/* Base variables & reset */

:root {
  --color-bg: #f8f9fa;
  --color-surface: #ffffff;
  --color-surface-alt: #f8f9ff;
  --color-primary: #007bff;
  --color-primary-dark: #0056b3;
  --color-border: #e1e8ef;
  --color-text: #333333;
  --color-text-soft: #666666;
  --color-muted: #9ca3af;
  --shadow-soft: 0 4px 6px rgba(0, 0, 0, 0.08);
  --radius-card: 12px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
}

/* Layout */

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.5rem 1rem 2.5rem;
}

.card {
  background: var(--color-surface);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-soft);
  padding: 1.5rem 1.25rem;
  margin-bottom: 1.5rem;
  border: 1px solid var(--color-border);
}

/* Header & nav */

.site-header {
  background: var(--color-primary);
  color: #ffffff;
  padding: 1.5rem 1rem 1rem;
  text-align: center;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  justify-content: space-between;
  text-align: center;
}

.site-header h1 {
  margin: 0 0 0.3rem;
  font-size: 1.9rem;
}

.site-header .intro {
  margin: 0;
  font-size: 0.98rem;
  opacity: 0.95;
  text-align: center;
}

.main-nav {
  max-width: 1200px;
  margin: 0.5rem auto 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  padding: 0 1rem 1rem;
}

.main-nav a {
  color: #e0f2ff;
  text-decoration: none;
  font-size: 0.92rem;
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.main-nav a:hover {
  background: rgba(255, 255, 255, 0.16);
}

/* Typography */

.section-title {
  text-align: center;
  margin: 0 0 1rem;
  font-size: 1.6rem;
  color: var(--color-primary);
  position: relative;
}

.section-title::after {
  content: "";
  position: absolute;
  width: 70px;
  height: 3px;
  background: var(--color-primary);
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 2px;
}

.section-subtitle {
  text-align: center;
  margin: 0.75rem auto 1.25rem;
  max-width: 720px;
  color: var(--color-text-soft);
  font-size: 0.95rem;
}

.help-text {
  font-size: 0.85rem;
  color: var(--color-text-soft);
}

.error-message {
  margin-top: 0.4rem;
  color: #b91c1c;
  font-size: 0.9rem;
}

/* Buttons */

.btn-primary,
.btn-secondary,
.btn-outline {
  font-family: inherit;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
  padding: 0.6rem 1rem;
  transition: 0.15s ease-in-out;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.3rem;
}

.btn-primary {
  background: var(--color-primary);
  color: #ffffff;
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
}

.btn-secondary {
  background: #6c757d;
  color: #ffffff;
}

.btn-secondary:hover {
  background: #545b62;
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text);
}

.btn-outline:hover:not(:disabled) {
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
  transform: translateY(-1px);
}

button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
}

/* Generator layout */

.generator-layout {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 1.25rem;
  align-items: flex-start;
}

.generator-left,
.generator-right {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.form-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.form-group {
  flex: 1 1 180px;
  display: flex;
  flex-direction: column;
}

.form-group label {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.form-group input,
.form-group select {
  padding: 0.5rem 0.6rem;
  border-radius: 6px;
  border: 1px solid var(--color-border);
  font-size: 0.95rem;
}

.checkbox-group {
  justify-content: flex-end;
}

.checkbox-group label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 500;
  margin-bottom: 0;
}

.buttons-row {
  margin-top: 0.4rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

/* Preview & download */

.preview-card,
.download-card {
  background: var(--color-surface-alt);
  border-radius: 10px;
  border: 1px solid var(--color-border);
  padding: 1rem;
}

.preview-card h3,
.download-card h3 {
  margin: 0 0 0.6rem;
  font-size: 1rem;
}

.preview-inner {
  border-radius: 8px;
  border: 1px dashed var(--color-border);
  padding: 0.75rem;
  min-height: 140px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #ffffff;
}

#barcodeSvg {
  max-width: 100%;
}

.download-row {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

/* Benefits */

.benefits-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}

.benefit {
  background: var(--color-surface-alt);
  border-radius: 10px;
  border: 1px solid var(--color-border);
  padding: 1rem;
}

.benefit-icon {
  font-size: 1.5rem;
  margin-bottom: 0.4rem;
}

/* Steps */

.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}

.step {
  background: var(--color-surface-alt);
  border-radius: 10px;
  border: 1px solid var(--color-border);
  padding: 1rem;
}

.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.5rem;
  font-weight: 700;
}

/* Note box */

.note-box {
  text-align: center;
  padding: 0.9rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--color-primary);
  background: #e9f5ff;
  color: var(--color-primary-dark);
  font-size: 0.9rem;
}

/* FAQ */

.faq-item {
  margin-bottom: 0.75rem;
}

.faq-question {
  width: 100%;
  text-align: left;
  padding: 0.8rem 0.9rem;
  border-radius: 8px;
  border: 1px solid var(--color-border);
  background: var(--color-surface-alt);
  font-weight: 600;
  cursor: pointer;
  font-size: 0.95rem;
  color: var(--color-primary-dark);
}

.faq-answer {
  display: none;
  padding: 0.75rem 0.9rem;
  border-left: 3px solid var(--color-primary);
  background: var(--color-surface);
  border-radius: 0 0 8px 8px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  font-size: 0.92rem;
}

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

/* Footer */

.site-footer {
  background: #f1f1f1;
  color: var(--color-text-soft);
  text-align: center;
  padding: 1.5rem 1rem 2rem;
  font-size: 0.9rem;
}

.site-footer a {
  color: var(--color-primary);
  text-decoration: none;
}

.site-footer a:hover {
  text-decoration: underline;
}

/* Responsive */

@media (max-width: 900px) {
  .generator-layout {
    grid-template-columns: 1fr;
  }

  .header-inner {
    flex-direction: column;
  }
}

@media (max-width: 600px) {
  .card {
    padding: 1.25rem 1rem;
  }

  .site-header h1 {
    font-size: 1.6rem;
  }

  .buttons-row {
    flex-direction: column;
  }

  .btn-primary,
  .btn-secondary {
    width: 100%;
  }
}