/* ============================================================================
   f(x) → NATURE DS — Feedback & Status [04]
   Documented styled in sections/feedback.html. Component primitives only:
   Alert, Toast, Tooltip, Hover Card, Progress, Spinner + dots, Skeleton,
   Gauge, Empty. Toast + hovercard interaction lives in scripts/main.js.
   Consumes ONLY tokens.css custom properties — no hard-coded color, no resets.
   Doc chrome (.fd-doc, .fd-preview, .fd-api, .fd-doc__*) lives in styles/docs.css
   and is NEVER redefined here. Correct in both dark (default) and light themes.
   ============================================================================ */

/* ============================================================================
   ALERT  (renamed from Note/Callout — default/info/success/warning/error)
   ============================================================================ */
.fd-alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  width: 100%;
  max-width: 520px;
  padding: var(--space-4);
  background: var(--surface-2);
  border: var(--border-width) solid var(--border);
  border-left: var(--border-width-thick) solid var(--foreground-subtle);
  border-radius: var(--radius-sm);
}
.fd-alert__icon {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 20px;
  height: 20px;
  margin-top: 1px;
  color: var(--foreground-subtle);
}
.fd-alert__icon svg { width: 18px; height: 18px; }
.fd-alert__body { min-width: 0; }
.fd-alert__title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--foreground);
  margin-bottom: var(--space-1);
}
.fd-alert__text {
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--foreground-muted);
}
.fd-alert__text code {
  font-size: 0.92em;
  padding: 0 var(--space-1);
  background: var(--surface-3);
  border-radius: var(--radius-sm);
  color: var(--foreground);
}
.fd-alert__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.fd-alert--info {
  background: var(--info-muted);
  border-left-color: var(--info);
}
.fd-alert--info .fd-alert__icon { color: var(--info-text); }
.fd-alert--success {
  background: var(--success-muted);
  border-left-color: var(--success);
}
.fd-alert--success .fd-alert__icon { color: var(--success-text); }
.fd-alert--warning {
  background: var(--warning-muted);
  border-left-color: var(--warning);
}
.fd-alert--warning .fd-alert__icon { color: var(--warning-text); }
.fd-alert--error {
  background: var(--error-muted);
  border-left-color: var(--error);
}
.fd-alert--error .fd-alert__icon { color: var(--error-text); }

/* --- Note / Callout aliases — the unchanged feedback section markup uses the
   original .fd-note* names; map them onto the Alert primitive above. -------- */
.fd-note {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  width: 100%;
  max-width: 520px;
  padding: var(--space-4);
  background: var(--surface-2);
  border: var(--border-width) solid var(--border);
  border-left: var(--border-width-thick) solid var(--foreground-subtle);
  border-radius: var(--radius-sm);
}
.fd-note__icon {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 20px;
  height: 20px;
  margin-top: 1px;
  color: var(--foreground-subtle);
}
.fd-note__icon svg { width: 18px; height: 18px; }
.fd-note__body { min-width: 0; }
.fd-note__title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--foreground);
  margin-bottom: var(--space-1);
}
.fd-note__text {
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--foreground-muted);
}
.fd-note__text code {
  font-size: 0.92em;
  padding: 0 var(--space-1);
  background: var(--surface-3);
  border-radius: var(--radius-sm);
  color: var(--foreground);
}
.fd-note--info { background: var(--info-muted); border-left-color: var(--info); }
.fd-note--info .fd-note__icon { color: var(--info-text); }
.fd-note--success { background: var(--success-muted); border-left-color: var(--success); }
.fd-note--success .fd-note__icon { color: var(--success-text); }
.fd-note--warning { background: var(--warning-muted); border-left-color: var(--warning); }
.fd-note--warning .fd-note__icon { color: var(--warning-text); }
.fd-note--error { background: var(--error-muted); border-left-color: var(--error); }
.fd-note--error .fd-note__icon { color: var(--error-text); }

