/* ========================================
   Unifile - Modern Vibrant Styles
   Universal File Converter
   ======================================== */

/* CSS Variables - Dark Theme (Default) */
:root {
  /* Primary Gradient Colors */
  --primary-start: #667eea;
  --primary-end: #764ba2;
  --primary-gradient: linear-gradient(
    135deg,
    var(--primary-start),
    var(--primary-end)
  );

  /* Category Colors */
  --images-color: #10b981;
  --images-light: #064e3b;
  --images-gradient: linear-gradient(135deg, #10b981, #059669);

  --documents-color: #3b82f6;
  --documents-light: #1e3a8a;
  --documents-gradient: linear-gradient(135deg, #3b82f6, #1d4ed8);

  /* Accent Colors */
  --accent-purple: #8b5cf6;
  --accent-pink: #ec4899;
  --accent-cyan: #06b6d4;
  --accent-lime: #84cc16;

  /* UI Colors */
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;

  /* Background & Surface - Dark Mode Default */
  --bg-color: #0f172a;
  --bg-secondary: #1e293b;
  --bg-gradient: linear-gradient(180deg, #0f172a 0%, #1e1b4b 100%);
  --card-bg: var(--bg-secondary);
  --gradient-primary: var(--primary-gradient);
  --primary-color: var(--primary-start);

  /* Text - Dark Mode */
  --text-color: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #64748b;

  /* Borders */
  --border-color: #334155;
  --border-radius: 16px;
  --border-radius-sm: 10px;
  --border-radius-lg: 24px;
  --border-radius-full: 9999px;

  /* Shadows - Dark Mode */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 40px rgba(102, 126, 234, 0.4);

  /* Transitions */
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: all 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

/* Light Mode */
[data-theme="light"] {
  --bg-color: #f0f4ff;
  --bg-secondary: #ffffff;
  --bg-gradient: linear-gradient(180deg, #f0f4ff 0%, #e8ecff 100%);
  --card-bg: var(--bg-secondary);
  --gradient-primary: var(--primary-gradient);
  --primary-color: var(--primary-start);
  --text-color: #1e293b;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border-color: #e2e8f0;
  --images-light: #d1fae5;
  --documents-light: #dbeafe;
  --shadow-sm: 0 2px 8px rgba(102, 126, 234, 0.1);
  --shadow: 0 8px 24px rgba(102, 126, 234, 0.15);
  --shadow-lg: 0 16px 48px rgba(102, 126, 234, 0.2);
  --shadow-glow: 0 0 40px rgba(102, 126, 234, 0.3);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family:
    "Inter",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    sans-serif;
  background: var(--bg-gradient);
  color: var(--text-color);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* App Container */
.app-container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 20px;
  min-height: 100vh;
}

/* ========================================
   Header
   ======================================== */
.header {
  margin-bottom: 32px;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
  margin-bottom: 16px;
}

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

.logo-icon-wrapper {
  width: 48px;
  height: 48px;
  background: var(--primary-gradient);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.logo-icon {
  width: 28px;
  height: 28px;
  color: white;
}

.logo-text h1 {
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}

.logo-subtitle {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.header-nav {
  display: flex;
  gap: 16px;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
  border-radius: var(--border-radius-sm);
  transition: var(--transition);
}

.nav-link svg {
  width: 18px;
  height: 18px;
}

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

.github-link svg {
  width: 20px;
  height: 20px;
}

.coffee-link {
  background: linear-gradient(135deg, #ff813f, #ff5f1f) !important;
  color: white !important;
  border: none !important;
}

.coffee-link:hover {
  background: linear-gradient(135deg, #ff9f5f, #ff7f3f) !important;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 129, 63, 0.4);
}

.coffee-link svg {
  width: 18px;
  height: 18px;
  fill: white !important;
}

[data-theme="light"] .coffee-link {
  background: linear-gradient(135deg, #ff813f, #ff5f1f) !important;
  color: white !important;
}

