/* cexpal · blueprint sheet */

:root {
  --sheet: #ffffff;
  --ink: #0b1a4a;
  --graphite: #2d3a5c;
  --graphite-2: #55627f;
  --trace: #1d4ed8;
  --trace-deep: #1639a8;
  --wash: #eef3ff;
  --wash-2: #f6f9ff;
  --hair: #d5def2;
  --hair-2: #e6ecf8;
  --redline: #c2410c;
  --redline-wash: #fff6f0;
  --grid-minor: rgba(29, 78, 216, .065);
  --grid-major: rgba(29, 78, 216, .15);

  --f-head: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --f-body: -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --f-mono: "Martian Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --measure: 42.5rem;
  --rail: 17.5rem;
  --pin: 1.5rem;
}

*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  overflow-x: clip;
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

body {
  margin: 0;
  background: var(--sheet);
  color: var(--graphite);
  font: 400 1.0625rem/1.85 var(--f-body);
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; }
a { color: var(--trace); text-decoration-thickness: 1px; text-underline-offset: .22em; }
a:hover { color: var(--trace-deep); text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--trace); outline-offset: 3px; }

.cp-skip {
  position: absolute; left: 1rem; top: -3rem; z-index: 20;
  background: var(--ink); color: #fff; padding: .4rem .8rem; font-size: .875rem;
}
.cp-skip:focus { top: .75rem; }

/* ---------- masthead ---------- */

.cp-mast {
  border-bottom: 1px solid var(--hair);
  background: var(--sheet);
  position: relative;
  z-index: 2;
}
.cp-mast::after {
  content: "";
  position: absolute; left: 0; right: 0; bottom: -4px;
  height: 3px;
  background: linear-gradient(90deg, var(--trace) 0 6rem, transparent 6rem);
}
.cp-mast__in {
  max-width: 69.5rem;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2.5rem);
  min-height: 4.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.cp-mark {
  display: inline-flex; align-items: center; gap: .6rem;
  color: var(--ink); text-decoration: none;
}
.cp-mark:hover { color: var(--ink); }
.cp-mark__glyph { color: var(--trace); flex: none; }
.cp-mark__name { font: 700 1.2rem/1 var(--f-head); letter-spacing: .02em; }

.cp-nav { display: flex; gap: clamp(.9rem, 3vw, 2rem); }
.cp-nav a {
  position: relative;
  color: var(--graphite);
  text-decoration: none;
  font-size: .95rem;
  padding: .35rem 0;
}
.cp-nav a::after {
  content: "";
  position: absolute; left: 0; right: 0; bottom: -2px;
  height: 2px; background: var(--trace);
  transform: scaleX(0); transform-origin: left;
  transition: transform .2s ease;
}
.cp-nav a:hover::after,
.cp-nav a[aria-current="page"]::after,
[data-page="about"] .cp-nav [data-nav="about"]::after,
[data-page="contact"] .cp-nav [data-nav="contact"]::after { transform: scaleX(1); }
.cp-nav a[aria-current="page"],
[data-page="about"] .cp-nav [data-nav="about"],
[data-page="contact"] .cp-nav [data-nav="contact"] { color: var(--ink); font-weight: 600; }

/* ---------- main sheet grid ---------- */

.cp-main {
  display: grid;
  grid-template-columns:
    [full-start] minmax(1.25rem, 1fr)
    [main-start] minmax(0, 27rem)
    [mid] minmax(0, calc(var(--measure) - 27rem))
    [main-end] minmax(2.5rem, 4.5rem)
    [rail-start] var(--rail)
    [rail-end] minmax(1.25rem, 1fr)
    [full-end];
  row-gap: 0;
  counter-reset: sec dwg;
}
.cp-doc { display: contents; }
.cp-doc > * { grid-column: main-start / main-end; min-width: 0; }

/* first screen: blueprint grid lives only here */
.cp-band {
  grid-row: 1;
  grid-column: full-start / full-end;
  background-color: var(--wash-2);
  background-image:
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    linear-gradient(var(--grid-minor) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-minor) 1px, transparent 1px);
  background-size: 7.5rem 7.5rem, 7.5rem 7.5rem, 1.5rem 1.5rem, 1.5rem 1.5rem;
  background-position: -1px -1px;
  border-bottom: 1px solid var(--hair);
}

