* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: #f5f5f5;
  color: #333;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 40px 16px;
}

.container {
  width: 100%;
  max-width: 480px;
}

.lang-switcher {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  margin-bottom: 16px;
}

.lang-btn {
  padding: 6px 12px;
  border: 1px solid #ddd;
  border-radius: 4px;
  background: #fff;
  color: #666;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.15s ease;
}

.lang-btn:hover {
  border-color: #0070f3;
  color: #0070f3;
}

.lang-btn.active {
  background: #0070f3;
  border-color: #0070f3;
  color: #fff;
}

.title {
  margin: 0 0 8px;
  font-size: 24px;
  font-weight: 600;
  color: #1a1a1a;
}

.subtitle {
  margin: 0 0 24px;
  color: #666;
  font-size: 14px;
  line-height: 1.5;
}

.card {
  background: #fff;
  border: 1px solid #e0e0e0;
  border-radius: 8px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.btn {
  width: 100%;
  margin-top: 20px;
  border: none;
  border-radius: 6px;
  padding: 14px 16px;
  background: #0070f3;
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease;
  text-decoration: none;
  display: inline-block;
  text-align: center;
}

.btn:hover {
  background: #005bb5;
}

.btn:disabled {
  background: #ccc;
  cursor: not-allowed;
}

.message {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: 6px;
  border: 1px solid #f5c6cb;
  background: #f8d7da;
  color: #721c24;
  font-size: 14px;
  display: none;
  line-height: 1.4;
}

.hint {
  margin-top: 20px;
  color: #888;
  font-size: 13px;
  line-height: 1.5;
  text-align: center;
}

code {
  background: #eee;
  border: 1px solid #ddd;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: "SF Mono", Monaco, Consolas, monospace;
  font-size: 12px;
}

.success-text {
  margin: 0 0 12px;
  color: #28a745;
  font-weight: 600;
}

.success-note {
  margin: 0 0 20px;
  color: #666;
  font-size: 14px;
}