:root {
  --bg: #fafafa;
  --card-bg: #ffffff;
  --border: #e2e2e2;
  --text: #1a1a1a;
  --text-muted: #6b6b6b;
  --accent: #2563eb;
  --accent-grad-start: #1d4ed8;
  --accent-grad-mid: #2563eb;
  --accent-grad-end: #06b6d4;
  --radius: 14px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 0 16px 60px;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Pretendard", "Apple SD Gothic Neo", Roboto, sans-serif;
  line-height: 1.55;
}

.lang-switch {
  max-width: 640px;
  margin: 20px auto 0;
  display: flex;
  justify-content: flex-end;
  gap: 6px;
}

.lang-btn {
  border: 1px solid var(--border);
  background: var(--card-bg);
  color: var(--text-muted);
  border-radius: 999px;
  padding: 5px 14px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s, background 0.15s;
}

.lang-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background: #eff6ff;
  font-weight: 600;
}

.page-header {
  max-width: 640px;
  margin: 0 auto;
  padding: 20px 0 20px;
  text-align: center;
}

.page-header h1 {
  font-size: 1.6rem;
  margin: 0 0 8px;
  background: linear-gradient(90deg, var(--accent-grad-start), var(--accent-grad-mid), var(--accent-grad-end));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0;
}

main {
  max-width: 640px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
}

.card h2 {
  font-size: 1.05rem;
  margin: 0 0 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-grad-start), var(--accent-grad-mid));
  color: white;
  font-size: 0.85rem;
  flex-shrink: 0;
}

.row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.text-input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 1rem;
  font-family: inherit;
}

.text-input:focus {
  outline: none;
  border-color: var(--accent);
}

input[type="number"] {
  width: 100px;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
}

.hint {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin: 8px 0 0;
}

.direct-note {
  color: #1d4ed8;
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  border-radius: 8px;
  padding: 8px 12px;
  margin-top: 12px;
}

.error-hint {
  color: #b91c1c;
}

.error-hint:empty { display: none; }

.preset-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 10px;
}

.preset-option {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 14px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  transition: border-color 0.15s, background 0.15s;
}

.preset-option:has(input:checked) {
  border-color: var(--accent);
  background: #eff6ff;
}

.preset-option small {
  color: var(--text-muted);
}

.color-field {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.color-field input[type="color"] {
  width: 40px;
  height: 32px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  background: none;
}

#eccGroup {
  margin-top: 4px;
}

.ecc-btn {
  border: 1px solid var(--border);
  background: var(--card-bg);
  color: var(--text-muted);
  width: 40px;
  height: 36px;
  border-radius: 8px;
  font-weight: 700;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, color 0.15s;
}

.ecc-btn.active {
  border-color: var(--accent);
  background: #eff6ff;
  color: var(--accent);
}

.qr-preview-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 220px;
  background: #f6f6f7;
  border-radius: 12px;
  padding: 20px;
}

#qrCanvas {
  max-width: 260px;
  width: 100%;
  height: auto;
  display: none;
  border-radius: 8px;
}

#qrCanvas.visible {
  display: block;
}

#emptyHint {
  margin: 0;
  text-align: center;
}

#emptyHint.hidden {
  display: none;
}

.dl-row {
  display: flex;
  gap: 10px;
  margin-top: 16px;
}

.download-btn {
  flex: 1;
  padding: 14px;
  border: none;
  border-radius: 10px;
  background: linear-gradient(90deg, var(--accent-grad-start), var(--accent-grad-mid), var(--accent-grad-end));
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
}

.download-btn.secondary {
  background: var(--card-bg);
  border: 1px solid var(--border);
  color: var(--text);
}

.download-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.page-footer {
  max-width: 640px;
  margin: 30px auto 0;
  color: var(--text-muted);
  font-size: 0.78rem;
  text-align: center;
  line-height: 1.3;
}

.legal-group {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-footer .legal {
  margin: 0;
}

.meta-group {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-footer .contact {
  margin: 0;
  font-size: 0.78rem;
}

.page-footer .contact a {
  color: var(--accent);
  text-decoration: none;
}

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

.page-footer .copyright {
  margin: 0;
  font-size: 0.75rem;
  color: #a0a0a0;
}