/* ==========================================================================
   AI Background Remover - Unified Production Design System
   Pure CSS3 with Mobile-First Responsive Architecture & Zero External Bloat
   ========================================================================== */

:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --primary-glow: rgba(37, 99, 235, 0.18);
  --accent: #059669;
  --accent-light: #ecfdf5;
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-subtle: #94a3b8;
  --bg-page: #f8fafc;
  --bg-card: #ffffff;
  --bg-elevated: #ffffff;
  --border-subtle: #e2e8f0;
  --border-focus: #3b82f6;
  --shadow-sm: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 20px 25px -5px rgba(15, 23, 42, 0.1), 0 8px 10px -6px rgba(15, 23, 42, 0.05);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  --header-height: 70px;
  --container-max: 1200px;
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
}

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

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-main);
  background-color: var(--bg-page);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

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

/* Typography Standards */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-main);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 4vw + 1rem, 3.25rem); }
h2 { font-size: clamp(1.5rem, 2.5vw + 0.75rem, 2.25rem); }
h3 { font-size: clamp(1.2rem, 1.5vw + 0.5rem, 1.5rem); }
h4 { font-size: 1.15rem; }

p {
  color: var(--text-muted);
  margin-bottom: 1rem;
  line-height: 1.7;
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

.section {
  padding: 4.5rem 0;
}

.section-alt {
  background-color: #ffffff;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.mx-auto { margin-left: auto; margin-right: auto; }

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all var(--transition-normal);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--text-main);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand-icon {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--primary) 0%, #4338ca 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-weight: 900;
  font-size: 0.9rem;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.35);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  list-style: none;
}

.nav-link {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color var(--transition-fast);
  padding: 0.5rem 0.25rem;
  position: relative;
}

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

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background-color: var(--primary);
  border-radius: var(--radius-full);
}

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

.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text-main);
}

/* Badges & Buttons */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  font-size: 0.825rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background-color: var(--primary-light);
  color: var(--primary);
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.badge-success {
  background-color: var(--accent-light);
  color: var(--accent);
  border-color: rgba(5, 150, 105, 0.2);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

.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);
  color: #ffffff;
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.35);
}

.btn-secondary {
  background-color: #ffffff;
  color: var(--text-main);
  border-color: var(--border-subtle);
}

.btn-secondary:hover {
  background-color: #f1f5f9;
  border-color: #cbd5e1;
  color: var(--text-main);
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 0.9rem 1.85rem;
  font-size: 1.05rem;
}

.btn-outline {
  background: transparent;
  border-color: var(--border-subtle);
  color: var(--text-main);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  background-color: var(--primary-light);
}

.btn-group {
  display: inline-flex;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  overflow: hidden;
}

.btn-group .btn {
  border-radius: 0;
  border: none;
  border-right: 1px solid var(--border-subtle);
  padding: 0.4rem 0.75rem;
  font-size: 0.85rem;
  background: #ffffff;
}

.btn-group .btn:last-child {
  border-right: none;
}

.btn-group .btn.active {
  background-color: var(--primary-light);
  color: var(--primary);
  font-weight: 700;
}

/* ==========================================================================
   TOOL WORKSPACE & INTERACTIVE APP
   ========================================================================== */

.tool-app-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  margin: 2rem 0;
}

.tool-header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background-color: #ffffff;
  border-bottom: 1px solid var(--border-subtle);
  flex-wrap: wrap;
  gap: 1rem;
}

.tool-status-badge {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-light);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(5, 150, 105, 0.7); }
  70% { transform: scale(1); box-shadow: 0 0 0 6px rgba(5, 150, 105, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(5, 150, 105, 0); }
}

/* Dropzone */
.dropzone-container {
  padding: 3.5rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  border: 2px dashed #cbd5e1;
  border-radius: var(--radius-md);
  margin: 1.5rem;
  background-color: #f8fafc;
  cursor: pointer;
  transition: all var(--transition-normal);
}

.dropzone-container:hover,
.dropzone-container.drag-over {
  border-color: var(--primary);
  background-color: var(--primary-light);
}

.dropzone-icon {
  width: 64px;
  height: 64px;
  margin-bottom: 1.25rem;
  color: var(--primary);
}

