Hairline stat strip

<p class="hss-caption">Reporting only — the figures are the whole job.</p>
<div class="hss-strip four">
  <div class="hss-tile"><span class="hss-label">Documents</span><span class="hss-figure">1,482</span><span class="hss-sub">this period</span></div>
  <div class="hss-tile"><span class="hss-label">Median time</span><span class="hss-figure">3.2s</span><span class="hss-sub">last 24h</span></div>
  <div class="hss-tile"><span class="hss-label">Clean runs</span><span class="hss-figure">98.4%</span><span class="hss-sub">no retries</span></div>
  <div class="hss-tile"><span class="hss-label">Quality score</span><span class="hss-figure none" aria-label="No value">—</span><span class="hss-sub">not rated yet</span></div>
</div>
<p class="hss-caption">Same strip, working as the filter. Press a tile to narrow the list; press it again to clear.</p>
<div class="hss-strip five" data-hss-filter role="group" aria-label="Filter downloads by status">
  <button class="hss-tile" type="button" data-state="all" aria-pressed="false"><span class="hss-label">All</span><span class="hss-figure">6</span><span class="hss-sub">downloads</span></button>
  <button class="hss-tile" type="button" data-state="queued" aria-pressed="false"><span class="hss-label">Queued</span><span class="hss-figure">2</span><span class="hss-sub">downloads</span></button>
  <button class="hss-tile" type="button" data-state="downloading" aria-pressed="false"><span class="hss-label">Downloading</span><span class="hss-figure">1</span><span class="hss-sub">downloads</span></button>
  <button class="hss-tile" type="button" data-state="done" aria-pressed="false"><span class="hss-label">Done</span><span class="hss-figure">2</span><span class="hss-sub">downloads</span></button>
  <button class="hss-tile" type="button" data-state="failed" aria-pressed="false"><span class="hss-label">Failed</span><span class="hss-figure">1</span><span class="hss-sub">downloads</span></button>
</div>
<ul class="hss-list" data-hss-list>
  <li data-state="done"><span>Bicycle drivetrain teardown</span><span class="st">Done</span></li>
  <li data-state="downloading"><span>Kiln firing, part three</span><span class="st">Downloading</span></li>
  <li data-state="queued"><span>Field recording — marsh at dawn</span><span class="st">Queued</span></li>
  <li data-state="done"><span>Lathe restoration, episode 12</span><span class="st">Done</span></li>
  <li data-state="failed"><span>Sourdough hydration tests</span><span class="st">Failed</span></li>
  <li data-state="queued"><span>Bookbinding: the long stitch</span><span class="st">Queued</span></li>
</ul>
<p class="hss-status" data-hss-status role="status" aria-live="polite">Showing all 6 downloads.</p>

Colors come from shared theme tokens — --surface, --ink, --border, --accent and friends — so this CSS carries no palette of its own. Use Runnable file to copy the tokens along with it.

.hss-strip {
  display: grid;
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  grid-template-columns: 1fr;
}
@container (min-width: 21rem) { .hss-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@container (min-width: 42rem) { .hss-strip { grid-template-columns: repeat(4, minmax(0, 1fr)); } }

.hss-tile { background: var(--surface); padding: 0.85rem 1rem; display: grid; gap: 0.15rem; min-width: 0; }
.hss-label { font-family: ui-monospace, monospace; font-size: 0.8125rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--dim); }
.hss-figure { font-size: 1.6rem; font-weight: 700; font-variant-numeric: tabular-nums; }
.hss-figure.none { color: var(--dim); font-weight: 400; }
.hss-tile[aria-pressed="true"] { background: color-mix(in srgb, var(--accent) 14%, var(--surface)); }

:root {
  --ground: #eef0f3; --surface: #ffffff; --surface-2: #f5f7f9; --border: #d2d8e0;
  --ink: #161b22; --dim: #56606e; --accent: #364f6a; --radius: 10px;
}
@media (prefers-color-scheme: dark) {
  :root { --ground: #10141a; --surface: #191f27; --surface-2: #202834; --border: #2c3743; --ink: #e6ecf3; --dim: #97a4b4; --accent: #6f92bd; }
}
body { background: var(--ground); color: var(--ink); container-type: inline-size; }

const strip = document.querySelector('[data-hss-filter]');
const rows = [...document.querySelectorAll('[data-hss-list] li')];
strip.addEventListener('click', (event) => {
  const tile = event.target.closest('button');
  if (!tile) return;
  const wasPressed = tile.getAttribute('aria-pressed') === 'true';
  const target = wasPressed || tile.dataset.state === 'all' ? 'all' : tile.dataset.state;
  strip.querySelectorAll('button').forEach((other) => {
    other.setAttribute('aria-pressed', String(target !== 'all' && other.dataset.state === target));
  });
  rows.forEach((row) => { row.hidden = target !== 'all' && row.dataset.state !== target; });
});

Build a strip of statistic tiles that reads as one joined instrument panel rather than a row of floating cards.

The separators between tiles must not be borders. Make the container a CSS grid with `gap: 1px` and give the container itself the border color as its background; each tile then paints the surface color on top. The 1px of container showing through the gap is the hairline. This is the entire pattern: real borders double where two tiles meet and leave a stray edge when auto-fit wraps the row, and a gap physically cannot do either.

The full prompt continues with sections on pinning column counts, tile anatomy, two rules of honesty (render a missing value as a dimmed em dash; keep units with the number), the filter form, computing counts from the unfiltered set, and using aria-pressed rather than tab roles.