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

:root {
  --primary-color: #6366f1;
  --primary-dark: #4f46e5;
  --secondary-color: #10b981;
  --accent-color: #f59e0b;
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-accent: #f3f4f6;
  --border-color: #e5e7eb;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
}

/* Modern Header */
.modern-header {
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.95);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
}

.nav-menu {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: width 0.2s ease;
}

.nav-link:hover::after {
  width: 100%;
}

/* Hero Section */
.hero {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: white;
  padding: 6rem 2rem;
  text-align: center;
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 800;
  margin-bottom: 1.5rem;
  line-height: 1.2;
}

.hero p {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.9;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* Modern Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s ease;
  border: none;
  cursor: pointer;
  font-size: 1rem;
}

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

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

.btn-secondary {
  background: transparent;
  color: white;
  border: 2px solid white;
}

.btn-secondary:hover {
  background: white;
  color: var(--primary-color);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-outline:hover {
  background: var(--primary-color);
  color: white;
  transform: translateY(-2px);
}

/* Features Section */
.features {
  padding: 5rem 2rem;
  background: var(--bg-secondary);
}

.features-container {
  max-width: 1200px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.feature-card {
  background: var(--bg-primary);
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  border: 1px solid var(--border-color);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

.feature-icon {
  width: 4rem;
  height: 4rem;
  background: var(--primary-color);
  border-radius: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  color: white;
  font-size: 1.5rem;
}

.feature-card h3 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.feature-card p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Conversion Sections */
.conversion-section {
  padding: 5rem 2rem;
  background: var(--bg-primary);
}

.conversion-container {
  max-width: 1000px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.section-header p {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.conversion-form {
  background: var(--bg-secondary);
  padding: 2.5rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-primary);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid var(--border-color);
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: border-color 0.2s ease;
  background: var(--bg-primary);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgb(99 102 241 / 0.1);
}

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

/* Enhanced File Upload Styling */
.file-upload {
  border: 2px dashed var(--border-color);
  border-radius: 0.5rem;
  padding: 2rem;
  text-align: center;
  background: var(--bg-accent);
  transition: all 0.2s ease;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.file-upload:hover {
  border-color: var(--primary-color);
  background: var(--bg-secondary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.file-upload.highlight {
  border-color: var(--primary-color);
  background: var(--primary-color);
  color: white;
}

.file-upload.highlight .file-upload-label {
  color: white;
}

.file-upload.highlight .file-upload-label strong {
  color: white;
}

.file-upload input[type="file"] {
  display: none;
}

.file-upload-label {
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.file-upload-label strong {
  color: var(--primary-color);
  font-weight: 600;
}

.file-upload-label i {
  margin-bottom: 1rem;
  opacity: 0.7;
}

.file-upload-label small {
  display: block;
  margin-top: 0.5rem;
  opacity: 0.6;
}

/* Results Section */
.results {
  margin-top: 2rem;
  padding: 1.5rem;
  background: var(--bg-primary);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
}

.result-text {
  background: var(--bg-accent);
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 1rem;
  white-space: pre-wrap;
  line-height: 1.6;
}

.audio-player {
  margin: 1rem 0;
}

.audio-player audio {
  width: 100%;
  border-radius: 0.5rem;
}

.download-links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* Steps Section */
.steps {
  padding: 5rem 2rem;
  background: var(--bg-secondary);
}

.steps-container {
  max-width: 1200px;
  margin: 0 auto;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.step-card {
  background: var(--bg-primary);
  padding: 2rem;
  border-radius: 1rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  position: relative;
}

.step-number {
  position: absolute;
  top: -1rem;
  left: 50%;
  transform: translateX(-50%);
  width: 3rem;
  height: 3rem;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.25rem;
}

.step-card h3 {
  margin: 1rem 0;
  color: var(--text-primary);
}

.step-card p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Testimonials */
.testimonials {
  padding: 5rem 2rem;
  background: var(--bg-primary);
}

