/* ===== 品牌介绍页 · page-about ===== */
.page-about {
  --about-rail-w: 232px;
  --about-line: rgba(127, 163, 156, .38);
  --about-body-text: rgba(239, 230, 210, .84);
  --about-muted: rgba(127, 163, 156, .95);
  display: block;
  background: var(--sq-night);
  color: var(--sq-paper);
  font-family: var(--sq-font-body);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 3.4vw, 34px) 0 clamp(32px, 5.4vw, 68px);
  background:
    radial-gradient(120% 100% at 88% -16%, rgba(53, 224, 208, .18), rgba(53, 224, 208, 0) 58%),
    linear-gradient(180deg, var(--sq-ink) 0%, var(--sq-night) 100%);
  border-bottom: var(--sq-edge) solid var(--sq-carbon);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -90px;
  bottom: -140px;
  width: 300px;
  height: 300px;
  border: 3px solid rgba(232, 163, 61, .2);
  transform: rotate(16deg);
  pointer-events: none;
}

.page-about .about-hero .sq-breadcrumb {
  position: relative;
  z-index: 1;
  margin: 0 0 clamp(18px, 3vw, 32px);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--about-muted);
}

.page-about .about-hero .sq-breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-hero .sq-breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: rgba(127, 163, 156, .55);
}

.page-about .about-hero .sq-breadcrumb a {
  color: var(--sq-cyan);
  text-decoration: none;
}

.page-about .about-hero .sq-breadcrumb a:hover {
  text-decoration: underline;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  align-items: end;
}

.page-about .about-hero .sq-eyebrow {
  color: var(--sq-amber);
  font-family: var(--sq-font-mono);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  margin: 0;
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--sq-font-head);
  font-size: clamp(28px, 6.4vw, 56px);
  line-height: 1.14;
  letter-spacing: .04em;
  color: var(--sq-paper-white);
  text-wrap: balance;
}

.page-about .about-hero .sq-lede {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.8;
  color: var(--about-body-text);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-fact {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 16px;
  background: rgba(14, 42, 38, .78);
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
  transition: box-shadow .18s ease, transform .18s ease;
}

.page-about .about-fact:hover {
  box-shadow: var(--sq-shadow-press);
  transform: translate(2px, 2px);
}

.page-about .about-fact__num {
  font-family: var(--sq-font-mono);
  font-size: clamp(24px, 4vw, 30px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--sq-amber);
}

.page-about .about-fact__label {
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--about-muted);
}

/* ---------- 主体双栏 ---------- */
.page-about .about-body {
  background: linear-gradient(180deg, var(--sq-night) 0%, var(--sq-ink) 100%);
  padding: clamp(26px, 4vw, 56px) 0 clamp(40px, 6vw, 88px);
}

.page-about .about-body__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 52px);
  align-items: start;
}

/* 左侧刻度轴 */
.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
  font-family: var(--sq-font-mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--about-muted);
  text-transform: uppercase;
}

.page-about .about-rail__scale {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__scale > .sq-scale__item {
  flex: 0 0 auto;
  position: relative;
}

.page-about .about-rail__link {
  display: grid;
  grid-template-columns: auto auto;
  align-items: baseline;
  gap: 6px 10px;
  padding: 10px 14px;
  border: 2px solid rgba(127, 163, 156, .3);
  background: rgba(14, 42, 38, .55);
  color: var(--about-muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color .18s ease, border-color .18s ease, background-color .18s ease;
}

.page-about .about-rail__link:hover {
  color: var(--sq-paper-white);
  border-color: var(--sq-cyan);
}

.page-about .about-rail__scale .sq-scale__num {
  font-family: var(--sq-font-mono);
  font-size: 15px;
  letter-spacing: .02em;
  color: var(--sq-amber);
}

.page-about .about-rail__scale .sq-scale__label {
  font-family: var(--sq-font-head);
  font-size: 14px;
  letter-spacing: .06em;
}

.page-about .about-rail__hint {
  grid-column: 1 / -1;
  font-family: var(--sq-font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: rgba(127, 163, 156, .8);
}

.page-about .about-rail__scale .sq-scale__item[data-active] .about-rail__link {
  color: var(--sq-paper-white);
  border-color: var(--sq-cyan);
  background: rgba(53, 224, 208, .12);
}

.page-about .about-rail__scale .sq-scale__item[data-done] .about-rail__link {
  border-color: rgba(232, 163, 61, .55);
}

/* 右侧叙述流 */
.page-about .about-flow {
  min-width: 0;
  display: grid;
  gap: clamp(34px, 5.6vw, 78px);
}

.page-about .about-chapter {
  min-width: 0;
  scroll-margin-top: 112px;
  border-top: var(--sq-edge) solid rgba(127, 163, 156, .26);
  padding-top: clamp(18px, 3vw, 30px);
}

