/*
 * grades.css — grade-catalog table on the homepage (#grades section).
 *
 * Visual brief: deliberately dense supplier-catalog look — 0px corners,
 * hairline rules, monospace accents, no drop shadows. Each <a> row is
 * a clickable deep-link to that grade's datasheet panel
 * (datasheets.html#grade-<slug>).
 *
 * Coupled with:
 *   - HTML markup in index.html under <section class="slab grades">
 *   - js/grade-data.js (5 grades; this CSS lays out 5 rows)
 *
 * Mobile layout (≤720px):
 *   The 4-column grid collapses to a 2-row layout per entry —
 *   (name | gf | ref) on top, full-width "查看 →" CTA below — so long
 *   import-equivalent strings can wrap without breaking column rhythm.
 *
 * Last refactor: 2026-04-28 — extracted from the original cases.css
 *   when grades / comparison / gallery were split into 3 files.
 */

.grades {
  padding-top: 96px;
  padding-bottom: 40px;
}

.grade-table {
  display: block;
  background: var(--bg-card);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
  border-right: 1px solid var(--line);
  /* tabular-nums so the GF % column lines up vertically across rows. */
  font-feature-settings: "tnum" 1, "calt" 0;
}

/* === Header row ======================================================= */
.grade-table-head {
  display: grid;
  grid-template-columns: 160px 120px 1fr 120px;
  gap: 0;
  padding: 14px 24px;
  background: var(--bg-soft);
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-faint);
}

.grade-table-head > div {
  padding: 0 12px;
}

/* === Data row (whole row is a link) =================================== */
.grade-row {
  display: grid;
  grid-template-columns: 160px 120px 1fr 120px;
  gap: 0;
  padding: 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  color: var(--text);
  transition: background .12s ease;
}

.grade-row:hover {
  background: var(--accent-soft);
}

.grade-row > div {
  padding: 16px 24px 16px 12px;
  display: flex;
  align-items: center;
}
.grade-row > div:first-child {
  padding-left: 36px;   /* mirrors 24px table padding + 12px head gutter */
}

/* Column 1 — grade name (M60SFB etc.) */
.grade-row-name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--text);
}

/* Column 2 — GF percentage */
.grade-row-gf {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--accent-dark);
}

/* Column 3 — currently tensile strength (was previously import equivalent;
   swappable per js/grade-data.js record). */
.grade-row-ref {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-dim);
  letter-spacing: 0.005em;
}

/* === Row CTA chip — visible "查看 →" pill so the row reads as clickable
   even when the whole row is already a link. Switches to navy on hover. */
.grade-row-cta {
  justify-content: flex-end;
  padding-right: 18px;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text);
}

.grade-row-cta > span:first-child {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  color: var(--text);
  white-space: nowrap;
  transition: background .12s ease, color .12s ease, border-color .12s ease;
}

.grade-row-cta-arrow {
  font-family: var(--font-body);
  font-weight: 400;
  letter-spacing: 0;
  transition: transform .12s ease;
}

.grade-row:hover .grade-row-cta > span:first-child {
  background: var(--accent-dark);
  color: var(--accent-on);
  border-color: var(--accent-dark);
}

.grade-row:hover .grade-row-cta-arrow {
  color: var(--accent-on);
  transform: translateX(3px);
}

/* === Mobile (≤720px) =================================================
   Reflow each row into a 2-line layout so a long ref string can wrap
   without breaking the cell rhythm:
       [ name | gf | ref         ]
       [           cta            ]
   The CTA is right-aligned to land on the same x as the head's
   right edge. */
@media (max-width: 720px) {
  .grades { padding-top: 56px; padding-bottom: 24px; }

  .grade-table-head {
    grid-template-columns: 104px 56px 1fr;
    padding: 10px 14px;
    font-size: 10px;
    letter-spacing: 0.04em;
  }
  .grade-table-head > div { padding: 0; white-space: nowrap; }
  /* Hide the empty 4th column header on mobile (CTA collapses to row 2). */
  .grade-table-head > div:nth-child(4) { display: none; }

  .grade-row {
    grid-template-columns: 104px 56px 1fr;
    grid-template-areas:
      'name gf ref'
      'cta  cta cta';
    align-items: stretch;
    padding: 0 14px 10px;
  }
  .grade-row > div { padding: 12px 0; }
  .grade-row > div:first-child,
  .grade-row > .grade-row-name { grid-area: name; padding-left: 0; }
  .grade-row > .grade-row-gf   { grid-area: gf; }
  .grade-row > .grade-row-ref  { grid-area: ref; padding-right: 0; }
  .grade-row > .grade-row-cta  {
    grid-area: cta;
    padding: 0 0 10px;
    justify-content: flex-end;
  }

  .grade-row-name {
    font-size: 13px;
    letter-spacing: 0;
    overflow: hidden;
    text-overflow: clip;
  }
  .grade-row-gf { font-size: 12px; }
  .grade-row-ref {
    font-size: 11px;
    line-height: 1.4;
    white-space: normal;
    overflow-wrap: anywhere;
  }
  .grade-row-cta > span:first-child {
    padding: 5px 12px;
    font-size: 10px;
    letter-spacing: 0.1em;
    /* Navy by default on mobile so it's visibly "tap me" without hover. */
    background: var(--accent-dark);
    color: var(--accent-on);
    border-color: var(--accent-dark);
  }
  .grade-row-cta-arrow { color: var(--accent-on); }
}