/* ============================================================================
   TOAST  (Sonner-style; region + JS owned by assembler. We style the elements
   main.js makes, plus a static preview variant so the anatomy reads inline.)
   ============================================================================ */
.fd-toast {
  position: relative;
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  width: 100%;
  max-width: 360px;
  padding: var(--space-3) var(--space-4);
  background: var(--surface);
  color: var(--foreground);
  border: var(--border-width) solid var(--border-strong);
  border-left: var(--border-width-thick) solid var(--foreground-subtle);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  /* enter/exit */
  opacity: 0;
  transform: translateX(8px) scale(0.98);
  transition: opacity var(--duration-base) var(--ease-out),
    transform var(--duration-base) var(--ease-out);
}
.fd-toast.is-open {
  opacity: 1;
  transform: translateX(0) scale(1);
}
.fd-toast__icon {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 18px;
  height: 18px;
  margin-top: 1px;
  color: var(--foreground-subtle);
}
.fd-toast__icon svg { width: 16px; height: 16px; }
.fd-toast__body { flex: 1 1 auto; min-width: 0; }
.fd-toast__title {
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--foreground);
}
.fd-toast__msg {
  margin-top: 2px;
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
  color: var(--foreground-muted);
}
.fd-toast__close {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  margin: -2px -2px 0 0;
  color: var(--foreground-subtle);
  border: var(--border-width) solid transparent;
  border-radius: var(--radius-sm);
  background: none;
  cursor: pointer;
  transition: color var(--duration-fast) var(--ease-out),
    border-color var(--duration-fast) var(--ease-out);
}
.fd-toast__close:hover {
  color: var(--foreground);
  border-color: var(--border);
}
.fd-toast__close svg { width: 13px; height: 13px; }

.fd-toast--success { border-left-color: var(--success); }
.fd-toast--success .fd-toast__icon { color: var(--success-text); }
.fd-toast--error { border-left-color: var(--error); }
.fd-toast--error .fd-toast__icon { color: var(--error-text); }
.fd-toast--warning { border-left-color: var(--warning); }
.fd-toast--warning .fd-toast__icon { color: var(--warning-text); }
.fd-toast--info { border-left-color: var(--info); }
.fd-toast--info .fd-toast__icon { color: var(--info-text); }
.fd-toast--default { border-left-color: var(--accent); }
.fd-toast--default .fd-toast__icon { color: var(--accent-text); }

/* Static preview wrapper so the anatomy is visible without firing JS. */
.fd-toast--static {
  opacity: 1;
  transform: none;
  transition: none;
}

/* ============================================================================
   TOOLTIP  (pure CSS, hover / focus-within)
   ============================================================================ */
.fd-tooltip {
  position: relative;
  display: inline-flex;
}
.fd-tooltip__content {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  z-index: var(--z-tooltip);
  width: max-content;
  max-width: 220px;
  padding: var(--space-2) var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-wide);
  line-height: var(--leading-snug);
  color: var(--background);
  background: var(--foreground);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration-fast) var(--ease-out),
    transform var(--duration-fast) var(--ease-out);
}
.fd-tooltip__content::after {
  content: "";
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-top-color: var(--foreground);
}
.fd-tooltip:hover .fd-tooltip__content,
.fd-tooltip:focus-within .fd-tooltip__content {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* placement modifiers */
.fd-tooltip__content--bottom {
  bottom: auto;
  top: calc(100% + 8px);
  transform: translateX(-50%) translateY(-4px);
}
.fd-tooltip__content--bottom::after {
  top: auto;
  bottom: 100%;
  border-top-color: transparent;
  border-bottom-color: var(--foreground);
}
.fd-tooltip:hover .fd-tooltip__content--bottom,
.fd-tooltip:focus-within .fd-tooltip__content--bottom {
  transform: translateX(-50%) translateY(0);
}
.fd-tooltip__content--right {
  bottom: auto;
  top: 50%;
  left: calc(100% + 8px);
  transform: translateY(-50%) translateX(-4px);
}
.fd-tooltip__content--right::after {
  top: 50%;
  left: auto;
  right: 100%;
  transform: translateY(-50%);
  border-top-color: transparent;
  border-right-color: var(--foreground);
}
.fd-tooltip:hover .fd-tooltip__content--right,
.fd-tooltip:focus-within .fd-tooltip__content--right {
  transform: translateY(-50%) translateX(0);
}
.fd-tooltip__content--left {
  bottom: auto;
  top: 50%;
  left: auto;
  right: calc(100% + 8px);
  transform: translateY(-50%) translateX(4px);
}
.fd-tooltip__content--left::after {
  top: 50%;
  left: 100%;
  right: auto;
  transform: translateY(-50%);
  border-top-color: transparent;
  border-left-color: var(--foreground);
}
.fd-tooltip:hover .fd-tooltip__content--left,
.fd-tooltip:focus-within .fd-tooltip__content--left {
  transform: translateY(-50%) translateX(0);
}

/* small dotted info trigger used in examples */
.fd-tooltip__trigger {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--foreground-muted);
  border-bottom: var(--border-width) dashed var(--border-strong);
  cursor: help;
}
.fd-tooltip__trigger:hover { color: var(--foreground); }

