/* ===== 品牌概况页 · page-about ===== */
.page-about {
  --about-rail-w: 210px;
  --about-gap: clamp(1.75rem, 4vw, 3.5rem);
  --about-sec-gap: clamp(2.75rem, 6vw, 5rem);
  position: relative;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + clamp(2rem, 5vw, 4rem)) 0 clamp(2rem, 4vw, 3.25rem);
  background-image:
    linear-gradient(180deg, rgba(34, 224, 214, 0.07), rgba(11, 16, 38, 0) 62%),
    repeating-linear-gradient(0deg, var(--line-soft) 0 1px, transparent 1px 96px),
    repeating-linear-gradient(90deg, var(--line-soft) 0 1px, transparent 1px 96px);
  background-color: var(--ink);
  border-bottom: 1px solid var(--line);
}
.page-about .about-hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
  align-items: end;
}
.page-about .about-hero-main { max-width: 74ch; }
.page-about .about-hero h1 {
  margin: 0.6rem 0 1rem;
  font-family: var(--font-display);
  font-size: var(--fs-display);
  font-weight: 800;
  line-height: 1.06;
  letter-spacing: -0.015em;
  color: var(--white);
}
.page-about .about-lead {
  margin: 0 0 1.9rem;
  max-width: 66ch;
  font-size: clamp(1rem, 1.15vw, 1.08rem);
  line-height: 1.85;
  color: var(--text);
}
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.1rem 1rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--line);
}
.page-about .about-stats .stat { display: flex; flex-direction: column; gap: 0.1rem; }
.page-about .about-stats .stat-value {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3.4vw, 2.15rem);
  font-weight: 600;
  line-height: 1;
  color: var(--gold);
}
.page-about .about-stats .stat-unit {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
  letter-spacing: 0.08em;
}
.page-about .about-stats .stat-label {
  font-size: 0.8rem;
  color: var(--text);
  letter-spacing: 0.02em;
}
.page-about .about-vert {
  writing-mode: vertical-rl;
  justify-self: start;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.3em;
  color: var(--muted);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-block: clamp(1.75rem, 4vw, 3rem) clamp(3rem, 6vw, 5rem);
}
.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: var(--about-sec-gap);
  min-width: 0;
}

/* ---------- 章节索引 ---------- */
.page-about .about-rail { min-width: 0; }
.page-about .rail-title {
  margin: 0 0 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.24em;
  color: var(--muted);
  text-transform: uppercase;
}
.page-about .about-rail-nav {
  display: flex;
  gap: 0.35rem;
  overflow-x: auto;
  padding-bottom: 0.25rem;
  scrollbar-width: thin;
}
.page-about .index-rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 0.45rem;
  flex: 0 0 auto;
  padding: 0.45rem 0.7rem;
  border-bottom: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background-color 180ms var(--ease);
}
.page-about .rail-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--line);
  transition: color 180ms var(--ease);
}
.page-about .index-rail-link:hover {
  color: var(--white);
  border-bottom-color: var(--magenta);
}
.page-about .index-rail-link:hover .rail-num { color: var(--magenta); }
.page-about .index-rail-link[aria-current="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
  background-color: var(--cyan-wash);
}
.page-about .index-rail-link[aria-current="true"] .rail-num { color: var(--cyan); }

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  position: relative;
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 1.25rem);
}
.page-about .section-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: baseline;
  gap: 0.25rem 0.85rem;
  margin-bottom: 1.35rem;
  padding-right: 0;
}
.page-about .section-index {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--cyan);
}
.page-about .section-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-section);
  font-weight: 700;
  line-height: 1.22;
  letter-spacing: -0.01em;
  color: var(--white);
}
.page-about .section-note {
  grid-column: 2;
  margin: 0.35rem 0 0;
  writing-mode: horizontal-tb;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.22em;
  color: var(--muted);
}
.page-about .about-prose { max-width: 68ch; }
.page-about .about-prose p {
  margin: 0 0 1rem;
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--text);
}
.page-about .about-prose p:last-child { margin-bottom: 0; }

/* ---------- 01 档案脉络 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 1.8rem 0 0;
  padding: 0 0 0 26px;
  border-left: 1px solid var(--line);
}
.page-about .about-timeline li {
  position: relative;
  padding: 0.85rem 0;
}
.page-about .about-timeline li + li { border-top: 1px solid var(--line-soft); }
.page-about .about-timeline li::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 1.28rem;
  width: 8px;
  height: 8px;
  background-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(34, 224, 214, 0.12);
}
.page-about .tl-title {
  margin: 0 0 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--white);
}
.page-about .tl-text {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--text);
  max-width: 62ch;
}

