/*
 * feedback.css
 * The states a screen is in when it is not showing data: loading, working,
 * and empty. The system had none of these, which is a conspicuous gap for
 * internal tooling — most admin screens spend real time in all three.
 *
 *   .spinner   indeterminate "working"
 *   .progress  determinate, on native <progress>
 *   .skeleton  content-shaped placeholder
 *   .empty     the nothing-here state, with a way out
 *
 * Every one of these needs markup to be accessible; the classes only draw.
 * The required ARIA is documented per component below.
 */

/*
 * ── Spinner ─────────────────────────────────────────────────────────
 * Sized in em, so it scales with whatever font-size it sits in — put it in
 * a .btn and it matches the label; set font-size: 2rem for a page spinner.
 * Drawn with currentColor, so it inherits tone from its context.
 *
 *   <span class="spinner" aria-hidden="true"></span>
 *   <span class="visually-hidden" role="status">Loading invoices</span>
 *
 * The spinner itself is decorative — the live region is what announces.
 */
.spinner {
  display:       inline-block;
  inline-size:   1em;
  block-size:    1em;
  border:        2px solid color-mix(in srgb, currentColor 25%, transparent);
  border-block-start-color: currentColor;
  border-radius: 50%;
  animation:     fjs-spin var(--motion-spin) linear infinite;
  /* Keep it on the text baseline rather than hanging below it. */
  vertical-align: -0.125em;
}

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

/*
 * ── Progress ────────────────────────────────────────────────────────
 * Built on native <progress> (Principle 4), so role="progressbar", the
 * value, and the max are announced without any ARIA of our own. Omit the
 * value attribute and the browser renders its own indeterminate state.
 *
 *   <progress class="progress" value="70" max="100">70%</progress>
 *   <progress class="progress success" value="100" max="100">Done</progress>
 *
 * Reads --bg-mix, so any tone class colors the fill.
 */
.progress {
  appearance:    none;
  inline-size:   100%;
  block-size:    0.5rem;
  border:        none;
  border-radius: 999px;
  overflow:      hidden;
  /* Firefox paints the track here; WebKit needs the pseudo below. */
  background:    var(--surface-sunken);
  color:         var(--bg-mix, var(--color-primary));
}
.progress::-webkit-progress-bar {
  background:    var(--surface-sunken);
  border-radius: 999px;
}
.progress::-webkit-progress-value {
  background:    var(--bg-mix, var(--color-primary));
  border-radius: 999px;
  transition:    inline-size var(--motion-slow) var(--motion-ease);
}
.progress::-moz-progress-bar {
  background:    var(--bg-mix, var(--color-primary));
  border-radius: 999px;
}

/*
 * ── Skeleton ────────────────────────────────────────────────────────
 * A placeholder shaped like the content that is coming. Put it on the real
 * element and it inherits that element's box, so the layout does not jump
 * when the data lands.
 *
 *   <div class="skeleton" style="block-size: 1rem; inline-size: 60%"></div>
 *   <div class="skeleton text"></div>      <!-- one line of body text -->
 *   <div class="skeleton circle"></div>    <!-- avatar-shaped -->
 *
 * Wrap the region in aria-busy="true" so assistive tech is not told to read
 * a screenful of empty boxes.
 */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--surface-sunken) 25%,
    color-mix(in srgb, var(--ink) 8%, var(--surface-sunken)) 37%,
    var(--surface-sunken) 63%
  );
  background-size: 400% 100%;
  animation:       fjs-shimmer var(--motion-shimmer) var(--motion-ease) infinite;
  border-radius:   var(--btn-radius);
  /* Any text inside is a sizing hint, not content to read. */
  color:           transparent;
  user-select:     none;
}
.skeleton.text {
  block-size:       0.75em;
  border-radius:    999px;
  margin-block:     0.3em;
}
.skeleton.circle {
  border-radius: 50%;
  aspect-ratio:  1;
}

@keyframes fjs-shimmer {
  from { background-position: 100% 50%; }
  to   { background-position: 0 50%; }
}

/*
 * ── Empty state ─────────────────────────────────────────────────────
 * The nothing-here screen. An empty state without an action is a dead end,
 * so .empty-actions is part of the anatomy rather than an afterthought.
 *
 *   <div class="empty">
 *     <div class="empty-icon" aria-hidden="true">…</div>
 *     <h3 class="empty-title">No invoices yet</h3>
 *     <p class="empty-text">Create your first one to get started.</p>
 *     <div class="empty-actions">
 *       <button class="btn primary">New invoice</button>
 *     </div>
 *   </div>
 */
.empty {
  display:        grid;
  justify-items:  center;
  align-content:  center;
  text-align:     center;
  gap:            var(--space-sm);
  padding:        var(--space-6xl) var(--space-4xl);
  color:          var(--ink-soft);
}
.empty-icon {
  font-size:   var(--icon-size);
  line-height: 1;
  color:       var(--ink-mute);
}
/* Icon sizing: icon.css. .empty-icon sets --icon-size: 2rem there — and
   gets the `[class*=" i-heroicons"]` branch this rule was missing. The
   font-size above reads the same token so a text glyph matches an <svg>. */
.empty-title {
  margin:      0;
  font-size:   var(--text-xl);
  font-weight: 600;
  color:       var(--ink);
}
.empty-text {
  margin:      0;
  /* Hold the copy to a readable measure however wide the container is. */
  max-inline-size: 42ch;
  line-height: 1.55;
  /* At 42ch a widow is a whole line of nothing, right under the title. */
  text-wrap:   pretty;
}
.empty-actions {
  display:     flex;
  flex-wrap:   wrap;
  gap:         var(--space-sm);
  margin-block-start: 0.5rem;
}