/* ============================================================================
   HOVER CARD  (pure CSS, hover / focus-within — richer than a tooltip)
   ============================================================================ */
.fd-hovercard {
  position: relative;
  display: inline-flex;
}
.fd-hovercard__trigger {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: var(--tracking-wide);
  color: var(--accent-text);
  background: none;
  border: 0;
  border-bottom: var(--border-width) dashed var(--accent-border);
  padding: 0 0 1px;
  cursor: pointer;
}
.fd-hovercard__trigger:hover { color: var(--accent-hover); }
.fd-hovercard__trigger:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}
.fd-hovercard__content {
  position: absolute;
  top: calc(100% + 10px);
  left: 0;
  z-index: var(--z-tooltip);
  width: max-content;
  max-width: 300px;
  padding: var(--space-4);
  background: var(--surface);
  border: var(--border-width) solid var(--border-strong);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(4px);
  pointer-events: none;
  transition: opacity var(--duration-base) var(--ease-out),
    transform var(--duration-base) var(--ease-out);
}
/* a thin lime tick on the top-left corner — crosshair nod */
.fd-hovercard__content::before {
  content: "";
  position: absolute;
  top: -1px;
  left: var(--space-4);
  width: var(--space-6);
  height: var(--border-width-thick);
  background: var(--accent);
}
.fd-hovercard:hover .fd-hovercard__content,
.fd-hovercard:focus-within .fd-hovercard__content {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}
.fd-hovercard__content--right { left: auto; right: 0; }
.fd-hovercard__content--right::before { left: auto; right: var(--space-4); }

.fd-hovercard__head {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}
.fd-hovercard__avatar {
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-wide);
  color: var(--on-accent);
  background: var(--accent);
  border-radius: var(--radius-sm);
}
.fd-hovercard__name {
  font-family: var(--font-display);
  font-size: var(--text-base);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  color: var(--foreground);
}
.fd-hovercard__handle {
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-wide);
  color: var(--foreground-subtle);
}
.fd-hovercard__text {
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--foreground-muted);
}
.fd-hovercard__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-top: var(--space-3);
  padding-top: var(--space-3);
  border-top: var(--border-width) solid var(--border);
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--foreground-subtle);
}
.fd-hovercard__meta b {
  color: var(--foreground);
  font-weight: var(--weight-semibold);
}

/* ============================================================================
   PROGRESS  (determinate + indeterminate)
   ============================================================================ */
.fd-progress {
  width: 100%;
  min-width: 180px;
}
.fd-progress__track {
  position: relative;
  width: 100%;
  height: 8px;
  background: var(--surface-3);
  border: var(--border-width) solid var(--border);
  border-radius: var(--radius-full);
  overflow: hidden;
}
.fd-progress__bar {
  height: 100%;
  background: var(--accent);
  border-radius: var(--radius-full);
  transition: width var(--duration-slow) var(--ease-out);
}
.fd-progress__meta {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--foreground-subtle);
}
.fd-progress__value { color: var(--foreground); }

/* semantic fills */
.fd-progress--success .fd-progress__bar { background: var(--success); }
.fd-progress--warning .fd-progress__bar { background: var(--warning); }
.fd-progress--error .fd-progress__bar { background: var(--error); }

/* indeterminate */
.fd-progress--indeterminate .fd-progress__bar {
  width: 38%;
  border-radius: var(--radius-full);
  animation: fd-progress-slide 1.3s var(--ease-in-out) infinite;
}
@keyframes fd-progress-slide {
  0% { transform: translateX(-110%); }
  100% { transform: translateX(330%); }
}

/* ============================================================================
   SPINNER + LOADING DOTS
   ============================================================================ */
.fd-spinner {
  display: inline-block;
  width: 28px;
  height: 28px;
  border: var(--border-width-thick) solid var(--border-strong);
  border-top-color: var(--accent);
  border-radius: var(--radius-full);
  animation: fd-spin 0.7s linear infinite;
}
.fd-spinner--sm { width: 16px; height: 16px; border-width: var(--border-width-thick); }
.fd-spinner--lg { width: 44px; height: 44px; border-width: 3px; }
.fd-spinner--muted { border-top-color: var(--foreground); }

@keyframes fd-spin {
  to { transform: rotate(360deg); }
}

.fd-dots {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}
.fd-dots span {
  width: 7px;
  height: 7px;
  border-radius: var(--radius-full);
  background: var(--accent);
  animation: fd-dot-pulse 1.1s ease-in-out infinite;
}
.fd-dots span:nth-child(2) { animation-delay: 0.18s; }
.fd-dots span:nth-child(3) { animation-delay: 0.36s; }
.fd-dots--muted span { background: var(--foreground-subtle); }

@keyframes fd-dot-pulse {
  0%, 80%, 100% { opacity: 0.25; transform: scale(0.7); }
  40% { opacity: 1; transform: scale(1); }
}