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.page-about .about-chapter__num {
  font-family: var(--sq-font-mono);
  font-size: clamp(30px, 5.2vw, 50px);
  line-height: .9;
  letter-spacing: -.03em;
  color: var(--sq-amber);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--sq-font-head);
  font-size: clamp(21px, 3.2vw, 32px);
  line-height: 1.3;
  letter-spacing: .05em;
  color: var(--sq-paper-white);
}

.page-about .about-chapter p {
  margin: 0 0 14px;
  max-width: 40em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-body-text);
}

/* 图容器 */
.page-about .about-figure {
  margin: 24px 0;
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
  background: var(--sq-ink);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure .sq-figure__cap {
  font-family: var(--sq-font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--sq-amber);
  background: rgba(11, 15, 18, .82);
  padding: 6px 10px;
}

/* 里程碑 */
.page-about .about-miles {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 22px;
  border-left: 2px dashed var(--about-line);
  display: grid;
  gap: 18px;
}

.page-about .about-mile {
  position: relative;
}

.page-about .about-mile::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 6px;
  width: 11px;
  height: 11px;
  background: var(--sq-amber);
  border: 2px solid var(--sq-night);
}

.page-about .about-mile__year {
  display: block;
  font-family: var(--sq-font-mono);
  font-size: 18px;
  letter-spacing: .06em;
  color: var(--sq-cyan);
}

.page-about .about-mile__text {
  margin: 6px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--about-body-text);
}

/* 短引述 */
.page-about .about-quote {
  margin: 26px 0 0;
  padding: clamp(18px, 3vw, 28px);
  background: var(--sq-paper);
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
  border-left: 10px solid var(--sq-red);
}

.page-about .about-chapter .about-quote p {
  margin: 0;
  max-width: 28em;
  font-family: var(--sq-font-head);
  font-size: clamp(18px, 2.2vw, 23px);
  line-height: 1.55;
  letter-spacing: .02em;
  color: var(--sq-ink);
}

/* 表格 */
.page-about .about-table-wrap {
  margin: 24px 0;
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
  background: rgba(11, 15, 18, .55);
  overflow-x: auto;
}

.page-about .about-table {
  width: 100%;
  min-width: 480px;
  border-collapse: collapse;
}

.page-about .about-table__cap {
  caption-side: top;
  text-align: left;
  padding: 14px 16px 8px;
  font-family: var(--sq-font-head);
  font-size: 13px;
  letter-spacing: .12em;
  color: var(--sq-sage);
}

.page-about .about-table th,
.page-about .about-table td {
  padding: 12px 16px;
  text-align: left;
  font-size: 15px;
  line-height: 1.6;
  border-bottom: 1px solid rgba(127, 163, 156, .26);
  color: var(--about-body-text);
}

.page-about .about-table thead th {
  position: sticky;
  top: 0;
  background: var(--sq-ink);
  font-family: var(--sq-font-head);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--sq-paper-white);
  border-bottom: 2px solid var(--sq-carbon);
}

.page-about .about-table tbody th {
  font-family: var(--sq-font-mono);
  font-weight: 500;
  letter-spacing: .04em;
  color: var(--sq-amber);
  white-space: nowrap;
}

.page-about .about-table .sq-num-cell {
  font-family: var(--sq-font-mono);
  color: var(--sq-cyan);
}

.page-about .about-table tbody tr:last-child th,
.page-about .about-table tbody tr:last-child td {
  border-bottom: 0;
}

/* 校对步骤 */
.page-about .about-steps {
  list-style: none;
  margin: 26px 0 24px;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-step {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 18px;
  background: rgba(14, 42, 38, .6);
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
}

.page-about .about-step__num {
  font-family: var(--sq-font-mono);
  font-size: 22px;
  line-height: 1.1;
  color: var(--sq-cyan);
}

.page-about .about-step__body h3 {
  margin: 0 0 6px;
  font-family: var(--sq-font-head);
  font-size: 17px;
  letter-spacing: .06em;
  color: var(--sq-paper-white);
}

.page-about .about-step__body p {
  margin: 0;
  max-width: 36em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--about-body-text);
}

/* 团队分工 */
.page-about .about-roles {
  margin-top: 22px;
  display: grid;
  gap: 12px;
}

.page-about .about-role {
  border: var(--sq-edge) solid var(--sq-carbon);
  background: rgba(11, 22, 38, .72);
  box-shadow: var(--sq-shadow);
}

.page-about .about-role summary {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px 14px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .about-role summary::-webkit-details-marker {
  display: none;
}

.page-about .about-role summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--sq-font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--sq-cyan);
}

.page-about .about-role[open] summary::after {
  content: "–";
}

.page-about .about-role[open] summary {
  border-bottom: 2px solid rgba(127, 163, 156, .3);
}