.cp-doc > header[data-part="hero"] {
  grid-row: 1;
  grid-column: main-start / mid;
  align-self: center;
  position: relative;
  z-index: 1;
  padding: clamp(2.5rem, 6vw, 4.5rem) 0 clamp(2.5rem, 5vw, 4rem);
}
[data-part="kicker"] {
  display: inline-flex; align-items: center; gap: .75rem;
  margin: 0 0 1.25rem;
  font: 500 .75rem/1.4 var(--f-mono);
  letter-spacing: .08em;
  color: var(--trace);
}
[data-part="kicker"]::before {
  content: "";
  width: 2.75rem; height: 9px;
  border-inline: 1px solid var(--trace);
  background: linear-gradient(var(--trace), var(--trace)) center / 100% 1px no-repeat;
}
header[data-part="hero"] h1 {
  margin: 0 0 1.25rem;
  font: 700 clamp(1.75rem, 1.1rem + 2.2vw, 2.45rem)/1.28 var(--f-head);
  letter-spacing: -.005em;
  color: var(--ink);
  text-wrap: pretty;
}
[data-part="dek"] {
  margin: 0 0 1.6rem;
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--graphite);
}
[data-part="meta"] {
  margin: 0;
  display: inline-block;
  padding: .55rem .85rem .55rem 2.1rem;
  border: 1px solid var(--trace);
  background: var(--sheet);
  font-size: .875rem;
  line-height: 1.65;
  font-variant-numeric: tabular-nums;
  color: var(--ink);
  position: relative;
}
[data-part="meta"]::before {
  content: "";
  position: absolute; left: .8rem; top: .95rem;
  width: .55rem; height: .55rem;
  border: 1.5px solid var(--trace);
  transform: rotate(45deg);
}

.cp-plate {
  grid-row: 1;
  grid-column: mid / full-end;
  align-self: center;
  position: relative;
  z-index: 1;
  margin: 3.25rem clamp(1.25rem, 4vw, 4rem) 3.25rem 3rem;
}
.cp-plate img {
  display: block; width: 100%; height: auto;
  border: 1px solid var(--trace);
  background: var(--sheet);
}
.cp-plate::before,
.cp-plate::after {
  content: "";
  position: absolute;
  border-color: var(--trace);
  border-style: solid;
  opacity: .75;
}
.cp-plate::before {
  left: 0; right: 0; top: -1.3rem; height: 9px;
  border-width: 0 1px;
  background: linear-gradient(var(--trace), var(--trace)) center / 100% 1px no-repeat;
}
.cp-plate::after {
  top: 0; bottom: 0; left: -1.3rem; width: 9px;
  border-width: 1px 0;
  background: linear-gradient(var(--trace), var(--trace)) center / 1px 100% no-repeat;
}

/* ---------- rail: title block + index ---------- */

.cp-rail {
  grid-column: rail-start / rail-end;
  grid-row: 2 / span 40;
  margin-top: 3.5rem;
}
.cp-tb {
  position: sticky;
  top: 1.5rem;
  max-height: calc(100vh - 3rem);
  overflow: auto;
  border: 1px solid var(--ink);
  background: var(--sheet);
}
.cp-tb__head {
  display: flex; align-items: center; justify-content: space-between;
  padding: .7rem .95rem;
  border-bottom: 1px solid var(--ink);
}
.cp-tb__label {
  font: 500 .72rem/1 var(--f-mono);
  letter-spacing: .14em;
  color: var(--ink);
}
.cp-tb__fold {
  font: 500 .72rem/1 var(--f-mono);
  color: var(--trace);
  background: none;
  border: 1px solid var(--trace);
  padding: .4rem .6rem;
  cursor: pointer;
}
.cp-idx { list-style: none; margin: 0; padding: 0; counter-reset: idx; }
.cp-idx__i { counter-increment: idx; }
.cp-idx__i a {
  display: grid;
  grid-template-columns: 2.1rem 1fr;
  align-items: baseline;
  padding: .55rem .95rem .55rem .8rem;
  border-bottom: 1px solid var(--hair-2);
  font-size: .86rem;
  line-height: 1.5;
  color: var(--graphite);
  text-decoration: none;
  box-shadow: inset 0 0 0 var(--trace);
  transition: background-color .15s, box-shadow .15s, color .15s;
}
.cp-idx__i a::before {
  content: counter(idx, decimal-leading-zero);
  font: 500 .68rem/1 var(--f-mono);
  color: var(--trace);
}
.cp-idx__i a:hover { background: var(--wash-2); color: var(--ink); }
.cp-idx__i a[aria-current="true"] {
  background: var(--wash);
  color: var(--ink);
  font-weight: 600;
  box-shadow: inset 3px 0 0 var(--trace);
}
.cp-tb__foot {
  display: grid; grid-template-columns: 1fr auto;
  padding: .6rem .95rem;
  font: 400 .7rem/1.4 var(--f-mono);
  color: var(--graphite-2);
}
.cp-tb__foot time { color: var(--ink); }
.cp-meter { height: 3px; background: var(--hair-2); }
.cp-meter i {
  display: block; height: 100%; width: 0;
  background: var(--trace);
  transform-origin: left;
}

