-bar {
  background-color: var(--bg-surface);
  padding: 8px 16px;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-align: center;
}

.fb-desktop-mockup {
  background-color: var(--fb-body-bg);
  min-height: 100%;
  display: flex;
  flex-direction: column;
  padding-bottom: 40px;
}

.fb-desktop-nav {
  height: 56px;
  background-color: var(--fb-nav-bg);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
}

.fb-nav-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.fb-logo-circle {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--fb-blue);
  color: #ffffff;
  font-weight: 800;
  font-size: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.fb-search-bar {
  background-color: rgba(255, 255, 255, 0.1);
  color: var(--fb-text-sub);
  padding: 8px 14px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  width: 200px;
}

.fb-nav-center {
  display: flex;
  gap: 20px;
}

.nav-tab-icon {
  font-size: 1.2rem;
  padding: 8px 24px;
  cursor: default;
  border-radius: var(--radius-sm);
}

.nav-tab-icon.active {
  border-bottom: 3px solid var(--fb-blue);
}

.fb-nav-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-circle-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
}

.nav-avatar-mini {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, #10b981, #06b6d4);
}

.fb-profile-container {
  max-width: 940px;
  width: 100%;
  margin: 0 auto;
  background-color: var(--fb-card-bg);
  box-shadow: var(--shadow-sm);
  border-bottom-left-radius: var(--radius-md);
  border-bottom-right-radius: var(--radius-md);
}

/* FB Desktop Cover Frame: Exactly 1640x624 ratio (820x312) */
.fb-cover-desktop-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 1640 / 624;
  overflow: hidden;
  background-color: #000000;
}

.sim-canvas {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.cover-crop-indicator {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 5;
}

.crop-tag {
  background-color: rgba(0, 0, 0, 0.7);
  color: #ffffff;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  backdrop-filter: blur(4px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.fb-edit-cover-btn {
  position: absolute;
  bottom: 16px;
  right: 24px;
  background-color: rgba(255, 255, 255, 0.95);
  color: #050505;
  border: none;
  font-weight: 600;
  font-size: 0.85rem;
  padding: 8px 14px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  cursor: default;
}

.fb-profile-header-info {
  display: flex;
  align-items: flex-end;
  padding: 0 32px 16px 32px;
  position: relative;
  gap: 20px;
}

.fb-avatar-wrapper {
  margin-top: -80px;
  position: relative;
  z-index: 10;
}

.fb-avatar-circle {
  width: 168px;
  height: 168px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  border: 4px solid var(--fb-card-bg);
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.avatar-letter {
  font-size: 3.5rem;
  font-weight: 700;
  color: #ffffff;
}

.fb-user-details {
  flex: 1;
  padding-bottom: 8px;
}

.fb-user-name {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--fb-text);
  line-height: 1.2;
}

.fb-user-sub {
  font-size: 0.875rem;
  color: var(--fb-text-sub);
  margin-top: 4px;
}

.fb-profile-actions {
  display: flex;
  gap: 10px;
  padding-bottom: 8px;
}

.fb-btn-primary {
  background-color: var(--fb-blue);
  color: #ffffff;
  border: none;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  cursor: default;
}

.fb-btn-secondary {
  background-color: rgba(255, 255, 255, 0.15);
  color: var(--fb-text);
  border: none;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  cursor: default;
}

.fb-tabs-bar {
  display: flex;
  gap: 10px;
  padding: 0 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.fb-tab {
  padding: 14px 16px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--fb-text-sub);
  cursor: default;
}

.fb-tab.active {
  color: var(--fb-blue);
  border-bottom: 3px solid var(--fb-blue);
}

/* ==========================================================================
   Mobile Facebook Simulator
   ========================================================================== */
.mobile-device-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 24px 16px;
  flex: 1;
}

.smartphone-frame {
  width: 380px;
  height: 720px;
  border-radius: 44px;
  background-color: #121212;
  border: 10px solid #2a2a2a;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

.phone-speaker {
  width: 60px;
  height: 4px;
  background-color: #333333;
  border-radius: var(--radius-full);
  position: absolute;
  top: 12px;
  left: calc(50% - 30px);
  z-index: 20;
}

.phone-camera {
  width: 10px;
  height: 10px;
  background-color: #222222;
  border-radius: 50%;
  position: absolute;
  top: 10px;
  right: 120px;
  z-index: 20;
}

.phone-screen {
  flex: 1;
  background-color: var(--fb-body-bg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.mobile-status-bar {
  height: 28px;
  padding: 6px 20px 0 20px;
  display: flex;
  justify-content: space-between;
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--fb-text);
  background-color: var(--fb-nav-bg);
}

.fb-mobile-top-bar {
  height: 44px;
  background-color: var(--fb-nav-bg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--fb-text);
}

.mobile-profile-scroll {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

/* Mobile Cover: 1280x720 ratio = 16:9 ratio */
.fb-cover-mobile-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background-color: #000000;
  overflow: hidden;
}

.mobile-cam-btn {
  position: absolute;
  bottom: 10px;
  right: 10px;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: rgba(0, 0, 0, 0.6);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
}