[data-theme="light"] .coffee-link svg {
  fill: white !important;
}

/* Theme Toggle Button */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  padding: 0;
  background: var(--bg-secondary);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: var(--transition);
  position: relative;
}

.theme-toggle:hover {
  background: var(--primary-gradient);
  border-color: transparent;
}

.theme-toggle:hover svg {
  stroke: white;
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  stroke: var(--text-secondary);
  transition: var(--transition);
  position: absolute;
}

/* Dark mode (default) - show sun icon */
.theme-toggle .sun-icon {
  opacity: 1;
  transform: rotate(0deg);
}

.theme-toggle .moon-icon {
  opacity: 0;
  transform: rotate(-90deg);
}

/* Light mode - show moon icon */
[data-theme="light"] .theme-toggle .sun-icon {
  opacity: 0;
  transform: rotate(90deg);
}

[data-theme="light"] .theme-toggle .moon-icon {
  opacity: 1;
  transform: rotate(0deg);
}

/* Tagline Banner */
.tagline-banner {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--border-radius-full);
  font-size: 0.85rem;
  font-weight: 600;
}

.badge.privacy {
  background: linear-gradient(135deg, #10b981, #059669);
  color: white;
}

.badge.speed {
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: white;
}

.badge.free {
  background: linear-gradient(135deg, #8b5cf6, #7c3aed);
  color: white;
}

/* ========================================
   Main Content
   ======================================== */
.main-content {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* Category Tabs */
.category-tabs {
  display: flex;
  gap: 8px;
  padding: 8px;
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-sm);
}

.category-tab {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 16px 12px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: var(--transition);
}

.category-tab svg {
  width: 24px;
  height: 24px;
}

.category-tab:hover {
  color: var(--text-color);
  background: var(--border-color);
}

.category-tab.active {
  color: white;
  box-shadow: var(--shadow);
}

.category-tab.active[data-category="images"] {
  background: var(--images-gradient);
}

.category-tab.active[data-category="documents"] {
  background: var(--documents-gradient);
}

/* Mode Selector */
.mode-selector {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.mode-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border: 2px solid var(--border-color);
  background: var(--bg-secondary);
  color: var(--text-secondary);
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--border-radius-full);
  cursor: pointer;
  transition: var(--transition);
}

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

.mode-btn:hover {
  border-color: var(--primary-start);
  color: var(--primary-start);
  transform: translateY(-2px);
}

.mode-btn.active {
  background: var(--primary-gradient);
  border-color: transparent;
  color: white;
  box-shadow: 0 4px 16px rgba(102, 126, 234, 0.4);
}

/* ========================================
   Drop Zone
   ======================================== */
.drop-zone {
  position: relative;
  background: var(--bg-secondary);
  border: 3px dashed var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 60px 40px;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
  overflow: hidden;
}

.drop-zone::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--primary-gradient);
  opacity: 0;
  transition: var(--transition);
}

.drop-zone:hover,
.drop-zone.drag-over {
  border-color: var(--primary-start);
  transform: scale(1.01);
}

.drop-zone:hover::before,
.drop-zone.drag-over::before {
  opacity: 0.05;
}

.drop-zone.drag-over {
  border-style: solid;
  box-shadow: var(--shadow-glow);
}

.drop-zone-content {
  position: relative;
  z-index: 1;
}

.upload-icon-wrapper {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  background: var(--primary-gradient);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.25);
  animation: pulse-shadow 2s infinite;
}

@keyframes pulse-shadow {
  0%,
  100% {
    box-shadow: 0 8px 24px rgba(102, 126, 234, 0.3);
  }
  50% {
    box-shadow: 0 8px 40px rgba(102, 126, 234, 0.5);
  }
}

.upload-icon {
  width: 24px;
  height: 24px;
  color: white;
}

.drop-zone h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-color);
}

.drop-zone p {
  color: var(--text-secondary);
  margin-bottom: 20px;
}

.drop-zone input[type="file"] {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

/* Supported Formats */
.supported-formats {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  max-width: 500px;
  margin: 0 auto;
}