/* ---------- body copy ---------- */

.cp-doc > section {
  counter-increment: sec;
  margin-top: 4.5rem;
  scroll-margin-top: 1.5rem;
}
.cp-doc > header + section { margin-top: 3.5rem; }

.cp-doc h2 {
  display: grid;
  grid-template-columns: 2.9rem 1fr;
  gap: 1rem;
  align-items: center;
  margin: 0 0 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--hair);
  font: 700 clamp(1.35rem, 1.1rem + .9vw, 1.7rem)/1.4 var(--f-head);
  color: var(--ink);
  position: relative;
}
.cp-doc h2::before {
  content: counter(sec, decimal-leading-zero);
  display: grid; place-items: center;
  width: 2.9rem; height: 2.9rem;
  border: 1.5px solid var(--trace);
  border-radius: 50%;
  font: 500 .8rem/1 var(--f-mono);
  color: var(--trace);
  background:
    linear-gradient(var(--trace), var(--trace)) center 72% / 55% 1px no-repeat,
    var(--sheet);
  padding-bottom: .35rem;
}
.cp-doc h2::after {
  content: "";
  position: absolute; left: 0; bottom: -1px;
  width: 2.9rem; height: 2px; background: var(--trace);
}
.cp-doc h3 {
  margin: 2.5rem 0 .9rem;
  font: 700 1.18rem/1.5 var(--f-head);
  color: var(--ink);
  padding-left: 1rem;
  position: relative;
}
.cp-doc h3::before {
  content: "";
  position: absolute; left: 0; top: .32em;
  width: 4px; height: 1em;
  background: var(--trace);
}
.cp-doc p { margin: 0 0 1.15em; }
.cp-doc strong {
  color: var(--ink);
  background: linear-gradient(transparent 64%, rgba(29, 78, 216, .13) 64%);
}
.cp-doc ul { margin: 0 0 1.3em; padding-left: 0; list-style: none; }
.cp-doc ul > li { position: relative; padding-left: 1.4rem; margin-bottom: .55em; }
.cp-doc ul > li::before {
  content: "";
  position: absolute; left: .2rem; top: .78em;
  width: .45rem; height: .45rem;
  border: 1.5px solid var(--trace);
}

/* tables: schedule style */
.cp-doc table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0 1.6rem;
  font-size: .94rem;
  line-height: 1.7;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}
.cp-doc th {
  text-align: left;
  font: 500 .72rem/1.5 var(--f-mono);
  letter-spacing: .06em;
  color: var(--trace);
  padding: .7rem .8rem;
  border-bottom: 1px solid var(--ink);
  background: var(--wash-2);
  white-space: nowrap;
}
.cp-doc td {
  padding: .75rem .8rem;
  border-bottom: 1px solid var(--hair-2);
  vertical-align: top;
}
.cp-doc td:first-child { color: var(--ink); font-weight: 600; }
.cp-doc tbody tr:hover td { background: var(--wash-2); }