.mobile-crop-badge {
  position: absolute;
  top: 10px;
  left: 10px;
  background-color: rgba(0, 0, 0, 0.7);
  color: var(--crop-blue);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.7rem;
  font-weight: 600;
  border: 1px solid rgba(6, 182, 212, 0.3);
}

.fb-mobile-avatar-row {
  margin-top: -55px;
  padding-left: 16px;
  position: relative;
  z-index: 10;
}

.fb-mobile-avatar {
  width: 105px;
  height: 105px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  border: 4px solid var(--fb-body-bg);
  display: flex;
  align-items: center;
  justify-content: center;
}

.fb-mobile-avatar .avatar-letter {
  font-size: 2.2rem;
}

.fb-mobile-info {
  padding: 10px 16px 20px 16px;
}

.fb-mobile-name {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--fb-text);
}

.fb-mobile-bio {
  font-size: 0.8rem;
  color: var(--fb-text-sub);
  margin-top: 4px;
}

.fb-mobile-buttons {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.m-btn-primary {
  flex: 1;
  background-color: var(--fb-blue);
  color: #ffffff;
  border: none;
  padding: 8px 0;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.8rem;
}

.m-btn-secondary {
  flex: 1;
  background-color: rgba(255, 255, 255, 0.15);
  color: var(--fb-text);
  border: none;
  padding: 8px 0;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.8rem;
}

.m-btn-icon {
  width: 36px;
  background-color: rgba(255, 255, 255, 0.15);
  color: var(--fb-text);
  border: none;
  border-radius: var(--radius-sm);
}

.fb-mobile-feed-teaser {
  margin-top: 20px;
  background-color: var(--fb-card-bg);
  border-radius: var(--radius-md);
  padding: 12px;
}

.teaser-card {
  display: flex;
  gap: 10px;
  align-items: center;
}

.teaser-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.1);
}

.teaser-line {
  flex: 1;
  height: 12px;
  border-radius: var(--radius-full);
  background-color: rgba(255, 255, 255, 0.08);
}

.phone-home-indicator {
  width: 120px;
  height: 4px;
  background-color: rgba(255, 255, 255, 0.4);
  border-radius: var(--radius-full);
  margin: 6px auto;
}

/* ==========================================================================
   Dual Comparison View
   ========================================================================== */
.dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  padding: 24px;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

@media (max-width: 900px) {
  .dual-grid {
    grid-template-columns: 1fr;
  }
}

.dual-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  box-shadow: var(--shadow-sm);
}

.dual-card-title {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.platform-tag {
  font-size: 0.95rem;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.platform-tag.pc { color: var(--crop-orange); }
.platform-tag.phone { color: var(--crop-blue); }

.crop-info {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.dual-preview-box {
  width: 100%;
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: #000000;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-md);
}

.dual-preview-box.desktop-aspect {
  aspect-ratio: 1640 / 624;
}

.dual-preview-box.mobile-aspect {
  aspect-ratio: 1280 / 720;
}

.dual-preview-box canvas {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.dual-caption {
  font-size: 0.775rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* ==========================================================================
   Dialog Modal
   ========================================================================== */
.guide-dialog {
  margin: auto;
  padding: 0;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  max-width: 600px;
  width: 90%;
  box-shadow: var(--shadow-lg);
}

.guide-dialog::backdrop {
  background-color: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(4px);
}

.dialog-content {
  display: flex;
  flex-direction: column;
}

.dialog-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-color);
}

.dialog-header h3 {
  font-size: 1.1rem;
  font-weight: 700;
}

.btn-close {
  background: transparent;
  border: none;
  font-size: 1.2rem;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
}

.btn-close:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
}

.dialog-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  font-size: 0.875rem;
}

.explanation-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

@media (max-width: 500px) {
  .explanation-grid {
    grid-template-columns: 1fr;
  }
}

.explain-box {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 12px;
}

.explain-box h4 {
  font-size: 0.9rem;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.explain-box p {
  color: var(--text-secondary);
  font-size: 0.8rem;
  line-height: 1.4;
}

.rule-box {
  background-color: var(--safe-green-light);
  border: 1px solid rgba(16, 185, 129, 0.4);
  border-radius: var(--radius-md);
  padding: 14px;
}

.rule-box h4 {
  color: var(--safe-green);
  font-size: 0.95rem;
  margin-bottom: 4px;
}

.rule-box p {
  color: var(--text-primary);
  font-size: 0.825rem;
}

.specs-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8rem;
}

.specs-table th, .specs-table td {
  padding: 8px 10px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.specs-table th {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
}

.badge-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: 6px;
}

.badge-dot.green { background-color: var(--safe-green); }
.badge-dot.orange { background-color: var(--crop-orange); }
.badge-dot.blue { background-color: var(--crop-blue); }

.dialog-footer {
  padding: 14px 20px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: flex-end;
}

/* ==========================================================================
   Toast Notification
   ========================================================================== */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 12px 20px;
  font-size: 0.875rem;
  font-weight: 600;
  box-shadow: var(--shadow-lg);
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideUp 0.25s ease-out;
}

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