.format-badge {
  padding: 6px 14px;
  border-radius: var(--border-radius-full);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.format-badge.popular {
  background: var(--primary-gradient);
  color: white;
}

.format-badge.normal {
  background: var(--border-color);
  color: var(--text-secondary);
}

.format-badge.more {
  background: var(--text-muted);
  color: white;
}

/* ========================================
   Conversion Options
   ======================================== */
.conversion-options {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: 24px;
  box-shadow: var(--shadow);
}

.options-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.options-header h3 {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-color);
}

.options-header h3 svg {
  width: 20px;
  height: 20px;
  color: var(--primary-start);
}

.detected-format {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--border-color);
  border-radius: var(--border-radius-full);
  font-size: 0.85rem;
}

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

.detected-value {
  font-weight: 700;
  color: var(--primary-start);
  text-transform: uppercase;
}

.format-selector {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.format-selector label {
  font-weight: 600;
  color: var(--text-secondary);
}

.format-select {
  flex: 1;
  padding: 12px 16px;
  border: 2px solid var(--border-color);
  background: var(--bg-secondary);
  color: var(--text-color);
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: var(--transition);
}

.format-select:focus {
  outline: none;
  border-color: var(--primary-start);
  box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
}

.output-folder-selector {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 8px;
}

.output-folder-selector label {
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
}

.output-folder-input {
  flex: 1;
  padding: 12px 16px;
  border: 2px solid var(--border-color);
  background: var(--bg-secondary);
  color: var(--text-color);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--border-radius-sm);
  transition: var(--transition);
}

.output-folder-input:focus {
  outline: none;
  border-color: var(--primary-start);
  box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
}

.output-folder-hint {
  margin: 0 0 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Quality Slider */
.quality-options {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.quality-slider label {
  display: flex;
  justify-content: space-between;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.quality-slider input[type="range"] {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--border-color);
  appearance: none;
  cursor: pointer;
}

.quality-slider input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-gradient);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(102, 126, 234, 0.4);
  transition: var(--transition);
}

.quality-slider input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

.privacy-toggle {
  margin-top: 8px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.privacy-toggle input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--primary-start);
}

.format-note {
  margin-top: 16px;
  padding: 12px 16px;
  background: #fef3c7;
  color: #92400e;
  border-radius: var(--border-radius-sm);
  font-size: 0.85rem;
  border-left: 4px solid #f59e0b;
}

@media (prefers-color-scheme: dark) {
  .format-note {
    background: #78350f;
    color: #fcd34d;
  }
}

/* ========================================
   File List
   ======================================== */
.file-list-container {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: 24px;
  box-shadow: var(--shadow);
}

.file-list-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
  flex-wrap: wrap;
  gap: 12px;
}

.file-list-header h3 {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1rem;
  font-weight: 600;
}

.file-list-header h3 svg {
  width: 20px;
  height: 20px;
  color: var(--primary-start);
}

.file-actions {
  display: flex;
  gap: 8px;
}

.action-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  border: none;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: var(--transition);
}

.action-btn svg {
  width: 16px;
  height: 16px;
}

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

.action-btn.secondary:hover {
  background: var(--primary-gradient);
  color: white;
}

.action-btn.danger {
  background: #fee2e2;
  color: #dc2626;
}

.action-btn.danger:hover {
  background: #dc2626;
  color: white;
}

.drag-hint {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

/* File List Items */
.file-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 400px;
  overflow-y: auto;
}

.file-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: var(--bg-color);
  border: 2px solid transparent;
  border-radius: var(--border-radius-sm);
  cursor: grab;
  transition: var(--transition);
}

.file-item:hover {
  border-color: var(--primary-start);
  background: var(--bg-secondary);
}

.file-item.dragging {
  opacity: 0.5;
  cursor: grabbing;
}

.file-item.drag-over {
  border-color: var(--primary-start);
  background: rgba(102, 126, 234, 0.1);
}

