:root {
  --primary-color: #4caf50;
  --danger-color: #f44336;
  --warning-color: #ff9800;
  --light-bg: #f9f9f9;
  --dark-text: #333;
  --light-text: #fff;
  --border-radius: 4px;
  --box-shadow: 0 2px 8px rgba(0,0,0,0.15);
  --transition: all 0.3s ease;
}

/* Add an extra comment to ensure file is updated */
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--light-bg);
  color: var(--dark-text);
  line-height: 1.6;
  margin: 0;
  padding: 0;
}

/* Back link styling */
.back-link {
  display: inline-block;
  color: #666;
  text-decoration: none;
  font-size: 0.9rem;
  margin-top: 5px;
  transition: color 0.2s ease;
}

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

.back-link i {
  margin-right: 5px;
}

.container {
  max-width: 800px;
  margin: 30px auto;
  background: #fff;
  padding: 25px;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

header {
  margin-bottom: 20px;
  border-bottom: 1px solid #eee;
  padding-bottom: 10px;
}

h1 {
  color: var(--primary-color);
  margin-bottom: 10px;
}

.description {
  color: #666;
  margin-top: 0;
}

label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
}

.input-section {
  margin-bottom: 20px;
}

textarea {
  width: 100%;
  height: 120px;
  margin-bottom: 8px;
  padding: 12px;
  font-size: 1rem;
  border: 1px solid #ddd;
  border-radius: var(--border-radius);
  transition: var(--transition);
  resize: vertical;
}

textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.2);
}

.help-text {
  color: #666;
  font-size: 0.9rem;
  margin-top: 0;
}

.buttons {
  margin: 20px 0;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

button {
  padding: 10px 16px;
  font-size: 0.95rem;
  border-radius: var(--border-radius);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  transition: var(--transition);
  background: #e9e9e9;
}

button i {
  margin-right: 6px;
}

button:hover {
  background: #ddd;
}

button.primary {
  background-color: var(--primary-color);
  color: var(--light-text);
}

button.primary:hover {
  background-color: #3d8b40;
}

#copyValidBtn:hover {
  background-color: #e0e0e0;
}

#clearBtn:hover {
  background-color: #ffcdd2;
}

.examples {
  background-color: #f5f5f5;
  padding: 15px;
  border-radius: var(--border-radius);
  margin-bottom: 20px;
}

.examples h2 {
  margin-top: 0;
  font-size: 1.2rem;
}

.examples code {
  background: #e0e0e0;
  padding: 2px 4px;
  border-radius: 3px;
  font-size: 0.9rem;
  word-break: break-all;
}

#results {
  list-style: none;
  padding: 0;
}

#results li {
  padding: 8px 12px;
  margin-bottom: 6px;
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  background: #f5f5f5;
  word-break: break-all;
  transition: var(--transition);
}

#results li.valid {
  background-color: rgba(76, 175, 80, 0.1);
  border-left: 4px solid var(--primary-color);
  color: #2e7d32;
}

#results li.invalid {
  background-color: rgba(244, 67, 54, 0.1);
  border-left: 4px solid var(--danger-color);
  color: #c62828;
}

#results li span {
  margin-right: 8px;
  flex-shrink: 0;
}

#results li .reason {
  font-size: 0.8rem;
  margin-left: 10px;
  padding: 2px 6px;
  background: rgba(0,0,0,0.08);
  border-radius: 3px;
}

.summary {
  background-color: #e8f5e9;
  padding: 10px 15px;
  border-radius: var(--border-radius);
  margin-bottom: 20px;
  font-weight: 500;
}

.summary #valid-count {
  color: var(--primary-color);
  font-weight: bold;
}

.summary #invalid-count {
  color: var(--danger-color);
  font-weight: bold;
}

.hidden {
  display: none;
}

.loader {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 20px 0;
}

.spinner {
  border: 4px solid rgba(0,0,0,0.1);
  border-left: 4px solid var(--primary-color);
  border-radius: 50%;
  width: 30px;
  height: 30px;
  animation: spin 1s linear infinite;
}

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

.results-container {
  margin-top: 20px;
}

.results-container h2 {
  font-size: 1.2rem;
  color: #555;
}

@media (max-width: 600px) {
  .container {
    margin: 10px;
    padding: 15px;
  }
  
  .buttons {
    flex-direction: column;
  }
  
  button {
    width: 100%;
  }
}

.copied-feedback {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: var(--primary-color);
  color: white;
  padding: 10px 20px;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.copied-feedback.show {
  opacity: 1;
}