:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b6b6b;
  --border: #d8d8d8;
  --card-bg: #f7f7f8;
  --accent: #2563eb;
  --accent-fg: #ffffff;
  --danger: #dc2626;
  --danger-fg: #ffffff;
  --error-bg: #fef2f2;
  --error-border: #fecaca;
  --error-fg: #991b1b;
  --code-bg: #0f172a;
  --code-fg: #e2e8f0;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --fg: #e8e8e8;
    --muted: #9a9a9a;
    --border: #2d2f36;
    --card-bg: #171a21;
    --accent: #3b82f6;
    --accent-fg: #0b0f19;
    --danger: #f87171;
    --danger-fg: #1a0505;
    --error-bg: #2a1414;
    --error-border: #5b1f1f;
    --error-fg: #fca5a5;
    --code-bg: #06080d;
    --code-fg: #d7e0ee;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.5;
}

.page-header,
.page-footer,
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem;
}

.page-header h1 {
  margin-bottom: 0.5rem;
}

.page-header p,
.page-footer p {
  color: var(--muted);
  font-size: 0.95rem;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}

.card h2 {
  margin-top: 0;
  font-size: 1.05rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  font-size: 0.9rem;
}

.field span {
  color: var(--muted);
}

input[type="text"],
input[type="number"],
select,
textarea {
  font: inherit;
  width: 100%;
  padding: 0.5rem 0.6rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--fg);
}

textarea {
  min-height: 4.5rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.85rem;
  resize: vertical;
}

.btn {
  font: inherit;
  padding: 0.55rem 1rem;
  border-radius: 6px;
  border: 1px solid transparent;
  cursor: pointer;
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-fg);
}

.btn-secondary {
  background: transparent;
  border-color: var(--border);
  color: var(--fg);
}

.btn-danger {
  background: transparent;
  border-color: var(--danger);
  color: var(--danger);
}

.restrictions-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.restriction-row {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.75rem;
  background: var(--bg);
}

.restriction-row-main {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 0.6rem;
  align-items: end;
}

.restriction-row-value {
  margin-top: 0.6rem;
}

.restriction-row-value:empty {
  margin-top: 0;
}

.checkbox-field {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
}

.row-error {
  color: var(--error-fg);
  font-size: 0.8rem;
  margin: 0.5rem 0 0;
}

.errors {
  background: var(--error-bg);
  border: 1px solid var(--error-border);
  color: var(--error-fg);
  border-radius: 8px;
  padding: 0.75rem 1rem;
  margin-top: 1rem;
  font-size: 0.9rem;
}

.errors ul {
  margin: 0.25rem 0 0;
  padding-left: 1.1rem;
}

.output {
  margin-top: 1.25rem;
}

.qr-container {
  display: flex;
  justify-content: center;
  background: #ffffff;
  padding: 1rem;
  border-radius: 8px;
}

.qr-container svg {
  width: 100%;
  max-width: 280px;
  height: auto;
}

.byte-count {
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

.output-actions {
  display: flex;
  gap: 0.6rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 0.75rem 0;
}

.json-preview pre {
  background: var(--code-bg);
  color: var(--code-fg);
  padding: 0.75rem;
  border-radius: 6px;
  overflow-x: auto;
  font-size: 0.8rem;
}