.file-input-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.paste-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.6rem;
  background: #e2e8f0;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-top: 0.5rem;
}

/* Presets Demo Strip */
.demo-strip {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.demo-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  background-color: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.demo-chip:hover {
  border-color: var(--primary);
  color: var(--primary);
  background-color: var(--primary-light);
  transform: translateY(-1px);
}

.demo-chip-icon {
  font-size: 1rem;
}

/* Processing Workspace */
.workspace-container {
  display: none;
  padding: 1.5rem;
}

.workspace-container.active {
  display: block;
}

.preview-stage {
  position: relative;
  width: 100%;
  height: 500px;
  max-height: 65vh;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #f1f5f9;
}

/* Split Comparison Slider */
.split-viewer {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
  user-select: none;
  -webkit-user-select: none;
  cursor: crosshair;
}

.split-canvas-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.split-before-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  clip-path: polygon(0 0, 50% 0, 50% 100%, 0 100%);
  background-color: #ffffff;
  pointer-events: none;
}

.split-before-img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.split-slider-line {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 3px;
  background-color: #ffffff;
  box-shadow: 0 0 8px rgba(0, 0, 0, 0.4);
  cursor: ew-resize;
  transform: translateX(-50%);
  z-index: 10;
}

.split-slider-button {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: #ffffff;
  border: 2px solid var(--primary);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.25);
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: ew-resize;
  color: var(--primary);
  font-size: 14px;
}

/* Touch-up Brush Cursor Overlay */
.brush-cursor-indicator {
  position: absolute;
  pointer-events: none;
  border-radius: 50%;
  border: 2px solid rgba(37, 99, 235, 0.9);
  background-color: rgba(37, 99, 235, 0.15);
  transform: translate(-50%, -50%);
  display: none;
  z-index: 20;
}

.brush-cursor-indicator.erase-mode {
  border-color: rgba(225, 29, 72, 0.9);
  background-color: rgba(225, 29, 72, 0.15);
}

.brush-cursor-indicator.restore-mode {
  border-color: rgba(5, 150, 105, 0.9);
  background-color: rgba(5, 150, 105, 0.15);
}

/* Toolbar & Sub-bars */
.editor-subbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  flex-wrap: wrap;
  gap: 0.75rem;
}

.subbar-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.brush-mode-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.8rem;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  background-color: #ffffff;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.brush-mode-btn:hover {
  border-color: #cbd5e1;
  color: var(--text-main);
}

.brush-mode-btn.active {
  background-color: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary);
}

/* Tool Controls Toolbar */
.tool-controls-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 1rem;
  padding: 1.25rem;
  background-color: #f8fafc;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.control-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.color-options-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.color-swatch {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  border: 2px solid var(--border-subtle);
  cursor: pointer;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.color-swatch:hover,
.color-swatch.active {
  transform: scale(1.1);
  border-color: var(--primary);
  box-shadow: 0 0 0 2px var(--primary-glow);
}

.color-picker-input {
  width: 32px;
  height: 32px;
  padding: 0;
  border: 2px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: none;
}

/* Export & Actions Row */
.action-buttons-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border-subtle);
  flex-wrap: wrap;
  gap: 1rem;
}

/* Sliders & Range Inputs */
.range-slider {
  width: 100%;
  accent-color: var(--primary);
  cursor: pointer;
}

/* Processing Overlay */
.processing-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(4px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  z-index: 30;
  transition: opacity 0.2s ease;
}

.spinner {
  width: 42px;
  height: 42px;
  border: 4px solid var(--primary-light);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* ==========================================================================
   CONTENT & SEO ARCHITECTURE
   ========================================================================== */

/* Breadcrumbs */
.breadcrumbs-nav {
  padding: 1rem 0;
  font-size: 0.875rem;
  color: var(--text-muted);
}

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

.breadcrumbs-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumbs-item a {
  color: var(--text-muted);
}

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

.breadcrumbs-separator {
  color: var(--text-subtle);
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
}

.feature-card {
  background-color: var(--bg-card);
  padding: 2rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: #cbd5e1;
}