.file-item .drag-handle {
  color: var(--text-muted);
  cursor: grab;
}

.file-item .drag-handle svg {
  width: 20px;
  height: 20px;
}

.file-item .file-icon {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.file-item .file-icon svg {
  width: 18px;
  height: 18px;
}

.file-item .file-icon.images {
  background: var(--images-light);
  color: var(--images-color);
}

.file-item .file-icon.documents {
  background: var(--documents-light);
  color: var(--documents-color);
}

.file-item .file-info {
  flex: 1;
  min-width: 0;
}

.file-item .file-name {
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-item .file-meta {
  display: flex;
  gap: 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.file-item .file-format {
  padding: 2px 8px;
  background: var(--border-color);
  border-radius: 4px;
  text-transform: uppercase;
  font-weight: 600;
  font-size: 0.7rem;
}

.file-item .file-preview {
  width: 50px;
  height: 50px;
  border-radius: 8px;
  object-fit: cover;
  flex-shrink: 0;
}

.file-item .remove-btn {
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  flex-shrink: 0;
}

.file-item .remove-btn:hover {
  background: #fee2e2;
  color: #dc2626;
}

.file-item .remove-btn svg {
  width: 18px;
  height: 18px;
}

/* ========================================
   Process Button
   ======================================== */
.process-btn {
  position: relative;
  width: 100%;
  padding: 20px 32px;
  border: none;
  background: var(--primary-gradient);
  color: white;
  font-size: 1.1rem;
  font-weight: 700;
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: var(--transition);
  overflow: hidden;
}

.btn-content {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.btn-content svg {
  width: 24px;
  height: 24px;
}

.btn-glow {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.3), transparent);
  opacity: 0;
  transition: var(--transition);
}

.process-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 40px rgba(102, 126, 234, 0.4);
}

.process-btn:hover .btn-glow {
  opacity: 1;
}

.process-btn:active {
  transform: translateY(-1px);
}

.process-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* Progress Container */
.progress-container {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: 24px;
  box-shadow: var(--shadow);
}

.progress-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 12px;
}

.progress-status {
  font-weight: 600;
  color: var(--text-color);
}

.progress-percent {
  font-weight: 700;
  color: var(--primary-start);
}

.progress-bar {
  width: 100%;
  height: 12px;
  background: var(--border-color);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 12px;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: var(--primary-gradient);
  border-radius: 6px;
  transition: width 0.3s ease;
  position: relative;
}

.progress-fill::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.3),
    transparent
  );
  animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

.progress-text {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-align: center;
}

/* ========================================
   How It Works Section
   ======================================== */
.how-it-works {
  margin-top: 60px;
  padding: 40px;
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
}

.how-it-works h2 {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 40px;
  text-align: center;
}

.how-it-works h2 svg {
  width: 32px;
  height: 32px;
  color: var(--primary-start);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
  margin-bottom: 32px;
}

.step-card {
  position: relative;
  text-align: center;
  padding: 32px 24px;
  background: var(--bg-color);
  border-radius: var(--border-radius);
  transition: var(--transition);
}

.step-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.step-number {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  width: 32px;
  height: 32px;
  background: var(--primary-gradient);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.step-icon {
  width: 48px;
  height: 48px;
  margin: 12px auto;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.step-icon.upload {
  background: var(--images-light);
  color: var(--images-color);
}

.step-icon.process {
  background: var(--documents-light);
  color: var(--documents-color);
}

.step-icon.download {
  background: rgba(139, 92, 246, 0.2);
  color: var(--accent-purple);
}

.step-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.step-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* Privacy Notice */
.privacy-notice {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 20px;
  background: linear-gradient(
    135deg,
    rgba(16, 185, 129, 0.15),
    rgba(5, 150, 105, 0.1)
  );
  border-radius: var(--border-radius);
  border-left: 4px solid var(--success-color);
}

/* Light mode privacy notice */
[data-theme="light"] .privacy-notice {
  background: linear-gradient(135deg, #d1fae5, #a7f3d0);
}

.privacy-notice svg {
  width: 18px;
  height: 18px;
  color: var(--success-color);
  flex-shrink: 0;
  margin-top: 2px;
}