.testimonials-container {
  max-width: 1200px;
  margin: 0 auto;
}

.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.testimonial-card {
  background: var(--bg-secondary);
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.testimonial-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.testimonial-avatar {
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  background: var(--primary-color);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
}

.testimonial-info h4 {
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.testimonial-info span {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.testimonial-text {
  color: var(--text-secondary);
  line-height: 1.6;
  font-style: italic;
}

/* Footer */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 3rem 2rem 1rem;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-section h3 {
  margin-bottom: 1rem;
  color: var(--bg-primary);
}

.footer-section p,
.footer-section a {
  color: var(--bg-secondary);
  text-decoration: none;
  line-height: 1.6;
}

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

.footer-bottom {
  border-top: 1px solid var(--text-secondary);
  padding-top: 1rem;
  text-align: center;
  color: var(--bg-secondary);
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .nav-menu {
    display: none;
  }
  
  .conversion-form {
    padding: 1.5rem;
  }
  
  .features-grid,
  .steps-grid,
  .testimonials-grid {
    grid-template-columns: 1fr;
  }
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

/* Loading States */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid var(--border-color);
  border-radius: 50%;
  border-top-color: var(--primary-color);
  animation: spin 1s ease-in-out infinite;
}

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

/* Success/Error States */
.success-message {
  background: var(--secondary-color);
  color: white;
  padding: 1rem;
  border-radius: 0.5rem;
  margin: 1rem 0;
}

.error-message {
  background: #ef4444;
  color: white;
  padding: 1rem;
  border-radius: 0.5rem;
  margin: 1rem 0;
}

/* Enhanced Mobile Responsiveness */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .nav-menu {
    display: none;
  }
  
  .conversion-form {
    padding: 1.5rem;
  }
  
  .features-grid,
  .steps-grid,
  .testimonials-grid {
    grid-template-columns: 1fr;
  }
  
  .header-container {
    padding: 1rem;
  }
  
  .hero {
    padding: 4rem 1rem;
  }
  
  .conversion-section {
    padding: 3rem 1rem;
  }
  
  .features {
    padding: 3rem 1rem;
  }
  
  .steps {
    padding: 3rem 1rem;
  }
  
  .testimonials {
    padding: 3rem 1rem;
  }
  
  .footer {
    padding: 2rem 1rem 1rem;
  }
  
  .section-header h2 {
    font-size: 2rem;
  }
  
  .file-upload {
    padding: 1.5rem;
  }
  
  .file-upload-label {
    font-size: 0.9rem;
  }
  
  .file-upload-label i {
    font-size: 1.5rem;
  }
  
  .language-switcher {
    margin-left: auto;
  }
  
  .lang-btn {
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
    min-width: 2.5rem;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 2rem;
  }
  
  .hero p {
    font-size: 1.1rem;
  }
  
  .section-header h2 {
    font-size: 1.75rem;
  }
  
  .conversion-form {
    padding: 1rem;
  }
  
  .btn {
    padding: 0.6rem 1.2rem;
    font-size: 0.9rem;
  }
  
  .feature-card,
  .step-card,
  .testimonial-card {
    padding: 1.5rem;
  }
}

/* Enhanced Button States */
.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
}

.btn:disabled:hover {
  transform: none !important;
  box-shadow: none !important;
}

/* Enhanced Form States */
.form-input:invalid,
.form-select:invalid,
.form-textarea:invalid {
  border-color: #ef4444;
}

.form-input:invalid:focus,
.form-select:invalid:focus,
.form-textarea:invalid:focus {
  box-shadow: 0 0 0 3px rgb(239 68 68 / 0.1);
}

/* Enhanced Loading States */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid var(--border-color);
  border-radius: 50%;
  border-top-color: var(--primary-color);
  animation: spin 1s ease-in-out infinite;
  margin-right: 0.5rem;
}