.feature-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background-color: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.25rem;
}

/* Comparison Table */
.table-responsive-container {
  overflow-x: auto;
  margin: 2.5rem 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  background-color: #ffffff;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.comparison-table th,
.comparison-table td {
  padding: 1.15rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

.comparison-table th {
  background-color: #f8fafc;
  color: var(--text-main);
  font-weight: 700;
}

.comparison-table tr:last-child td {
  border-bottom: none;
}

.comparison-table tr:hover td {
  background-color: #f8fafc;
}

.highlight-col {
  background-color: var(--primary-light) !important;
  font-weight: 600;
  color: var(--primary);
}

/* FAQ Accordion */
.faq-accordion {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background-color: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

.faq-item.open {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.faq-question {
  width: 100%;
  padding: 1.25rem 1.5rem;
  text-align: left;
  background: none;
  border: none;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.faq-question:hover {
  color: var(--primary);
}

.faq-icon {
  font-size: 0.8rem;
  transition: transform var(--transition-normal);
  color: var(--text-muted);
}

.faq-item.open .faq-icon {
  transform: rotate(180deg);
  color: var(--primary);
}

.faq-answer {
  display: none;
  padding: 0 1.5rem 1.25rem 1.5rem;
  color: var(--text-muted);
  line-height: 1.7;
}

.faq-item.open .faq-answer {
  display: block;
}

/* Article & Longform Content */
.article-body {
  max-width: 860px;
  margin: 0 auto;
  font-size: 1.05rem;
  line-height: 1.8;
  color: #334155;
}

.article-body h2 {
  margin-top: 2.75rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

.article-body h3 {
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.article-body p,
.article-body ul,
.article-body ol,
.article-body blockquote {
  margin-bottom: 1.5rem;
}

.article-body ul,
.article-body ol {
  padding-left: 1.5rem;
}

.article-body li {
  margin-bottom: 0.5rem;
}

.article-body blockquote {
  padding: 1rem 1.5rem;
  background-color: var(--primary-light);
  border-left: 4px solid var(--primary);
  border-radius: var(--radius-sm);
  font-style: italic;
  color: var(--text-main);
}

/* Step Flow */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin: 2.5rem 0;
}

.step-card {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  position: relative;
}

.step-number {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: var(--primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: 1rem;
}

/* Form Styles */
.form-group {
  margin-bottom: 1.5rem;
  text-align: left;
}

.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 0.375rem;
  color: var(--text-main);
}

.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.95rem;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  background-color: #ffffff;
  color: var(--text-main);
  font-family: inherit;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

/* Toast Notifications */
.toast-notice {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background-color: #0f172a;
  color: #ffffff;
  padding: 1rem 1.5rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-xl);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  z-index: 999;
  transform: translateY(100px);
  opacity: 0;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.toast-notice.show {
  transform: translateY(0);
  opacity: 1;
}

/* Footer */
.site-footer {
  background-color: #0f172a;
  color: #94a3b8;
  padding: 4.5rem 0 2rem;
  margin-top: auto;
  border-top: 1px solid #1e293b;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 3rem;
  margin-bottom: 3.5rem;
}

.footer-brand h3 {
  color: #ffffff;
  font-size: 1.35rem;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-heading {
  color: #ffffff;
  font-size: 0.95rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-links a {
  color: #94a3b8;
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid #1e293b;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
  flex-wrap: wrap;
  gap: 1rem;
}

/* ==========================================================================
   RESPONSIVE MEDIA QUERIES
   ========================================================================== */

@media (max-width: 992px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
  }
}

@media (max-width: 768px) {
  .mobile-nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background-color: #ffffff;
    flex-direction: column;
    align-items: flex-start;
    padding: 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-lg);
    display: none;
  }

  .nav-menu.open {
    display: flex;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .preview-stage {
    height: 380px;
  }
  
  .tool-header-bar {
    flex-direction: column;
    align-items: flex-start;
  }

  .action-buttons-row {
    flex-direction: column;
    align-items: stretch;
  }

  .action-buttons-row .btn {
    width: 100%;
  }

  .editor-subbar {
    flex-direction: column;
    align-items: flex-start;
  }
}