.page-about .about-media-wide {
  margin: 2rem 0 0;
  border: 1px solid var(--line);
  background-color: var(--panel-2);
  overflow: hidden;
}
.page-about .about-media-wide img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .media-cap {
  display: block;
  padding: 0.7rem 0.9rem;
  border-top: 1px solid var(--line);
  font-size: var(--fs-note);
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-accordion { margin-top: 1.9rem; border-top: 1px solid var(--line); }
.page-about .accordion-item { border-bottom: 1px solid var(--line-soft); }
.page-about .accordion-toggle {
  display: block;
  width: 100%;
  padding: 0.95rem 1.6rem 0.95rem 0;
  border: 0;
  background: transparent;
  text-align: left;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--white);
  cursor: pointer;
  position: relative;
  transition: color 180ms var(--ease);
}
.page-about .accordion-toggle::after {
  content: "+";
  position: absolute;
  right: 0.2rem;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  color: var(--cyan);
}
.page-about .accordion-toggle[aria-expanded="true"]::after { content: "–"; color: var(--magenta); }
.page-about .accordion-toggle:hover { color: var(--cyan); }
.page-about .accordion-panel { padding: 0 0 1rem; }
.page-about .accordion-panel p {
  margin: 0;
  max-width: 66ch;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--text);
}
.page-about .accordion-foot { margin-top: 0.9rem; }
.page-about .accordion-all {
  padding: 0.45rem 0.9rem;
  border: 1px solid var(--line);
  background: transparent;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--muted);
  cursor: pointer;
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}
.page-about .accordion-all:hover { color: var(--cyan); border-color: var(--cyan-line); }

/* ---------- 02 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.75rem;
}
.page-about .about-team-main { min-width: 0; }
.page-about .about-roster {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.1rem;
  margin: 1.6rem 0 0;
  padding: 1.2rem;
  border: 1px solid var(--line);
  background-color: var(--panel-2);
  box-shadow: var(--shadow-panel);
}
.page-about .roster-lead {
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
  padding-bottom: 0.9rem;
  border-bottom: 1px solid var(--line);
}
.page-about .roster-total {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4.5vw, 2.8rem);
  font-weight: 600;
  line-height: 1;
  color: var(--gold);
}
.page-about .roster-total-unit {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted);
}
.page-about .roster-total-label {
  margin-left: auto;
  font-size: 0.8rem;
  color: var(--text);
}
.page-about .roster-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.7rem 1rem;
}
.page-about .roster-list li { display: flex; align-items: baseline; gap: 0.5rem; }
.page-about .roster-num {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--cyan);
}
.page-about .roster-name { font-size: 0.85rem; color: var(--text); }

.page-about .about-steps {
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.4rem;
}
.page-about .about-step {
  position: relative;
  padding-top: 1.3rem;
  border-top: 1px solid var(--line);
  outline: none;
}
.page-about .about-step::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: 8px;
  height: 8px;
  background-color: var(--violet);
  transition: background-color 180ms var(--ease);
}
.page-about .about-step:hover::before,
.page-about .about-step:focus-within::before { background-color: var(--magenta); }
.page-about .step-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--muted);
}
.page-about .step-title {
  margin: 0.25rem 0 0.35rem;
  font-family: var(--font-display);
  font-size: 1.05rem;
  color: var(--white);
}
.page-about .step-text {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--text);
}
.page-about .step-detail {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 0.82rem;
  line-height: 1.75;
  color: var(--muted);
  transition: max-height 220ms var(--ease), opacity 220ms var(--ease), margin-top 220ms var(--ease);
}
.page-about .about-step:hover .step-detail,
.page-about .about-step:focus-within .step-detail {
  max-height: 12rem;
  opacity: 1;
  margin-top: 0.5rem;
}
.page-about .about-team-media {
  margin: 0;
  border: 1px solid var(--line);
  background-color: var(--panel-2);
  overflow: hidden;
}
.page-about .about-team-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 03 机型体系 ---------- */
.page-about .about-machine {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background-color: var(--line);
  border: 1px solid var(--line);
}
.page-about .machine-item {
  position: relative;
  padding: 1.1rem 1.1rem 1.25rem;
  background-color: var(--panel-2);
  transition: background-color 180ms var(--ease), box-shadow 180ms var(--ease);
}
.page-about .machine-item:hover {
  background-color: var(--panel);
  box-shadow: inset 0 0 0 1px var(--cyan-line);
}
.page-about .machine-name {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.05rem;
  color: var(--white);
}
.page-about .machine-text {
  margin: 0 0 0.8rem;
  font-size: 0.86rem;
  line-height: 1.72;
  color: var(--text);
}
.page-about .about-machine-media {
  margin: 1.6rem 0 0;
  border: 1px solid var(--line);
  overflow: hidden;
}
.page-about .about-machine-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-machine-foot {
  margin-top: 1.2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}
.page-about .about-machine-foot p {
  margin: 0;
  max-width: 66ch;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- 04 段位 ---------- */
.page-about .about-ladder {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 2px;
}
.page-about .ladder-step {
  padding: 0.7rem 0.2rem 0.8rem;
  border-top: 2px solid var(--cyan);
  background-image: linear-gradient(180deg, rgba(34, 224, 214, 0.16), rgba(11, 16, 38, 0));
  text-align: center;
}
.page-about .ladder-step:nth-child(3),
.page-about .ladder-step:nth-child(4) {
  border-top-color: var(--violet);
  background-image: linear-gradient(180deg, rgba(124, 92, 255, 0.16), rgba(11, 16, 38, 0));
}
.page-about .ladder-step:nth-child(5),
.page-about .ladder-step:nth-child(6),
.page-about .ladder-step:nth-child(7) {
  border-top-color: var(--gold);
  background-image: linear-gradient(180deg, rgba(242, 181, 68, 0.16), rgba(11, 16, 38, 0));
}
.page-about .ladder-score {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(0.72rem, 1.6vw, 0.92rem);
  font-weight: 600;
  color: var(--white);
}
.page-about .ladder-cap {
  display: block;
  margin-top: 0.2rem;
  font-size: 0.66rem;
  letter-spacing: 0.06em;
  color: var(--muted);
}
.page-about .about-rank-notes {
  margin-top: 1.8rem;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.2rem;
}
.page-about .rank-note {
  padding-top: 0.9rem;
  border-top: 1px solid var(--line);
}
.page-about .rank-note h3 {
  margin: 0 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--gold);
}
.page-about .rank-note p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--text);
}