/* definition list */
.cp-doc dl { margin: 1.25rem 0 1.5rem; border-top: 1px solid var(--hair); }
.cp-doc dt {
  font: 700 1.02rem/1.5 var(--f-head);
  color: var(--ink);
  padding-top: 1rem;
}
.cp-doc dd {
  margin: .35rem 0 0;
  padding: 0 0 1rem 1rem;
  border-left: 2px solid var(--wash);
  border-bottom: 1px solid var(--hair);
}

/* steps */
ol[data-part="steps"] {
  list-style: none;
  margin: 1.1rem 0 1.5rem;
  padding: 0;
  counter-reset: stp;
}
ol[data-part="steps"] > li {
  counter-increment: stp;
  position: relative;
  padding: .05rem 0 1.05rem 3rem;
  min-height: 2.6rem;
}
ol[data-part="steps"] > li::before {
  content: counter(stp, decimal-leading-zero);
  position: absolute; left: 0; top: .1rem;
  width: 1.9rem; height: 1.9rem;
  display: grid; place-items: center;
  border: 1px solid var(--trace);
  background: var(--sheet);
  font: 500 .68rem/1 var(--f-mono);
  color: var(--trace);
  z-index: 1;
}
ol[data-part="steps"] > li::after {
  content: "";
  position: absolute; left: .95rem; top: 2rem; bottom: 0;
  border-left: 1px dashed var(--trace);
  opacity: .55;
}
ol[data-part="steps"] > li:last-child::after { display: none; }
ol[data-part="steps"] ul { margin: .6rem 0 .2rem; }
ol[data-part="steps"] ul li {
  font: 400 .82rem/1.6 var(--f-mono);
  color: var(--ink);
  margin-bottom: .3rem;
  overflow-wrap: anywhere;
}

/* notes */
[data-part="note"],
[data-part="warn"] {
  position: relative;
  margin: 1.6rem 0 1.8rem;
  padding: 1.15rem 1.3rem 1.15rem 1.3rem;
  font-size: 1rem;
  line-height: 1.8;
}
[data-part="note"] > :last-child,
[data-part="warn"] > :last-child { margin-bottom: 0; }
[data-part="note"] {
  background: var(--wash);
  border-left: 3px solid var(--trace);
}
[data-part="warn"] {
  background: var(--redline-wash);
  border: 1px dashed var(--redline);
  border-left: 3px solid var(--redline);
  padding-top: 1.7rem;
}
[data-part="warn"]::before {
  content: "注意";
  position: absolute; left: 1.3rem; top: -.7rem;
  padding: .15rem .55rem;
  background: var(--redline);
  color: #fff;
  font: 500 .7rem/1.4 var(--f-mono);
  letter-spacing: .12em;
}
[data-part="warn"] strong { color: var(--redline); background: none; }

/* ---------- drawings: screenshot + numbered pins + legend ---------- */

figure[data-part="shot"] {
  counter-increment: dwg;
  position: relative;
  margin: 2rem 0 2.25rem;
  padding: .9rem .9rem 0;
  border: 1px solid var(--trace);
  background: var(--wash-2);
}
figure[data-part="shot"]::before,
figure[data-part="shot"]::after {
  content: "";
  position: absolute;
  width: .85rem; height: .85rem;
  border: 0 solid var(--trace);
}
figure[data-part="shot"]::before { left: -.45rem; top: -.45rem; border-width: 2px 0 0 2px; }
figure[data-part="shot"]::after { right: -.45rem; top: -.45rem; border-width: 2px 2px 0 0; }

figure[data-part="shot"] > img,
.cp-pinbox > img {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 0 auto;
  border: 1px solid var(--hair);
  background: var(--sheet);
}
.cp-pinbox {
  position: relative;
  display: block;
  width: fit-content;
  max-width: 100%;
  margin: 0 auto;
}
figure[data-part="shot"] figcaption {
  display: flex;
  gap: .8rem;
  align-items: baseline;
  margin: .9rem -.9rem 0;
  padding: .7rem .9rem;
  border-top: 1px solid var(--trace);
  background: var(--sheet);
  font-size: .86rem;
  line-height: 1.6;
  color: var(--graphite-2);
}
figure[data-part="shot"] figcaption::before {
  content: "图 " counter(dwg, decimal-leading-zero);
  flex: none;
  padding: .2rem .5rem;
  background: var(--trace);
  color: #fff;
  font: 500 .68rem/1.4 var(--f-mono);
  letter-spacing: .04em;
  white-space: nowrap;
}

