* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, blue 0%, skyblue 100%);
  min-height: 100vh;
  padding: 20px;
  color: #333;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  background: white;
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  overflow: hidden;
}

header {
  background: linear-gradient(135deg, blue 0%, skyblue 100%);
  color: white;
  padding: 40px 30px;
  text-align: center;
  position: relative;
}

header h1 {
  font-size: 2.5em;
  margin-bottom: 10px;
  font-weight: 700;
}

.subtitle {
  font-size: 1.1em;
  opacity: 0.95;
  font-weight: 300;
}

.btn-export {
  margin-top: 20px;
  padding: 10px 20px;
  background: rgba(255, 255, 255, 0.2);
  color: white;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 8px;
  font-size: 0.95em;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.btn-export:hover {
  background: rgba(255, 255, 255, 0.3);
  border-color: rgba(255, 255, 255, 0.5);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.btn-export:active {
  transform: translateY(0);
}

main {
  padding: 40px 30px;
}

.upload-section {
  margin-bottom: 30px;
}

.upload-box {
  border: 3px dashed #667eea;
  border-radius: 15px;
  padding: 60px 30px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  background: #f8f9ff;
}

.upload-box:hover {
  border-color: skyblue;
  background: #f0f2ff;
  transform: translateY(-2px);
}

.upload-box.dragover {
  border-color: skyblue;
  background: #e8ebff;
  transform: scale(1.02);
}

.upload-content svg {
  color: #667eea;
  margin-bottom: 20px;
}

.upload-content h3 {
  font-size: 1.5em;
  color: #333;
  margin-bottom: 10px;
}

.upload-content p {
  color: #666;
  margin: 5px 0;
}

.file-info {
  font-size: 0.9em;
  color: #999;
  margin-top: 10px;
}

.file-info-section {
  margin: 20px 0;
}

.fileList {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 15px;
}

.file-card {
  display: flex;
  align-items: center;
  gap: 15px;
  padding: 20px;
  background: #f8f9ff;
  border-radius: 10px;
  border: 2px solid #667eea;
}

.file-icon {
  font-size: 2em;
}

.file-details {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.file-details strong {
  color: #333;
  font-size: 1.1em;
}

.file-details span {
  color: #666;
  font-size: 0.9em;
}

.btn-remove-small {
  background: #ff4757;
  color: white;
  border: none;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  font-size: 1.3em;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
  flex-shrink: 0;
}

.btn-remove-small:hover {
  background: #ff3838;
  transform: scale(1.1);
}

.btn-remove {
  background: #ff4757;
  color: white;
  border: none;
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 1em;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  display: block;
  margin: 10px auto 0;
  width: fit-content;
}

.btn-remove:hover {
  background: #ff3838;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(255, 71, 87, 0.3);
}

.btn-process {
  width: 100%;
  padding: 18px;
  background: linear-gradient(135deg, blue 0%, skyblue 100%);
  color: white;
  border: none;
  border-radius: 10px;
  font-size: 1.2em;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.btn-process:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
}

.btn-process:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-spinner {
  animation: spin 1s linear infinite;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.result-section,
.error-section {
  margin: 30px 0;
}

.result-card {
  padding: 30px;
  border-radius: 15px;
  display: flex;
  gap: 20px;
  align-items: flex-start;
}

.result-card.success {
  background: #d4edda;
  border: 2px solid #28a745;
}

.result-card.error {
  background: #f8d7da;
  border: 2px solid #dc3545;
}

.result-icon {
  font-size: 3em;
  flex-shrink: 0;
}

.result-content {
  flex: 1;
}

.result-content h3 {
  margin-bottom: 10px;
  color: #333;
}

.result-content p {
  color: #666;
  margin-bottom: 15px;
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: #28a745;
  color: white;
  text-decoration: none;
  border-radius: 8px;
  font-weight: 600;
  transition: all 0.2s ease;
}

.btn-download:hover {
  background: #218838;
  transform: translateY(-2px);
}

.progress-section {
  margin: 30px 0;
}

.progress-bar {
  width: 100%;
  height: 30px;
  background: #e0e0e0;
  border-radius: 15px;
  overflow: hidden;
  margin-bottom: 15px;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
  width: 0%;
  transition: width 0.3s ease;
  border-radius: 15px;
}

.progress-text {
  text-align: center;
  color: #666;
  font-weight: 500;
}

footer {
  padding: 30px;
  text-align: center;
  background: #f8f9fa;
  color: #666;
  border-top: 1px solid #e0e0e0;
}

footer p {
  font-size: 0.95em;
}

/* Responsive */
@media (max-width: 600px) {
  header h1 {
    font-size: 2em;
  }

  main {
    padding: 30px 20px;
  }

  .upload-box {
    padding: 40px 20px;
  }

  .result-card {
    flex-direction: column;
    text-align: center;
  }
}