/* ---------------------------------------------------
   Textile 101 — Field Notes (BASICS)

   Site chrome (nav, project-header, hero, footer, back-to-top)
   all come straight from styles.css and its shared --black /
   --ink / --petrol-bright tokens plus Fraunces / IBM Plex Mono —
   this file only covers what's unique to this page: the on-page
   TOC, the nine topic sections, and their diagrams, grids, and
   native <details> reveals.

   Reading columns (headings + copy) match .project__body's
   22rem/46rem measure so body text lines up with every other
   Field Notes page. Diagrams and grids are NOT held to that
   46rem column — they're full section width (the same 6vw-gutter
   convention .hero/.grid/.footer already use sitewide), since a
   920-wide woven/knit diagram or a 4-up icon grid reads badly
   squeezed into a 46rem prose column.
--------------------------------------------------- */

/* ---------- On-page TOC (sits inside .project__hero) ---------- */
.tx-toc {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.tx-toc__label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-dim);
  margin-bottom: 1.1rem;
}

.tx-toc__list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.6rem 2rem;
}

.tx-toc__list li {
  font-size: 13px;
}

.tx-toc__list a {
  color: var(--ink-dim);
  border-bottom: 1px solid transparent;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.tx-toc__list a:hover {
  color: var(--petrol-bright);
  border-color: var(--petrol-bright);
}

.tx-toc__list .n {
  color: var(--petrol-bright);
  margin-right: 0.5em;
}

/* ---------- Topic sections ---------- */
.tx-topic {
  padding: 5.5rem 6vw;
  border-top: 1px solid var(--line);
}

.tx-topic:first-of-type {
  border-top: none;
}

.tx-topic-head {
  display: grid;
  grid-template-columns: minmax(0, 22rem) minmax(0, 46rem);
  gap: 4vw;
  align-items: start;
}

.tx-topic-head h2 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(1.7rem, 3vw, 2.5rem);
  line-height: 1.15;
  letter-spacing: -0.01em;
  text-transform: uppercase;
  color: var(--ink);
  position: sticky;
  top: 2.5rem;
}

.tx-topic-copy p {
  max-width: 62ch;
  color: var(--ink);
  font-size: 14px;
  line-height: 1.75;
  margin: 0 0 1.1rem;
}

.tx-topic-copy p:last-child {
  margin-bottom: 0;
}

.tx-topic-copy .muted {
  color: var(--ink-dim);
}

.tx-topic-copy .project__list {
  margin-top: 1.25rem;
}

/* ---------- Diagram blocks (warp/weft, weft/warp knit) ---------- */
.tx-diagram {
  margin-top: 3rem;
  padding: 2.5rem clamp(1rem, 4vw, 2.5rem);
  border: 1px solid var(--line);
  background: rgba(233, 236, 236, 0.02);
}

.tx-diagram svg {
  display: block;
  width: 100%;
  height: auto;
}

.tx-diagram__caption {
  margin-top: 1.1rem;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink-dim);
  text-align: center;
}

.tx-diagram__caption .accent {
  color: var(--petrol-bright);
}

.axis-label {
  font-family: var(--mono);
  font-size: 13px;
  fill: var(--ink-dim);
  letter-spacing: 0.06em;
}

/* draw-on animation shared by the warp/weft weave and weft/warp knit
   diagrams — a continuous strand traces its path, holds, then resets. */
.yarn-path,
.weave-path {
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.yarn-path {
  stroke-dasharray: 900;
  stroke-dashoffset: 900;
  animation: tx-draw 5.4s ease-in-out infinite;
}

.weave-path {
  stroke-dasharray: 700;
  stroke-dashoffset: 700;
  animation: tx-draw 4.2s ease-in-out infinite;
}

.yarn-path.delay1 { animation-delay: 0.22s; }
.yarn-path.delay2 { animation-delay: 0.45s; }
.yarn-path.delay3 { animation-delay: 0.68s; }
.yarn-path.delay4 { animation-delay: 0.9s; }

/* weft/warp knit: two generated panels (tools/knit-diagram/), side by side, stacked under 560px */
.tx-diagram__panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.tx-diagram__panels .tx-panel:first-child { padding-right: 2rem; }

