:root {
  color-scheme: light dark;

  --bg: #f6f7f9;
  --surface: #ffffff;
  --border: #dfe3e8;
  --text: #1a1d21;
  --text-muted: #5c6570;
  --accent: #2f6fed;
  --accent-text: #ffffff;
  --danger: #b4232a;
  --success: #1a7f4b;
  --radius: 10px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --surface: #1c1f24;
    --border: #2c3138;
    --text: #e8eaed;
    --text-muted: #9aa4b0;
    --accent: #5b8dff;
    --accent-text: #0d1014;
    --danger: #ff8a8a;
    --success: #6ee7a8;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 2.5rem 1.25rem;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
}

.shell {
  margin: 0 auto;
  max-width: 46rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.shell__header h1 {
  margin: 0 0 0.35rem;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
}

.shell__subtitle {
  margin: 0;
  color: var(--text-muted);
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.panel__heading {
  margin: 0;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.panel__actions {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  flex-wrap: wrap;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.field__label {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.field__input {
  width: 100%;
  padding: 0.75rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  color: inherit;
  font: 0.95rem/1.6 ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
  resize: vertical;
}

.field__input:focus-visible,
.button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.button {
  padding: 0.6rem 1.3rem;
  border: none;
  border-radius: var(--radius);
  background: var(--accent);
  color: var(--accent-text);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
}

.button:hover:not(:disabled) {
  filter: brightness(1.08);
}

.button:disabled {
  opacity: 0.55;
  cursor: progress;
}

.status {
  margin: 0;
  min-height: 1.2em;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.status[data-tone="error"] {
  color: var(--danger);
  font-weight: 500;
}

.status[data-tone="success"] {
  color: var(--success);
  font-weight: 500;
}

.panel__hint {
  margin: -0.35rem 0 0;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.field-grid {
  display: grid;
  gap: 0.9rem;
  grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
}

.field__input--single {
  font: 0.95rem/1.4 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  resize: none;
}

.field__optional {
  font-weight: 400;
  letter-spacing: 0;
  text-transform: none;
  opacity: 0.75;
}

.field__error {
  font-size: 0.82rem;
  color: var(--danger);
}

.field__input[aria-invalid="true"] {
  border-color: var(--danger);
}

.button--secondary {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}

.button--secondary:hover:not(:disabled) {
  background: color-mix(in srgb, var(--accent) 10%, transparent);
  filter: none;
}

.output {
  margin: 0;
  padding: 0.9rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  font: 0.95rem/1.6 ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}