/* CSS Variables for Theme Management */
:root {
  --primary-color: #05386B;
  --secondary-color: #379683;
  --accent-color: #5CDB95;
  --light-accent: #8EE4AF;
  --background-color: #EDF5E1;
  --text-primary: #05386B;
  --text-secondary: #379683;
  --white: #ffffff;
  --gray-100: #f8f9fa;
  --gray-200: #e9ecef;
  --gray-300: #dee2e6;
  --gray-400: #ced4da;
  --gray-500: #adb5bd;
  --gray-600: #6c757d;
  --gray-700: #495057;
  --gray-800: #343a40;
  --gray-900: #212529;
  --success: #28a745;
  --warning: #ffc107;
  --error: #dc3545;
  --shadow-sm: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
  --shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 1rem 3rem rgba(0, 0, 0, 0.175);
  --border-radius: 0.5rem;
  --border-radius-lg: 1rem;
  --transition: all 0.3s ease;
}

/* Dark Theme Variables */
[data-theme="dark"] {
  --background-color: #0a0e1a;
  --text-primary: #EDF5E1;
  --text-secondary: #8EE4AF;
  --white: #1a1f2e;
  --gray-100: #1a1f2e;
  --gray-200: #252a3a;
  --gray-300: #2f3447;
  --gray-400: #3a3f54;
  --gray-500: #454a61;
  --gray-600: #50556e;
  --gray-700: #5b607b;
  --gray-800: #666b88;
  --gray-900: #717695;
}

/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--background-color) 0%, var(--light-accent) 100%);
  min-height: 100vh;
  transition: var(--transition);
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* App Container */
.app-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: var(--white);
  padding: 1rem 0;
  box-shadow: var(--shadow);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 2rem;
  font-weight: 700;
  margin: 0;
  background: linear-gradient(45deg, var(--accent-color), var(--light-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.theme-toggle {
  position: relative;
}

.theme-btn {
  background: rgba(255, 255, 255, 0.1);
  border: 2px solid rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  width: 3rem;
  height: 3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
  backdrop-filter: blur(10px);
}

.theme-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: scale(1.05);
}

.theme-icon {
  font-size: 1.2rem;
}

/* Main Content */
.main-content {
  flex: 1;
  padding: 2rem 0;
}

/* Upload Section */
.upload-section {
  margin-bottom: 2rem;
}

.upload-area {
  border: 2px dashed var(--accent-color);
  border-radius: var(--border-radius-lg);
  padding: 3rem 2rem;
  text-align: center;
  background: linear-gradient(135deg, var(--white) 0%, rgba(92, 219, 149, 0.05) 100%);
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.upload-area::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg, transparent, rgba(92, 219, 149, 0.1), transparent);
  transform: rotate(-45deg);
  transition: var(--transition);
  opacity: 0;
}

.upload-area:hover::before {
  opacity: 1;
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% { transform: translateX(-100%) translateY(-100%) rotate(-45deg); }
  100% { transform: translateX(100%) translateY(100%) rotate(-45deg); }
}

.upload-area:hover {
  border-color: var(--secondary-color);
  background: linear-gradient(135deg, var(--white) 0%, rgba(92, 219, 149, 0.1) 100%);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.upload-area.dragover {
  border-color: var(--primary-color);
  background: linear-gradient(135deg, rgba(92, 219, 149, 0.1) 0%, rgba(92, 219, 149, 0.2) 100%);
  transform: scale(1.02);
}

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

.upload-icon {
  margin-bottom: 1rem;
  color: var(--accent-color);
}

.upload-content h2 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-weight: 600;
}

.upload-content p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

.supported-formats {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem;
}

.format-tag {
  background: linear-gradient(135deg, var(--accent-color) 0%, var(--light-accent) 100%);
  color: var(--primary-color);
  padding: 0.25rem 0.75rem;
  border-radius: 1rem;
  font-size: 0.875rem;
  font-weight: 500;
  box-shadow: var(--shadow-sm);
}

#fileInput {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

/* Size Converter Section */
.size-converter-section {
  margin-bottom: 2rem;
}

.converter-card {
  background: var(--white);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--gray-200);
}