/* ============================================================================
   SKELETON
   ============================================================================ */
.fd-skeleton {
  position: relative;
  background: var(--surface-3);
  border-radius: var(--radius-sm);
  overflow: hidden;
}
.fd-skeleton::after {
  content: "";
  position: absolute;
  inset: 0;
  transform: translateX(-100%);
  background: linear-gradient(
    90deg,
    transparent 0%,
    var(--surface-2) 50%,
    transparent 100%
  );
  animation: fd-shimmer 1.4s ease-in-out infinite;
}
@keyframes fd-shimmer {
  100% { transform: translateX(100%); }
}

.fd-skeleton--line { height: 12px; width: 100%; }
.fd-skeleton--line.is-sm { height: 10px; }
.fd-skeleton--title { height: 18px; width: 60%; }
.fd-skeleton--avatar {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  flex: 0 0 auto;
}
.fd-skeleton--thumb { width: 100%; height: 96px; border-radius: var(--radius-sm); }
.fd-skeleton--btn { width: 96px; height: 32px; }

.fd-skeleton-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  width: 260px;
  padding: var(--space-4);
  background: var(--surface-2);
  border: var(--border-width) solid var(--border);
  border-radius: var(--radius-sm);
}
.fd-skeleton-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.fd-skeleton-lines {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  flex: 1 1 auto;
}

/* width helpers for skeleton lines */
.fd-skeleton.w-40 { width: 40%; }
.fd-skeleton.w-60 { width: 60%; }
.fd-skeleton.w-80 { width: 80%; }
.fd-skeleton.w-90 { width: 90%; }

/* ============================================================================
   GAUGE  (circular SVG meter)
   ============================================================================ */
.fd-gauge {
  position: relative;
  display: inline-grid;
  place-items: center;
  width: 112px;
  height: 112px;
}
.fd-gauge svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
  overflow: visible;
}
.fd-gauge__track {
  fill: none;
  stroke: var(--surface-3);
  stroke-width: 8;
}
.fd-gauge__fill {
  fill: none;
  stroke: var(--accent);
  stroke-width: 8;
  stroke-linecap: butt;
  transition: stroke-dasharray var(--duration-slow) var(--ease-out);
}
.fd-gauge__fill--success { stroke: var(--success); }
.fd-gauge__fill--warning { stroke: var(--warning); }
.fd-gauge__fill--error { stroke: var(--error); }
.fd-gauge__center {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  text-align: center;
}
.fd-gauge__num {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-tight);
  color: var(--foreground);
  line-height: var(--leading-none);
}
.fd-gauge__unit { font-size: var(--text-sm); color: var(--foreground-subtle); }
.fd-gauge__label {
  display: block;
  margin-top: 2px;
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--foreground-subtle);
}
/* compact size for tight rows */
.fd-gauge--sm { width: 84px; height: 84px; }
.fd-gauge--sm .fd-gauge__num { font-size: var(--text-base); }
.fd-gauge--sm .fd-gauge__label { display: none; }

/* ============================================================================
   EMPTY  (empty-state placeholder — icon, title, message, optional action)
   ============================================================================ */
.fd-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--space-3);
  width: 100%;
  max-width: 420px;
  padding: var(--space-12) var(--space-8);
  background: var(--surface);
  border: var(--border-width) dashed var(--border-strong);
  border-radius: var(--radius-sm);
}
.fd-empty__icon {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  margin-bottom: var(--space-1);
  color: var(--foreground-subtle);
  background: var(--surface-2);
  border: var(--border-width) solid var(--border);
  border-radius: var(--radius-sm);
}
.fd-empty__icon svg { width: 26px; height: 26px; }
.fd-empty__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  text-transform: uppercase;
  color: var(--foreground);
}
.fd-empty__text {
  max-width: 36ch;
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  color: var(--foreground-muted);
}
.fd-empty__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-2);
}
/* a compact inline variant for cards / panels */
.fd-empty--compact {
  padding: var(--space-8) var(--space-6);
}
.fd-empty--compact .fd-empty__icon {
  width: 40px;
  height: 40px;
}
.fd-empty--compact .fd-empty__icon svg { width: 20px; height: 20px; }

/* ============================================================================
   MOTION SAFETY  (base.css also caps durations globally)
   ============================================================================ */
@media (prefers-reduced-motion: reduce) {
  .fd-spinner,
  .fd-dots span,
  .fd-progress--indeterminate .fd-progress__bar,
  .fd-skeleton::after { animation: none; }
  .fd-hovercard__content,
  .fd-tooltip__content { transition: none; }
}