:root {
  --bg-color: #ffffff;
  --text-color: #1a202c;
  --card-bg: #f7fafc;
  --border-color: #e2e8f0;
}

.dark {
  --bg-color: #1a202c;
  --text-color: #f7fafc;
  --card-bg: #2d3748;
  --border-color: #4a5568;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s, color 0.3s;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem;
}

header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1rem;
  margin-bottom: 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
}

.language-controls {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

select, button {
  padding: 0.5rem 1rem;
  border-radius: 0.375rem;
  border: 1px solid var(--border-color);
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.2s;
}

textarea {
  width: 100%;
  min-height: 200px;
  padding: 1rem;
  margin-bottom: 1.5rem;
  border: 1px solid var(--border-color);
  border-radius: 0.375rem;
  resize: vertical;
  font-size: 1rem;
  background-color: var(--card-bg);
  transition: background-color 0.3s;
}

.relative {
  position: relative;
}

.actions {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  display: flex;
  gap: 0.5rem;
}

.btn {
  border: none;
  border-radius: 0.375rem;
  cursor: pointer;
  transition: background-color 0.2s;
}

.btn-copy {
  background-color: #4299e1;
  color: white;
}

.btn-copy:hover {
  background-color: #3182ce;
}

.btn-clear {
  background-color: #cbd5e0;
  color: #1a202c;
}

.btn-clear:hover {
  background-color: #a0aec0;
}

.btn-sample {
  background-color: #8b5cf6;
  color: white;
}

.btn-sample:hover {
  background-color: #6d28d9;
}

.count-display {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.count-card {
  background-color: var(--card-bg);
  padding: 1.5rem;
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  transition: background-color 0.3s;
}

.count-title {
  font-size: 0.875rem;
  color: #718096;
}

.count-value {
  font-size: 2rem;
  font-weight: 600;
  margin-top: 0.25rem;
}

.about-section,
.faq-section {
  background-color: var(--card-bg);
  padding: 1.5rem;
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  margin-bottom: 2rem;
  transition: background-color 0.3s;
}

.faq-item {
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 0;
}

.faq-item:last-child {
  border-bottom: none;
}

.faq-question {
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-answer {
  margin-top: 0.5rem;
  display: none;
}

.faq-item.open .faq-answer {
  display: block;
}

.faq-arrow {
  transition: transform 0.2s;
}

footer {
  text-align: center;
  padding: 2rem 1rem;
  border-top: 1px solid var(--border-color);
  margin-top: 2rem;
  font-size: 0.875rem;
  color: #718096;
  transition: color 0.3s;
}

.hidden {
  display: none;
}