.converter-card h3 {
  margin-bottom: 1.5rem;
  color: var(--text-primary);
  text-align: center;
  font-weight: 600;
}

.size-converter {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.input-group {
  display: flex;
  gap: 0.5rem;
  min-width: 200px;
}

.input-group input,
.input-group select {
  padding: 0.75rem;
  border: 2px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: var(--transition);
  background: var(--white);
  color: var(--text-primary);
}

.input-group input:focus,
.input-group select:focus {
  outline: none;
  border-color: var(--accent-color);
  box-shadow: 0 0 0 3px rgba(92, 219, 149, 0.1);
}

.input-group input {
  flex: 2;
}

.input-group select {
  flex: 1;
}

.convert-arrow {
  font-size: 1.5rem;
  color: var(--accent-color);
  font-weight: bold;
}

/* Files Section */
.files-section {
  margin-bottom: 2rem;
}

.files-section h3 {
  margin-bottom: 1.5rem;
  color: var(--text-primary);
  font-weight: 600;
}

.files-list {
  display: grid;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.file-item {
  background: var(--white);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--gray-200);
  transition: var(--transition);
}

.file-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.file-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.file-info h4 {
  margin-bottom: 0.25rem;
  color: var(--text-primary);
  font-weight: 500;
  word-break: break-all;
}

.file-meta {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.file-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.file-controls {
  display: grid;
  gap: 1rem;
  margin-top: 1rem;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.control-group label {
  font-weight: 500;
  color: var(--text-primary);
  min-width: 120px;
}

.control-group select,
.control-group input[type="range"] {
  flex: 1;
  min-width: 150px;
}

.control-group select {
  padding: 0.5rem;
  border: 2px solid var(--gray-300);
  border-radius: var(--border-radius);
  background: var(--white);
  color: var(--text-primary);
}

.control-group input[type="range"] {
  -webkit-appearance: none;
  height: 6px;
  border-radius: 3px;
  background: var(--gray-300);
  outline: none;
}

.control-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent-color);
  cursor: pointer;
}

.control-group input[type="range"]::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent-color);
  cursor: pointer;
  border: none;
}

.quality-value {
  font-weight: 600;
  color: var(--accent-color);
  min-width: 40px;
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-width: 120px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-color) 0%, var(--secondary-color) 100%);
  color: var(--white);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.btn-secondary {
  background: var(--gray-200);
  color: var(--text-primary);
  border: 2px solid var(--gray-300);
}

.btn-secondary:hover {
  background: var(--gray-300);
  transform: translateY(-2px);
}

.btn-success {
  background: linear-gradient(135deg, var(--success) 0%, #20c997 100%);
  color: var(--white);
}

.btn-success:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.btn-warning {
  background: linear-gradient(135deg, var(--warning) 0%, #fd7e14 100%);
  color: var(--white);
}

.btn-warning:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.btn-danger {
  background: linear-gradient(135deg, var(--error) 0%, #e74c3c 100%);
  color: var(--white);
}

.btn-danger:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

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

.btn-small {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
  min-width: 80px;
}

/* Batch Actions */
.batch-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Progress Section */
.progress-section {
  margin-bottom: 2rem;
}

.progress-container {
  background: var(--white);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--gray-200);
  text-align: center;
}

.progress-container h4 {
  margin-bottom: 1rem;
  color: var(--text-primary);
  font-weight: 600;
}

.progress-bar {
  width: 100%;
  height: 12px;
  background: var(--gray-200);
  border-radius: 6px;
  overflow: hidden;
  margin-bottom: 1rem;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(135deg, var(--accent-color) 0%, var(--secondary-color) 100%);
  width: 0%;
  transition: width 0.3s ease;
  border-radius: 6px;
}

.progress-text {
  font-weight: 600;
  color: var(--text-primary);
  font-size: 1.125rem;
}

/* Results Section */
.results-section {
  margin-bottom: 2rem;
}

.results-section h3 {
  margin-bottom: 1.5rem;
  color: var(--text-primary);
  font-weight: 600;
}