.cp-pin {
  position: absolute;
  width: var(--pin); height: var(--pin);
  margin: calc(var(--pin) / -2) 0 0 calc(var(--pin) / -2);
  padding: 0;
  display: grid; place-items: center;
  border: 0;
  border-radius: 50%;
  background: var(--trace);
  color: #fff;
  font: 500 .66rem/1 var(--f-mono);
  box-shadow: 0 0 0 2px #fff, 0 0 0 3.5px var(--trace), 0 3px 10px rgba(11, 26, 74, .3);
  cursor: pointer;
  transition: transform .18s ease, background-color .18s;
  animation: cp-drop .45s cubic-bezier(.2, .9, .3, 1.3) both;
  animation-delay: calc(var(--i, 0) * 90ms);
}
.cp-pin::after {
  content: "";
  position: absolute; inset: -7px;
  border-radius: 50%;
  border: 1.5px solid var(--trace);
  opacity: 0;
  transform: scale(.6);
  transition: opacity .2s, transform .2s;
}
.cp-pin:hover,
.cp-pin.is-lit { transform: scale(1.18); background: var(--ink); }
.cp-pin.is-lit::after { opacity: .7; transform: scale(1); }
@keyframes cp-drop {
  from { opacity: 0; transform: translateY(-6px) scale(.6); }
  to { opacity: 1; transform: none; }
}

ol[data-part="legend"] {
  list-style: none;
  counter-reset: leg;
  margin: -2.25rem 0 2.5rem;
  padding: 0 0 .4rem;
  border: 1px solid var(--trace);
  border-top: 0;
  background: var(--sheet);
  position: relative;
}
ol[data-part="legend"]::before {
  content: "图 " counter(dwg, decimal-leading-zero) " 图例";
  display: block;
  padding: .55rem 1rem;
  border-top: 1px dashed var(--trace);
  border-bottom: 1px solid var(--hair-2);
  background: var(--wash-2);
  font: 500 .68rem/1.4 var(--f-mono);
  letter-spacing: .1em;
  color: var(--trace);
}
ol[data-part="legend"] > li {
  counter-increment: leg;
  position: relative;
  display: grid;
  grid-template-columns: 1.75rem 1fr;
  gap: .85rem;
  padding: .7rem 1rem;
  font-size: .95rem;
  line-height: 1.72;
  border-bottom: 1px solid var(--hair-2);
  transition: background-color .18s;
}
ol[data-part="legend"] > li:last-child { border-bottom: 0; }
ol[data-part="legend"] > li::before {
  content: counter(leg);
  width: 1.5rem; height: 1.5rem;
  margin-top: .12rem;
  display: grid; place-items: center;
  border-radius: 50%;
  border: 1.5px solid var(--trace);
  color: var(--trace);
  font: 500 .66rem/1 var(--f-mono);
  transition: background-color .18s, color .18s;
}
ol[data-part="legend"].cp-has-pins > li { cursor: pointer; }
ol[data-part="legend"] > li.is-lit { background: var(--wash); }
ol[data-part="legend"] > li.is-lit::before { background: var(--ink); border-color: var(--ink); color: #fff; }