.tx-diagram__panels .tx-panel + .tx-panel {
  border-left: 1px solid var(--line);
  padding-left: 2rem;
}

@media (max-width: 560px) {
  .tx-diagram__panels { grid-template-columns: 1fr; gap: 1.5rem 0; }
  .tx-diagram__panels .tx-panel:first-child { padding-right: 0; }
  .tx-diagram__panels .tx-panel + .tx-panel {
    border-left: 0;
    padding-left: 0;
    border-top: 1px solid var(--line);
    padding-top: 1.5rem;
  }
}

@keyframes tx-draw {
  0%   { stroke-dashoffset: 900; }
  45%  { stroke-dashoffset: 0; }
  80%  { stroke-dashoffset: 0; }
  100% { stroke-dashoffset: -900; }
}

@media (prefers-reduced-motion: reduce) {
  .yarn-path,
  .weave-path {
    animation: none;
    stroke-dashoffset: 0;
  }
}

/* ---------- Fiber -> yarn -> fabric chain ---------- */
.tx-chain {
  margin-top: 3rem;
  display: flex;
  align-items: center;
  gap: 0;
}

.tx-chain-node {
  flex: 1;
  text-align: center;
  padding: 2.25rem 1rem;
  border: 1px solid var(--line);
}

.tx-chain-node .icon {
  margin: 0 auto 1.1rem;
  width: 44px;
  height: 44px;
}

.tx-chain-node .label {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.25rem;
  color: var(--ink);
}

.tx-chain-node .sub {
  margin-top: 0.5rem;
  font-size: 12px;
  color: var(--ink-dim);
}

.tx-chain-arrow {
  flex: 0 0 auto;
  width: 48px;
  display: flex;
  justify-content: center;
  color: var(--petrol-bright);
  font-size: 20px;
}

@media (max-width: 700px) {
  .tx-chain {
    flex-direction: column;
  }
  .tx-chain-arrow {
    transform: rotate(90deg);
  }
}

/* ---------- Icon grids (fiber families, cross-sections, yarn types) ---------- */
.tx-icon-grid {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.tx-icon-grid.cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

.tx-icon-cell {
  background: var(--black);
  padding: 1.9rem 1.1rem;
  text-align: center;
}

.tx-icon-cell svg {
  width: 52px;
  height: 52px;
  margin-bottom: 1rem;
}

.tx-icon-cell .name {
  font-size: 13px;
  letter-spacing: 0.03em;
  color: var(--ink);
  margin-bottom: 0.4rem;
}

.tx-icon-cell .desc {
  font-size: 12px;
  color: var(--ink-dim);
  line-height: 1.6;
}

@media (max-width: 860px) {
  .tx-icon-grid,
  .tx-icon-grid.cols-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .tx-icon-grid,
  .tx-icon-grid.cols-3 {
    grid-template-columns: 1fr;
  }
}

/* ---------- Definition list (reading a yarn spec) ---------- */
.tx-def-list {
  margin-top: 2.5rem;
  display: grid;
  gap: 1.5rem;
}

.tx-def-list dt {
  font-size: 14px;
  color: var(--ink);
  margin-bottom: 0.25rem;
}

.tx-def-list dt .accent {
  color: var(--petrol-bright);
}

.tx-def-list dd {
  margin: 0;
  font-size: 13.5px;
  color: var(--ink-dim);
  max-width: 60ch;
}

/* ---------- Decode-a-yarn-spec interactive ---------- */
.tx-decode {
  margin-top: 3.5rem;
}

.tx-decode__intro {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--petrol-bright);
  margin-bottom: 1.25rem;
}

details.tx-decode-card {
  border: 1px solid var(--line);
  margin-bottom: -1px;
}

details.tx-decode-card summary {
  cursor: pointer;
  list-style: none;
  padding: 1.4rem 1.6rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.25rem;
  font-size: 14.5px;
  color: var(--ink);
}

details.tx-decode-card summary::-webkit-details-marker {
  display: none;
}

details.tx-decode-card summary .reveal-cta {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ink-dim);
  white-space: nowrap;
  transition: color 0.15s ease;
}

details.tx-decode-card[open] summary .reveal-cta {
  color: var(--petrol-bright);
}

details.tx-decode-card[open] summary .reveal-cta::before {
  content: "\2212 HIDE";
}

details.tx-decode-card:not([open]) summary .reveal-cta::before {
  content: "+ REVEAL";
}