/* ---------- 05 合作与认可 ---------- */
.page-about .about-index {
  list-style: none;
  margin: 1.7rem 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}
.page-about .about-index li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.25rem 1rem;
  padding: 0.85rem 0.65rem;
  border-bottom: 1px solid var(--line-soft);
  transition: background-color 180ms var(--ease), color 180ms var(--ease);
}
.page-about .about-index li:nth-child(odd) { background-color: rgba(20, 27, 58, 0.5); }
.page-about .about-index li:hover {
  background-color: var(--cyan);
}
.page-about .about-index li:hover .idx-name,
.page-about .about-index li:hover .idx-num,
.page-about .about-index li:hover .idx-detail { color: var(--ink); }
.page-about .about-index li:hover .dot { background-color: var(--ink); }
.page-about .idx-name {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--white);
  transition: color 180ms var(--ease);
}
.page-about .dot {
  width: 6px;
  height: 6px;
  flex: 0 0 6px;
  background-color: var(--gold);
  transition: background-color 180ms var(--ease);
}
.page-about .idx-detail {
  font-size: 0.84rem;
  line-height: 1.7;
  color: var(--muted);
  transition: color 180ms var(--ease);
}
.page-about .idx-num {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--gold);
  transition: color 180ms var(--ease);
}
.page-about .about-partner-foot {
  margin: 1.3rem 0 0;
  max-width: 66ch;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- 06 后续更新 ---------- */
.page-about .about-cta {
  margin-top: 1.9rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 600px) {
  .page-about .about-stats { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .page-about .about-machine { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-rank-notes { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .page-about .about-index li {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.6fr) auto;
    align-items: baseline;
  }
  .page-about .idx-num { text-align: right; }
  .page-about .about-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.6rem 1.4rem; }
}

@media (min-width: 900px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 2.5rem;
  }
  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
  }
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 1.5rem);
    align-self: start;
  }
  .page-about .about-rail-nav {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .index-rail-link {
    display: flex;
    width: 100%;
    padding: 0.55rem 0.6rem 0.55rem 0.85rem;
    border-bottom: 0;
    border-left: 1px solid var(--line);
    white-space: normal;
  }
  .page-about .index-rail-link:hover { border-left-color: var(--magenta); }
  .page-about .index-rail-link[aria-current="true"]:hover { border-left-color: var(--cyan); }

  .page-about .about-sec { padding-right: 2.4rem; }
  .page-about .section-head { padding-right: 2.6rem; }
  .page-about .section-note {
    position: absolute;
    top: 0.2rem;
    right: 0;
    grid-column: auto;
    margin: 0;
    writing-mode: vertical-rl;
    letter-spacing: 0.3em;
  }
  .page-about .about-sec--narrow { max-width: 82%; }
  .page-about .about-stats { grid-template-columns: repeat(5, minmax(0, 1fr)); }
  .page-about .about-machine { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .page-about .about-steps { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .page-about .about-team {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 0.85fr);
    gap: 2.2rem;
  }
  .page-about .about-team-media { align-self: start; }
}

@media (min-width: 1200px) {
  .page-about .about-rail { --about-rail-w: 230px; }
  .page-about .about-lead { font-size: 1.1rem; }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .index-rail-link,
  .page-about .rail-num,
  .page-about .accordion-toggle,
  .page-about .about-step::before,
  .page-about .step-detail,
  .page-about .machine-item,
  .page-about .about-index li,
  .page-about .dot,
  .page-about .idx-name,
  .page-about .idx-num,
  .page-about .idx-detail,
  .page-about .accordion-all {
    transition: none;
  }
  .page-about .about-step:hover .step-detail,
  .page-about .about-step:focus-within .step-detail { margin-top: 0.5rem; }
}
<<<END>>>