.results-list {
  display: grid;
  gap: 1rem;
}

.result-item {
  background: var(--white);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--gray-200);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.result-info h4 {
  margin-bottom: 0.25rem;
  color: var(--text-primary);
  font-weight: 500;
}

.result-meta {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* Footer */
.footer {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: var(--white);
  text-align: center;
  padding: 1.5rem 0;
  margin-top: auto;
}

.footer p {
  margin: 0;
  font-size: 0.875rem;
  opacity: 0.9;
}

/* Loading Overlay */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
  display: none;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  z-index: 9999;
  backdrop-filter: blur(5px);
}

.loading-overlay.show {
  display: flex;
}

.loading-spinner {
  width: 60px;
  height: 60px;
  border: 4px solid rgba(92, 219, 149, 0.3);
  border-top: 4px solid var(--accent-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: 1rem;
}

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

.loading-overlay p {
  color: var(--white);
  font-size: 1.125rem;
  font-weight: 500;
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  top: 2rem;
  right: 2rem;
  z-index: 10000;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.toast {
  background: var(--white);
  border-radius: var(--border-radius);
  padding: 1rem 1.5rem;
  box-shadow: var(--shadow-lg);
  border-left: 4px solid var(--accent-color);
  min-width: 300px;
  max-width: 400px;
  animation: slideIn 0.3s ease;
  position: relative;
  overflow: hidden;
}

.toast.success {
  border-left-color: var(--success);
}

.toast.error {
  border-left-color: var(--error);
}

.toast.warning {
  border-left-color: var(--warning);
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

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

.toast-icon {
  font-size: 1.25rem;
}

.toast-message {
  flex: 1;
  color: var(--text-primary);
  font-weight: 500;
}

.toast-close {
  background: none;
  border: none;
  font-size: 1.25rem;
  cursor: pointer;
  color: var(--text-secondary);
  padding: 0;
  margin-left: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: 0 0.75rem;
  }

  .header-content {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }

  .logo {
    font-size: 1.75rem;
  }

  .upload-area {
    padding: 2rem 1rem;
  }

  .upload-content h2 {
    font-size: 1.25rem;
  }

  .supported-formats {
    flex-direction: column;
    align-items: center;
  }

  .size-converter {
    flex-direction: column;
    align-items: stretch;
  }

  .input-group {
    min-width: auto;
  }

  .convert-arrow {
    align-self: center;
    transform: rotate(90deg);
  }

  .file-header {
    flex-direction: column;
    gap: 1rem;
  }

  .file-actions {
    width: 100%;
    justify-content: flex-start;
  }

  .control-group {
    flex-direction: column;
    align-items: flex-start;
  }

  .control-group label {
    min-width: auto;
  }

  .control-group select,
  .control-group input[type="range"] {
    width: 100%;
    min-width: auto;
  }

  .batch-actions {
    flex-direction: column;
    align-items: center;
  }

  .result-item {
    flex-direction: column;
    align-items: flex-start;
  }

  .toast-container {
    top: 1rem;
    right: 1rem;
    left: 1rem;
  }

  .toast {
    min-width: auto;
    max-width: none;
  }
}

@media (max-width: 480px) {
  .main-content {
    padding: 1rem 0;
  }

  .upload-area {
    padding: 1.5rem 0.75rem;
  }

  .converter-card,
  .progress-container {
    padding: 1.5rem;
  }

  .file-item {
    padding: 1rem;
  }

  .btn {
    padding: 0.625rem 1.25rem;
    font-size: 0.875rem;
  }

  .footer {
    padding: 1rem 0;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --shadow-sm: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.3);
    --shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 1rem 3rem rgba(0, 0, 0, 0.5);
  }

  .upload-area {
    border-width: 3px;
  }

  .btn {
    border: 2px solid transparent;
  }

  .btn-primary {
    border-color: var(--primary-color);
  }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .upload-area::before {
    display: none;
  }
}

/* Print styles */
@media print {
  .header,
  .footer,
  .upload-section,
  .batch-actions,
  .progress-section,
  .loading-overlay,
  .toast-container {
    display: none !important;
  }

  .main-content {
    padding: 0;
  }

  .files-section,
  .results-section {
    break-inside: avoid;
  }
}