.privacy-notice strong {
  display: block;
  color: var(--text-color);
  margin-bottom: 4px;
  font-size: 0.95rem;
}

.privacy-notice p {
  font-size: 0.85rem;
  color: var(--text-color);
  opacity: 0.85;
}

/* ========================================
   Features Section
   ======================================== */
.features {
  margin-top: 60px;
  padding: 40px 0;
}

.features h2 {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 40px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: 32px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 2px solid transparent;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.feature-card.images:hover {
  border-color: var(--images-color);
}
.feature-card.documents:hover {
  border-color: var(--documents-color);
}
.feature-card.merge:hover {
  border-color: var(--accent-purple);
}
.feature-card.platform:hover {
  border-color: var(--accent-cyan);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.feature-card.images .feature-icon {
  background: var(--images-gradient);
  color: white;
}

.feature-card.documents .feature-icon {
  background: var(--documents-gradient);
  color: white;
}

.feature-card.merge .feature-icon {
  background: linear-gradient(135deg, #8b5cf6, #7c3aed);
  color: white;
}

.feature-card.platform .feature-icon {
  background: linear-gradient(135deg, #06b6d4, #0891b2);
  color: white;
}

.feature-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ========================================
   Formats Section
   ======================================== */
.formats-section {
  margin-top: 60px;
  padding: 40px;
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
}

.formats-section h2 {
  text-align: center;
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 32px;
}

.formats-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.formats-tab {
  padding: 12px 24px;
  border: 2px solid var(--border-color);
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--border-radius-full);
  cursor: pointer;
  transition: var(--transition);
}

.formats-tab:hover {
  border-color: var(--primary-start);
  color: var(--primary-start);
}

.formats-tab.active {
  background: var(--primary-gradient);
  border-color: transparent;
  color: white;
}

.formats-panel {
  display: none;
}

.formats-panel.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.formats-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
}

.format-tag {
  padding: 8px 16px;
  background: var(--border-color);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--border-radius-full);
  transition: var(--transition);
}

.format-tag.popular {
  background: var(--primary-gradient);
  color: white;
}

.format-tag.more {
  background: var(--text-muted);
  color: white;
}

/* ========================================
   Footer
   ======================================== */
.footer {
  margin-top: 60px;
  padding: 40px 24px;
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  text-align: center;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-color);
}

.footer-logo svg {
  width: 24px;
  height: 24px;
  color: var(--primary-start);
}

.footer-brand p {
  color: var(--text-secondary);
}

.footer-brand strong {
  color: var(--primary-start);
}

.footer-links {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
}

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

.footer-links svg {
  width: 18px;
  height: 18px;
}

.footer-coffee-link {
  color: #ff5f1f !important;
  font-weight: 600;
}

.footer-coffee-link:hover {
  color: #e54500 !important;
}

.footer-privacy {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--border-color);
  border-radius: var(--border-radius-full);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-privacy svg {
  width: 18px;
  height: 18px;
  color: var(--success-color);
}

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

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 768px) {
  .app-container {
    padding: 12px;
  }

  .header-content {
    flex-direction: column;
    gap: 16px;
    padding: 16px;
  }

  .header-nav {
    width: 100%;
    justify-content: center;
  }

  .category-tabs {
    padding: 6px;
  }

  .category-tab {
    padding: 12px 8px;
    font-size: 0.75rem;
  }

  .category-tab svg {
    width: 20px;
    height: 20px;
  }

  .mode-selector {
    flex-direction: column;
  }

  .mode-btn {
    width: 100%;
    justify-content: center;
  }

  .drop-zone {
    padding: 40px 20px;
  }

  .upload-icon-wrapper {
    width: 64px;
    height: 64px;
  }

  .drop-zone h2 {
    font-size: 1.2rem;
  }

  .file-list-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .file-actions {
    width: 100%;
  }

  .action-btn {
    flex: 1;
    justify-content: center;
  }

  .options-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .how-it-works,
  .formats-section,
  .footer {
    padding: 24px 16px;
  }