/* ---------- referral block ---------- */

aside[data-part="cta"] {
  display: grid;
  grid-template-columns: minmax(0, 15.5rem) minmax(0, 1fr);
  margin: 3.5rem 0 1rem;
  border: 2px solid var(--trace);
  background: var(--sheet);
  position: relative;
}
aside[data-part="cta"] > p { margin: 0; }
aside[data-part="cta"] > p:nth-of-type(1) {
  grid-row: 1 / 3;
  padding: 1.4rem 1.3rem;
  background: var(--ink);
  color: #fff;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: .6rem;
}
aside[data-part="cta"] > p:nth-of-type(1) strong {
  background: none;
  color: #fff;
  font: 700 1.3rem/1.45 var(--f-head);
}
.cp-code__k {
  display: block;
  font: 500 .7rem/1.4 var(--f-mono);
  letter-spacing: .12em;
  color: #a9bdf5;
  margin-bottom: .55rem;
}
.cp-code__v {
  display: block;
  font: 500 1.85rem/1.1 var(--f-mono);
  letter-spacing: .06em;
  color: #fff;
  padding: .7rem .6rem;
  border: 1px dashed rgba(255, 255, 255, .55);
  text-align: center;
  user-select: all;
}
.cp-copy {
  align-self: stretch;
  font: 500 .78rem/1 var(--f-mono);
  letter-spacing: .06em;
  color: var(--ink);
  background: #fff;
  border: 0;
  padding: .7rem .8rem;
  cursor: pointer;
  transition: background-color .15s;
}
.cp-copy:hover { background: var(--wash); }
.cp-copy.is-done { background: #dbe7ff; color: var(--trace-deep); }
aside[data-part="cta"] > p:nth-of-type(2) {
  padding: 1.35rem 1.5rem .2rem;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--graphite);
}
aside[data-part="cta"] > p:nth-of-type(3) { padding: .9rem 1.5rem 1.4rem; }
aside[data-part="cta"] a[data-cta] {
  display: inline-flex;
  align-items: center;
  gap: .9rem;
  padding: .85rem 1.4rem .85rem 1.5rem;
  background: var(--trace);
  color: #fff;
  font: 700 1.05rem/1.2 var(--f-head);
  text-decoration: none;
  box-shadow: 4px 4px 0 var(--ink);
  transition: transform .15s, box-shadow .15s, background-color .15s;
}
aside[data-part="cta"] a[data-cta]::after {
  content: "";
  width: 1.4rem; height: .7rem;
  background:
    linear-gradient(#fff, #fff) left center / 100% 1.5px no-repeat;
  clip-path: polygon(0 45%, 75% 45%, 75% 0, 100% 50%, 75% 100%, 75% 55%, 0 55%);
  background-color: #fff;
}
aside[data-part="cta"] a[data-cta]:hover {
  background: var(--trace-deep);
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 var(--ink);
  color: #fff;
}
aside[data-part="cta"] > p:nth-of-type(4) {
  grid-column: 1 / -1;
  padding: .95rem 1.5rem;
  border-top: 1px dashed var(--trace);
  background: var(--wash-2);
  font-size: .95rem;
  line-height: 1.75;
  color: var(--graphite);
}

/* ---------- FAQ ---------- */

#faq { counter-reset: q; }
#faq details {
  counter-increment: q;
  border-bottom: 1px solid var(--hair);
}
#faq details:first-of-type { border-top: 1px solid var(--ink); }
#faq summary {
  list-style: none;
  display: grid;
  grid-template-columns: 2.6rem 1fr 1.6rem;
  align-items: start;
  gap: .4rem;
  padding: 1.05rem 0;
  cursor: pointer;
  font: 700 1.04rem/1.6 var(--f-head);
  color: var(--ink);
}
#faq summary::-webkit-details-marker { display: none; }
#faq summary::before {
  content: "Q" counter(q, decimal-leading-zero);
  font: 500 .68rem/2.4 var(--f-mono);
  color: var(--trace);
}
#faq summary::after {
  content: "";
  width: 1.4rem; height: 1.4rem;
  margin-top: .15rem;
  border: 1px solid var(--trace);
  background:
    linear-gradient(var(--trace), var(--trace)) center / .6rem 1.5px no-repeat,
    linear-gradient(var(--trace), var(--trace)) center / 1.5px .6rem no-repeat;
  transition: background-color .15s;
}
#faq details[open] summary::after {
  background:
    linear-gradient(#fff, #fff) center / .6rem 1.5px no-repeat,
    var(--trace);
}
#faq summary:hover { color: var(--trace-deep); }
#faq details > :not(summary) {
  margin: 0 2rem 1.2rem 3rem;
  color: var(--graphite);
}