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

/* Enhanced Success/Error States */
.success-message {
  background: var(--secondary-color);
  color: white;
  padding: 1rem;
  border-radius: 0.5rem;
  margin: 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.success-message::before {
  content: "✓";
  font-weight: bold;
}

.error-message {
  background: #ef4444;
  color: white;
  padding: 1rem;
  border-radius: 0.5rem;
  margin: 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.error-message::before {
  content: "✗";
  font-weight: bold;
}

/* Enhanced Results Section */
.results {
  margin-top: 2rem;
  padding: 1.5rem;
  background: var(--bg-primary);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.results h3 {
  color: var(--text-primary);
  margin-bottom: 1rem;
  font-size: 1.25rem;
}

.result-text {
  background: var(--bg-accent);
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 1rem;
  white-space: pre-wrap;
  line-height: 1.6;
  border-left: 4px solid var(--primary-color);
  font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
  font-size: 0.9rem;
}

.audio-player {
  margin: 1rem 0;
  padding: 1rem;
  background: var(--bg-secondary);
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
}

.audio-player h4 {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  font-size: 1rem;
}

.audio-player audio {
  width: 100%;
  border-radius: 0.5rem;
  height: 40px;
}

.download-links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

.download-links .btn {
  flex: 1;
  min-width: 200px;
  justify-content: center;
}

/* Enhanced Navigation */
.nav-menu {
  display: flex;
  gap: 2rem;
  list-style: none;
  align-items: center;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s ease;
  position: relative;
  padding: 0.5rem 0;
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: width 0.2s ease;
}

.nav-link:hover::after {
  width: 100%;
}

/* Language Switcher */
.language-switcher {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.lang-btn {
  background: var(--bg-secondary);
  border: 2px solid var(--border-color);
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
  border-radius: 0.5rem;
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  transition: all 0.2s ease;
  min-width: 3rem;
  text-align: center;
}

.lang-btn:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
  background: var(--bg-primary);
}

.lang-btn.active {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
}

.lang-btn.active:hover {
  background: var(--primary-dark);
}

/* Enhanced Logo */
.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.2s ease;
}

.logo:hover {
  transform: scale(1.05);
}

.logo i {
  font-size: 1.75rem;
}

/* Enhanced Feature Cards */
.feature-card {
  background: var(--bg-primary);
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  border: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

/* Enhanced Step Cards */
.step-card {
  background: var(--bg-primary);
  padding: 2rem;
  border-radius: 1rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  position: relative;
  transition: all 0.3s ease;
}

.step-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.step-number {
  position: absolute;
  top: -1rem;
  left: 50%;
  transform: translateX(-50%);
  width: 3rem;
  height: 3rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.25rem;
  box-shadow: var(--shadow-md);
}

/* Enhanced Testimonial Cards */
.testimonial-card {
  background: var(--bg-secondary);
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: all 0.3s ease;
}

.testimonial-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.testimonial-avatar {
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  box-shadow: var(--shadow-sm);
}

/* Enhanced Footer */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 3rem 2rem 1rem;
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.footer-section a {
  color: var(--bg-secondary);
  text-decoration: none;
  line-height: 1.6;
  transition: color 0.2s ease;
  display: inline-block;
  margin-bottom: 0.5rem;
}

.footer-section a:hover {
  color: var(--primary-color);
  transform: translateX(5px);
}

/* Enhanced Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

.slide-in-left {
  animation: slideInLeft 0.6s ease-out;
}

.slide-in-right {
  animation: slideInRight 0.6s ease-out;
}

/* Enhanced Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

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

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-dark);
}

/* Enhanced Focus States */
*:focus {
  outline: none;
}

.btn:focus,
.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  box-shadow: 0 0 0 3px rgb(99 102 241 / 0.1);
}

/* Enhanced Selection */
::selection {
  background: var(--primary-color);
  color: white;
}

::-moz-selection {
  background: var(--primary-color);
  color: white;
}