.page-about .about-role__num {
  font-family: var(--sq-font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--sq-amber);
}

.page-about .about-role__name {
  font-family: var(--sq-font-head);
  font-size: 18px;
  letter-spacing: .06em;
  color: var(--sq-paper-white);
}

.page-about .about-role__hint {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--about-muted);
}

.page-about .about-role__body {
  padding: 16px 18px 18px;
}

.page-about .about-role__body p {
  margin: 0;
  max-width: 36em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--about-body-text);
}

/* 区域与备案信息板 */
.page-about .about-region {
  margin: 24px 0;
  background: var(--sq-paper);
  border: var(--sq-edge) solid var(--sq-carbon);
  box-shadow: var(--sq-shadow);
  padding: 4px 0;
}

.page-about .about-region__row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px 18px;
  padding: 13px 18px;
  border-bottom: 1px dashed rgba(14, 42, 38, .3);
}

.page-about .about-region__row:last-child {
  border-bottom: 0;
}

.page-about .about-region__label {
  font-family: var(--sq-font-head);
  font-size: 13px;
  letter-spacing: .14em;
  color: #4a5f58;
}

.page-about .about-region__value {
  font-family: var(--sq-font-mono);
  font-size: 16px;
  letter-spacing: .02em;
  color: var(--sq-ink);
}

/* 内联按钮组 */
.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

/* 行动区 */
.page-about .about-cta {
  margin: 0;
  padding: clamp(22px, 3.6vw, 38px);
  border: var(--sq-edge) solid var(--sq-cyan);
  background:
    linear-gradient(135deg, rgba(53, 224, 208, .14) 0%, rgba(11, 15, 18, .72) 62%),
    var(--sq-night);
  box-shadow: var(--sq-shadow);
}

.page-about .about-cta__title {
  margin: 0 0 12px;
  font-family: var(--sq-font-head);
  font-size: clamp(21px, 3vw, 30px);
  line-height: 1.3;
  letter-spacing: .05em;
  color: var(--sq-paper-white);
}

.page-about .about-cta__text {
  margin: 0 0 20px;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-body-text);
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) and (max-width: 899px) {
  .page-about .about-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-fact {
    flex-direction: column;
    gap: 6px;
  }

  .page-about .about-step {
    grid-template-columns: 56px minmax(0, 1fr);
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  }
}

@media (min-width: 1000px) {
  .page-about .about-body__inner {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(30px, 4vw, 60px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__scale {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 4px 0 4px 20px;
    position: relative;
  }

  .page-about .about-rail__scale::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 12px;
    bottom: 12px;
    width: 2px;
    background: var(--about-line);
  }

  .page-about .about-rail__link {
    grid-template-columns: auto minmax(0, 1fr);
    grid-template-areas:
      "num label"
      "hint hint";
    white-space: normal;
    border-color: transparent;
    background: transparent;
    padding: 11px 8px 13px 0;
    column-gap: 10px;
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -19px;
    top: 17px;
    width: 10px;
    height: 10px;
    background: var(--sq-night);
    border: 2px solid var(--sq-sage);
    transform: rotate(45deg);
    transition: background-color .18s ease, border-color .18s ease, box-shadow .18s ease;
  }

  .page-about .about-rail__link:hover {
    border-color: transparent;
  }

  .page-about .about-rail__scale .sq-scale__num {
    grid-area: num;
  }

  .page-about .about-rail__scale .sq-scale__label {
    grid-area: label;
  }

  .page-about .about-rail__hint {
    grid-area: hint;
    margin-top: 3px;
    padding-left: 2px;
  }

  .page-about .about-rail__scale .sq-scale__item[data-active] .about-rail__link {
    background: transparent;
    border-color: transparent;
  }

  .page-about .about-rail__scale .sq-scale__item[data-active] .about-rail__link::before {
    background: var(--sq-cyan);
    border-color: var(--sq-cyan);
    box-shadow: 0 0 0 5px rgba(53, 224, 208, .16);
  }

  .page-about .about-rail__scale .sq-scale__item[data-done] .about-rail__link {
    border-color: transparent;
  }

  .page-about .about-rail__scale .sq-scale__item[data-done] .about-rail__link::before {
    background: var(--sq-amber);
    border-color: var(--sq-amber);
  }

  .page-about .about-quote {
    margin-left: clamp(0px, 3vw, 46px);
    margin-right: clamp(0px, 6vw, 90px);
  }

  .page-about .about-step {
    grid-template-columns: 60px minmax(0, 1fr);
    padding: 18px 22px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-step:nth-child(even) {
    margin-left: 34px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-fact,
  .page-about .about-rail__link,
  .page-about .about-rail__link::before {
    transition: none;
  }

  .page-about .about-fact:hover {
    transform: none;
  }
}