/* ═════════════════════════════════════════════════════════════════
   SuperCat DS — Field wrapper  ·  .kf-field
   ─────────────────────────────────────────────────────────────────
   ▸ Class prefix: `.kf-*` = "kit form".
   ▸ Pairs label + control + hint + validation message in one wrapper.
   ▸ Optional but recommended — gives consistent vertical rhythm and
     a single hook for [data-state="error|warn|success"].
   ▸ Pieces: .kf-field-label, .kf-field-hint, .kf-field-message,
              .kf-field-required, .kf-field-optional, .kf-field-counter
   ▸ Framework-agnostic. Pure CSS.
   ─────────────────────────────────────────────────────────────────
   .kf-field — Form field wrapper
   ─────────────────────────────────────────────────────────────────
   Framework-agnostic. Pure CSS. Pairs with .kf-input / .kf-check /
   .kf-switch / and any custom control. Provides:
     - Label
     - Required indicator
     - Hint
     - Validation message (error / warn / success)
     - Optional flag
     - Counter (e.g. character count)
     - Inline label layout (label-on-left)

   Usage (canonical pattern, framework-neutral):

     <div class="kf-field">
       <label class="kf-field-label" for="po">
         PO number
         <span class="kf-field-optional">Optional</span>
       </label>
       <input class="kf-input kf-md" id="po" type="text" />
       <p class="kf-field-hint">Auto-generated if blank.</p>
     </div>

   Required:
     <label class="kf-field-label" for="x">
       Buyer email <span class="kf-field-required" aria-hidden="true">*</span>
     </label>

   Validation:
     <div class="kf-field" data-state="error">
       <label class="kf-field-label">…</label>
       <input class="kf-input kf-md" data-state="error" />
       <p class="kf-field-message">Maximum order qty is 250.</p>
     </div>

   Counter (right-aligned, paired with hint or message):
     <div class="kf-field-meta">
       <p class="kf-field-hint">Visible to dealer + warehouse.</p>
       <span class="kf-field-counter">142 / 500</span>
     </div>

   Inline (label-on-left):
     <div class="kf-field kf-field-inline">…</div>

   API
   ───
   States       : data-state="error|warn|success" — tints message + label
   Layout       : kf-field-inline   horizontal label + control
                  kf-field-tight    smaller gap (for dense forms)
   ─────────────────────────────────────────────────────────────── */

.kf-field,
:where(.kf-field) {
  display: flex;
  flex-direction: column;
  gap: 6px; /* tight: label sits close to its control */
  font-family: var(--font-sans);
}
.kf-field > .kf-field-hint,
.kf-field > .kf-field-message,
.kf-field > .kf-field-meta {
  margin-top: 2px; /* hint/message gets a touch more breathing room from input */
}

.kf-field.kf-field-tight { gap: var(--space-1); }

/* ── Label ─────────────────────────────────────────────────────── */
.kf-field-label {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-2xs);
  font-family: var(--font-mono);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: var(--weight-semibold);
  /* Click-through to the associated input is the browser default */
  cursor: pointer;
}

.kf-field-required {
  color: var(--text-crimson);
  font-family: var(--font-sans);
  font-weight: var(--weight-bold);
  /* Use letter-spacing reset because parent has wider tracking */
  letter-spacing: 0;
  font-size: 1.1em;
  line-height: 0;
  margin-left: -2px; /* tighten against label text */
}

.kf-field-optional {
  font-style: normal;
  color: var(--text-faint);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-wider);
  font-weight: var(--weight-medium);
  text-transform: uppercase;
}

/* ── Hint (helper text, neutral) ───────────────────────────────── */
.kf-field-hint {
  margin: 0;
  font-size: var(--text-xs);
  color: var(--text-muted);
  line-height: var(--leading-snug);
}

/* ── Message (validation feedback, tone follows data-state) ────── */
.kf-field-message {
  margin: 0;
  font-size: var(--text-xs);
  color: var(--text-muted);
  line-height: var(--leading-snug);
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
}

/* Tone — applied to message + parent field.
   Error uses --status-danger (orange-red) so it stays visually distinct
   from --text-crimson (brand primary). */
.kf-field[data-state="error"]   .kf-field-message,
.kf-field-message[data-state="error"]   { color: var(--status-danger); }
.kf-field[data-state="warn"]    .kf-field-message,
.kf-field-message[data-state="warn"]    { color: var(--color-gold); }
.kf-field[data-state="success"] .kf-field-message,
.kf-field-message[data-state="success"] { color: var(--status-success); }

/* When the field is in an error state, also tint the label so multi-error
   forms scan at a glance. Uses --status-danger (NOT crimson). */
.kf-field[data-state="error"] > .kf-field-label {
  color: var(--status-danger);
}

/* ── Error shake ───────────────────────────────────────────────────
   Add `.kf-shake` to any error-state element to play a one-shot
   horizontal shake. Designed to be added on submit / on first error
   reveal — the class auto-removes via animation event in JS, OR you
   can toggle the class yourself. The animation plays once and stops.
   Subtle by design (4px, 320ms) — alarm-volume shakes feel angry. */
@keyframes kf-shake {
  0%, 100% { transform: translateX(0); }
  20%      { transform: translateX(-4px); }
  40%      { transform: translateX(4px); }
  60%      { transform: translateX(-3px); }
  80%      { transform: translateX(2px); }
}
.kf-shake {
  animation: kf-shake 320ms var(--ease-out) both;
}
@media (prefers-reduced-motion: reduce) {
  .kf-shake { animation: none; }
}

/* ── Meta row (hint + counter, etc.) ───────────────────────────── */
.kf-field-meta {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-3);
}

.kf-field-counter {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--text-2xs);
  letter-spacing: var(--tracking-wider);
  color: var(--text-faint);
  font-feature-settings: "tnum";
}

.kf-field-counter[data-state="warn"]  { color: var(--color-gold); }
.kf-field-counter[data-state="error"] { color: var(--status-danger); }

/* ── Inline layout (label on the left) ─────────────────────────── */
.kf-field.kf-field-inline {
  flex-direction: row;
  align-items: center;
  gap: var(--space-5);
}
.kf-field.kf-field-inline > .kf-field-label {
  flex: 0 0 auto;
  min-width: 120px;
  margin-bottom: 0;
}
.kf-field.kf-field-inline > .kf-input,
.kf-field.kf-field-inline > .kf-input-wrap {
  flex: 1 1 auto;
}

/* ── Fieldset wrapper (for radio/checkbox groups) ──────────────── */
/* Lets consumers use semantic <fieldset>/<legend> with our typography */
.kf-fieldset {
  border: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.kf-fieldset > legend {
  /* Same look as kf-field-label */
  font-size: var(--text-2xs);
  font-family: var(--font-mono);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: var(--weight-semibold);
  padding: 0;
  margin-bottom: var(--space-2);
}