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

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
    Cantarell, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.container {
  background: white;
  border-radius: 20px;
  padding: 40px;
  max-width: 600px;
  width: 100%;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

h1 {
  color: #333;
  margin-bottom: 10px;
  font-size: 2em;
}

.subtitle {
  color: #666;
  margin-bottom: 30px;
}

.upload-area {
  border: 3px dashed #667eea;
  border-radius: 10px;
  padding: 40px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s;
  margin-bottom: 20px;
}

.upload-area:hover {
  border-color: #764ba2;
  background: #f8f9ff;
}

.upload-area.dragging {
  border-color: #764ba2;
  background: #f0f1ff;
}

.upload-icon {
  font-size: 48px;
  margin-bottom: 10px;
}

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

.file-info {
  margin-top: 15px;
  padding: 15px;
  background: #f0f1ff;
  border-radius: 8px;
  display: none;
}

.file-info.show {
  display: block;
}

button {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  padding: 15px 40px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  width: 100%;
  transition: transform 0.2s;
}

button:hover {
  transform: translateY(-2px);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.message {
  margin-top: 20px;
  padding: 15px;
  border-radius: 8px;
  display: none;
}

.message.show {
  display: block;
}

.message.success {
  background: #d4edda;
  color: #155724;
  border: 1px solid #c3e6cb;
}

.message.error {
  background: #f8d7da;
  color: #721c24;
  border: 1px solid #f5c6cb;
}

.nav-link {
  display: inline-block;
  margin-top: 20px;
  color: #667eea;
  text-decoration: none;
  font-weight: 600;
}

.nav-link:hover {
  text-decoration: underline;
}

.supported-formats {
  margin-top: 15px;
  color: #666;
  font-size: 14px;
}

.spinner {
  border: 3px solid #f3f3f3;
  border-top: 3px solid #667eea;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 1s linear infinite;
  margin: 20px auto;
  display: none;
}

.spinner.show {
  display: block;
}

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