  .how-it-works h2,
  .features h2,
  .formats-section h2 {
    font-size: 1.4rem;
  }

  .steps-grid {
    gap: 32px;
  }

  .privacy-notice {
    flex-direction: column;
    text-align: center;
  }

  .footer-links {
    flex-direction: column;
    gap: 12px;
  }
}

@media (max-width: 480px) {
  .logo-text h1 {
    font-size: 1.2rem;
  }

  .tagline-banner {
    flex-direction: column;
  }

  .badge {
    width: 100%;
    justify-content: center;
  }

  .format-selector {
    flex-direction: column;
    align-items: stretch;
  }

  .output-folder-selector {
    flex-direction: column;
    align-items: stretch;
  }

  .formats-tabs {
    flex-direction: column;
  }

  .formats-tab {
    width: 100%;
  }
}

/* Touch optimizations */
@media (hover: none) {
  .feature-card:hover,
  .step-card:hover,
  .file-item:hover {
    transform: none;
  }

  .process-btn:hover {
    transform: none;
    box-shadow: var(--shadow);
  }
}

/* Scrollbar styling */
.file-list::-webkit-scrollbar {
  width: 8px;
}

.file-list::-webkit-scrollbar-track {
  background: var(--bg-color);
  border-radius: 4px;
}

.file-list::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
}

.file-list::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Why Unifile Section */
.why-section {
  padding: 4rem 2rem;
  background: linear-gradient(135deg, var(--bg-color) 0%, var(--card-bg) 100%);
}

.why-content {
  max-width: 1200px;
  margin: 0 auto;
}

.why-section h2 {
  text-align: center;
  font-size: 2.5rem;
  margin-bottom: 1rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.why-section > .why-content > p {
  text-align: center;
  color: var(--text-muted);
  font-size: 1.2rem;
  margin-bottom: 3rem;
}

.why-story {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.why-story h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.problem-list,
.solution-list {
  list-style: none;
  padding: 0;
}

.problem-list li,
.solution-list li {
  padding: 1rem;
  margin-bottom: 0.75rem;
  border-radius: 12px;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1rem;
  transition: transform 0.2s ease;
}

.problem-list li:hover,
.solution-list li:hover {
  transform: translateX(5px);
}

.problem-list li {
  background: rgba(239, 68, 68, 0.1);
  border-left: 3px solid #ef4444;
  color: var(--text-color);
}

.solution-list li {
  background: rgba(16, 185, 129, 0.1);
  border-left: 3px solid #10b981;
  color: var(--text-color);
}

.why-mission {
  text-align: center;
  padding: 2.5rem;
  background: var(--card-bg);
  border-radius: 20px;
  border: 1px solid var(--border-color);
}

.why-mission h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.why-mission p {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 700px;
  margin: 0 auto;
  line-height: 1.8;
}

/* Contact Section */
.contact-section {
  padding: 4rem 2rem;
  background: var(--card-bg);
  border-top: 1px solid var(--border-color);
}

.contact-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.contact-section h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.contact-content > p {
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 2rem;
}

.contact-buttons {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.contact-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  border-radius: 12px;
  font-size: 1.1rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.contact-btn.email {
  background: var(--gradient-primary);
  color: white;
}

.contact-btn.email:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(99, 102, 241, 0.4);
}

.contact-btn.github {
  background: var(--card-bg);
  color: var(--text-color);
  border-color: var(--border-color);
}

.contact-btn.github:hover {
  background: var(--bg-color);
  border-color: var(--primary-color);
  transform: translateY(-3px);
}

.contact-btn svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* Responsive for Why & Contact sections */
@media (max-width: 768px) {
  .why-section,
  .contact-section {
    padding: 3rem 1rem;
  }

  .why-section h2,
  .contact-section h2 {
    font-size: 2rem;
  }

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

  .contact-buttons {
    flex-direction: column;
    align-items: center;
  }

  .contact-btn {
    width: 100%;
    max-width: 300px;
    justify-content: center;
  }
}