.tx-decode-answer {
  padding: 0.25rem 1.6rem 1.6rem;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

.tx-decode-answer .field {
  font-size: 12px;
}

.tx-decode-answer .field .k {
  color: var(--ink-dim);
  letter-spacing: 0.06em;
  display: block;
  margin-bottom: 0.25rem;
}

.tx-decode-answer .field .v {
  color: var(--petrol-bright);
}

@media (max-width: 700px) {
  .tx-decode-answer {
    grid-template-columns: 1fr 1fr;
  }
}

/* ---------- Three-way compare (wovens / knits / nonwovens) ---------- */
.tx-tri-compare {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid var(--line);
}

.tx-tri-compare .col {
  padding: 1.9rem 1.6rem;
}

.tx-tri-compare .col + .col {
  border-left: 1px solid var(--line);
}

.tx-tri-compare h3 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.1rem;
  color: var(--ink);
  margin-bottom: 0.75rem;
}

.tx-tri-compare p {
  font-size: 13px;
  color: var(--ink-dim);
  margin: 0;
  line-height: 1.7;
}

@media (max-width: 860px) {
  .tx-tri-compare {
    grid-template-columns: 1fr;
  }
  .tx-tri-compare .col + .col {
    border-left: none;
    border-top: 1px solid var(--line);
  }
}

/* ---------- "Go deeper" accordion (structural variations) ---------- */
.tx-advanced {
  margin-top: 3.5rem;
}

details.tx-advanced-panel {
  border-top: 1px solid var(--line);
}

details.tx-advanced-panel summary {
  cursor: pointer;
  list-style: none;
  padding: 1.4rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-dim);
  transition: color 0.15s ease;
}

details.tx-advanced-panel summary:hover {
  color: var(--ink);
}

details.tx-advanced-panel summary::-webkit-details-marker {
  display: none;
}

details.tx-advanced-panel summary .plus {
  color: var(--petrol-bright);
  font-size: 16px;
  transition: transform 0.15s ease;
}

details.tx-advanced-panel[open] summary .plus {
  transform: rotate(45deg);
}

.tx-advanced-body {
  padding: 0.5rem 0 2.25rem;
}

.tx-struct-groups {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2.25rem;
}

.tx-struct-groups h4 {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--petrol-bright);
  font-weight: 500;
  margin: 0 0 0.9rem;
}

.tx-struct-groups ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.6rem;
}

.tx-struct-groups li {
  font-size: 12.5px;
  color: var(--ink-dim);
  line-height: 1.6;
}

.tx-struct-groups li strong {
  color: var(--ink);
  font-weight: 500;
}

@media (max-width: 700px) {
  .tx-struct-groups {
    grid-template-columns: 1fr;
  }
}

/* ---------- Wovens-vs-knits / weft-vs-warp compare strip ---------- */
.tx-compare {
  margin-top: 3rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  border: 1px solid var(--line);
}

.tx-compare .col {
  padding: 1.9rem;
}

.tx-compare .col + .col {
  border-left: 1px solid var(--line);
}

.tx-compare h3 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.1rem;
  color: var(--ink);
  margin-bottom: 1rem;
}

.tx-compare ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.6rem;
  font-size: 13.5px;
  color: var(--ink-dim);
}

.tx-compare li {
  padding-left: 1rem;
  position: relative;
}

.tx-compare li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5rem;
  width: 5px;
  height: 5px;
  background: var(--petrol-bright);
  border-radius: 50%;
}

@media (max-width: 700px) {
  .tx-compare {
    grid-template-columns: 1fr;
  }
  .tx-compare .col + .col {
    border-left: none;
    border-top: 1px solid var(--line);
  }
}

/* ---------- Responsive: topic head + TOC ---------- */
@media (max-width: 860px) {
  .tx-toc__list {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 800px) {
  .tx-topic-head {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .tx-topic-head h2 {
    position: static;
  }
}

@media (max-width: 600px) {
  .tx-toc__list {
    grid-template-columns: 1fr;
  }
  .tx-topic {
    padding: 4rem 6vw;
  }
}