/* ---------- footer: title block ---------- */

.cp-foot {
  margin-top: 6rem;
  background: var(--ink);
  color: #c4d1f3;
  font-size: .9rem;
  line-height: 1.7;
}
.cp-foot a { color: #fff; text-decoration-color: rgba(255, 255, 255, .4); }
.cp-foot a:hover { color: #fff; text-decoration-color: #fff; }
.cp-foot__in {
  max-width: 69.5rem;
  margin: 0 auto;
  padding: 2.75rem clamp(1rem, 4vw, 2.5rem) 2rem;
  display: grid;
  grid-template-columns: 1.4fr 1.2fr 1fr;
}
.cp-foot__cell {
  padding: 1rem 1.25rem;
  border: 1px solid rgba(255, 255, 255, .14);
  margin: 0 0 -1px -1px;
}
.cp-foot__id { display: flex; flex-direction: column; gap: .35rem; }
.cp-foot__name { font: 700 1.15rem/1.3 var(--f-head); color: #fff; }
.cp-foot__links { display: flex; flex-wrap: wrap; gap: .4rem 1.25rem; align-content: center; }
.cp-foot__k {
  display: block;
  font: 500 .66rem/1.6 var(--f-mono);
  letter-spacing: .12em;
  color: #8ea6e8;
}
.cp-foot__risk { grid-column: 1 / -1; color: #e3e9fb; }
.cp-foot__copy {
  grid-column: 1 / -1;
  margin: 1.25rem 0 0;
  font: 400 .72rem/1.5 var(--f-mono);
  color: #8ea6e8;
}

/* ---------- sub pages ---------- */

.cp-folio {
  max-width: 48rem;
  margin: 0 auto;
  padding: clamp(2rem, 5vw, 3.5rem) clamp(1rem, 4vw, 2rem) 0;
}
.cp-folio__sheet {
  position: relative;
  border: 1px solid var(--trace);
  padding: clamp(1.5rem, 4vw, 3rem);
  background: var(--sheet);
}
.cp-folio__sheet::before,
.cp-folio__sheet::after {
  content: "";
  position: absolute;
  width: 1rem; height: 1rem;
  border: 0 solid var(--trace);
}
.cp-folio__sheet::before { left: -.5rem; top: -.5rem; border-width: 2px 0 0 2px; }
.cp-folio__sheet::after { right: -.5rem; bottom: -.5rem; border-width: 0 2px 2px 0; }
.cp-folio h1 {
  margin: 0 0 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--ink);
  font: 700 clamp(1.6rem, 1.2rem + 1.5vw, 2.1rem)/1.35 var(--f-head);
  color: var(--ink);
}
.cp-folio h2 {
  margin: 2.25rem 0 .8rem;
  font: 700 1.2rem/1.5 var(--f-head);
  color: var(--ink);
  padding-left: 1rem;
  position: relative;
}
.cp-folio h2::before {
  content: "";
  position: absolute; left: 0; top: .3em;
  width: 4px; height: 1em; background: var(--trace);
}
.cp-folio p { margin: 0 0 1.1em; }
.cp-folio ul { margin: 0 0 1.3em; padding: 0; list-style: none; }
.cp-folio li { position: relative; padding-left: 1.4rem; margin-bottom: .6em; }
.cp-folio li::before {
  content: "";
  position: absolute; left: .2rem; top: .78em;
  width: .45rem; height: .45rem;
  border: 1.5px solid var(--trace);
}
.cp-folio strong { color: var(--ink); }
.cp-folio__back { margin: 1.75rem 0 0; font-size: .95rem; }
.cp-folio__back a::before { content: "← "; }

/* ---------- 404 ---------- */

.cp-void {
  min-height: 62vh;
  display: grid;
  place-items: center;
  padding: 3rem 1rem;
  background-color: var(--wash-2);
  background-image:
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    linear-gradient(var(--grid-minor) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-minor) 1px, transparent 1px);
  background-size: 7.5rem 7.5rem, 7.5rem 7.5rem, 1.5rem 1.5rem, 1.5rem 1.5rem;
}
.cp-void__card {
  max-width: 30rem;
  background: var(--sheet);
  border: 1px solid var(--trace);
  padding: 2rem 2rem 1.75rem;
  text-align: left;
}
.cp-void__no { font: 500 .75rem/1 var(--f-mono); letter-spacing: .14em; color: var(--trace); margin: 0 0 1rem; }
.cp-void h1 { margin: 0 0 .8rem; font: 700 1.7rem/1.35 var(--f-head); color: var(--ink); }
.cp-void p { margin: 0 0 1rem; }
.cp-void__go {
  display: inline-block; margin-top: .5rem;
  padding: .7rem 1.2rem;
  background: var(--trace); color: #fff; text-decoration: none; font-weight: 600;
  box-shadow: 4px 4px 0 var(--ink);
}
.cp-void__go:hover { color: #fff; background: var(--trace-deep); }

/* ---------- narrower sheets ---------- */

@media (width < 61.25rem) {
  .cp-main {
    grid-template-columns:
      [full-start] minmax(1rem, 1fr)
      [main-start] minmax(0, var(--measure))
      [main-end] minmax(1rem, 1fr)
      [full-end];
  }
  .cp-band { grid-row: 1 / 3; }
  .cp-doc > header[data-part="hero"] {
    grid-column: main-start / main-end;
    padding: 2.25rem 0 1.5rem;
  }
  .cp-plate {
    grid-row: 2;
    grid-column: main-start / main-end;
    margin: 1.4rem 0 2.25rem;
  }
  .cp-plate::after { display: none; }
  .cp-rail {
    grid-column: main-start / main-end;
    grid-row: 3;
    margin-top: 2rem;
  }
  .cp-tb { position: static; max-height: none; }
  .cp-rail.is-folded .cp-idx,
  .cp-rail.is-folded .cp-tb__foot { display: none; }
  .cp-doc > header + section { margin-top: 2.5rem; }
  .cp-foot__in { grid-template-columns: 1fr 1fr; }
  .cp-foot__id { grid-column: 1 / -1; }
}

@media (width < 40rem) {
  :root { --pin: 1.2rem; }
  body { font-size: 1rem; line-height: 1.8; }
  .cp-mark__name { font-size: 1.05rem; }
  .cp-nav a { font-size: .9rem; }
  .cp-doc > section { margin-top: 3.5rem; }
  .cp-doc h2 { grid-template-columns: 2.4rem 1fr; gap: .75rem; }
  .cp-doc h2::before { width: 2.4rem; height: 2.4rem; font-size: .7rem; }
  .cp-doc h2::after { width: 2.4rem; }
  .cp-doc table { display: block; overflow-x: auto; font-size: .88rem; }
  .cp-doc th, .cp-doc td { padding: .6rem .55rem; }
  .cp-doc table td:first-child { min-width: 5.5em; }
  figure[data-part="shot"] { padding: .5rem .5rem 0; }
  figure[data-part="shot"] figcaption { margin: .6rem -.5rem 0; padding: .6rem .6rem; flex-direction: column; gap: .4rem; }
  ol[data-part="legend"] > li { padding: .65rem .75rem; gap: .65rem; font-size: .92rem; }
  .cp-pin { font-size: .58rem; box-shadow: 0 0 0 1.5px #fff, 0 0 0 2.5px var(--trace), 0 2px 6px rgba(11, 26, 74, .3); }
  aside[data-part="cta"] { grid-template-columns: 1fr; }
  aside[data-part="cta"] > p:nth-of-type(1) { grid-row: auto; }
  aside[data-part="cta"] > p:nth-of-type(2) { padding: 1.2rem 1.15rem .2rem; }
  aside[data-part="cta"] > p:nth-of-type(3) { padding: .9rem 1.15rem 1.3rem; }
  aside[data-part="cta"] > p:nth-of-type(4) { padding: .9rem 1.15rem; }
  aside[data-part="cta"] a[data-cta] { width: calc(100% - 4px); justify-content: center; }
  #faq summary { grid-template-columns: 2.3rem 1fr 1.5rem; font-size: 1rem; }
  #faq details > :not(summary) { margin: 0 0 1.1rem 2.7rem; }
  .cp-foot__in { grid-template-columns: 1fr; }
  .cp-foot__cell { padding: .9rem 1rem; }
}
.cp-void + .cp-foot { margin-top: 0; }