.page-about {
  --about-pad-x: 20px;
  --about-pad-y: 26px;
  --about-ink-line: rgba(26, 26, 31, .16);
  --about-ink-soft: rgba(26, 26, 31, .55);
  display: block;
  background: var(--ink);
  color: var(--fg);
}

@media (min-width: 760px) {
  .page-about {
    --about-pad-x: 48px;
    --about-pad-y: 52px;
  }
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + 44px) 0 46px;
  background:
    radial-gradient(120% 130% at 8% 0%, rgba(53, 230, 210, .13), transparent 58%),
    radial-gradient(90% 110% at 96% 8%, rgba(226, 62, 140, .10), transparent 60%),
    linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 100%);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(124, 138, 166, .16) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(124, 138, 166, .16) 1px, transparent 1px);
  background-size: 80px 80px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, .85), transparent 90%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, .85), transparent 90%);
  pointer-events: none;
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 30px;
}

.page-about .about-hero__kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 0 0 22px;
  max-width: 20ch;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(30px, 6.4vw, 58px);
  line-height: 1.16;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 64ch;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.9;
  color: var(--fg-soft);
}

.page-about .about-stats {
  list-style: none;
  margin: 40px 0 0;
  padding: 22px 0 0;
  border-top: 1px solid var(--line-strong);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 18px;
}

@media (min-width: 820px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-stats__item {
  border-left: 2px solid var(--line-strong);
  padding-left: 14px;
}

.page-about .about-stats__value {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(30px, 5vw, 44px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-stats__value--cyan {
  color: var(--cyan);
}

.page-about .about-stats__value--orange {
  color: var(--orange);
}

.page-about .about-stats__label {
  display: block;
  margin-top: 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .04em;
  color: var(--fg-mute);
}

/* ---------- 主体骨架 ---------- */

.page-about .about-body {
  padding: 46px 0 84px;
}

.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
}

@media (min-width: 1080px) {
  .page-about .about-body__grid {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 44px;
    align-items: start;
  }
}

/* ---------- 左侧章节索引 ---------- */

.page-about .about-index {
  padding-left: 14px;
  border-left: 2px solid var(--line);
}

.page-about .about-index__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--fg-mute);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-index__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 7px 4px 7px 10px;
  border-left: 2px solid transparent;
  color: var(--fg-mute);
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.5;
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--grid);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--paper);
  border-left-color: var(--cyan);
}

.page-about .about-index__link:hover .about-index__num,
.page-about .about-index__link:focus-visible .about-index__num {
  color: var(--cyan);
}

@media (min-width: 1080px) {
  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    padding-left: 0;
    border-left: 0;
  }

  .page-about .about-index__list {
    gap: 0;
  }

  .page-about .about-index__link {
    border-left: 2px solid var(--line);
    padding-left: 12px;
  }
}

/* ---------- 纸面 ---------- */

.page-about .about-paper {
  position: relative;
  background: var(--paper);
  color: var(--paper-ink);
  padding: var(--about-pad-y) var(--about-pad-x);
  border: 1px solid var(--paper-2);
  box-shadow:
    0 22px 0 -14px rgba(0, 0, 0, .5),
    0 0 0 1px rgba(255, 255, 255, .05);
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 0 0 34px;
}

.page-about .about-figure__frame {
  position: relative;
  border: 1px solid rgba(26, 26, 31, .28);
  padding: 6px;
  background: var(--paper-2);
}

.page-about .about-figure__frame::after {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px dashed rgba(26, 26, 31, .22);
  pointer-events: none;
}

.page-about .about-figure__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--ink-2);
}

.page-about .about-figure--inline .about-figure__img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure__cap {
  margin: 12px 0 0;
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--about-ink-soft);
}

.page-about .about-figure--lead {
  margin-bottom: 40px;
}

.page-about .about-figure--inline {
  margin: 26px 0;
}

/* ---------- 章节 ---------- */

.page-about .about-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px 36px;
}

.page-about .about-section + .about-section {
  margin-top: 52px;
  padding-top: 44px;
  border-top: 1px solid var(--about-ink-line);
}

@media (min-width: 960px) {
  .page-about .about-section {
    grid-template-columns: minmax(0, 1fr) 206px;
  }
}

.page-about .about-section__head {
  grid-column: 1 / -1;
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--paper-ink);
}

.page-about .about-section__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--magenta);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(21px, 3.2vw, 27px);
  line-height: 1.4;
  letter-spacing: -.005em;
  color: var(--paper-ink);
}

.page-about .about-section__main {
  min-width: 0;
}

.page-about .about-section__main p {
  margin: 0 0 18px;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.92;
  color: var(--paper-ink);
}

@media (min-width: 760px) {
  .page-about .about-section__main p {
    font-size: 17px;
  }
}

.page-about .about-section__main p:last-child {
  margin-bottom: 0;
}

.page-about .about-inline-link {
  color: var(--paper-ink);
  text-decoration: none;
  border-bottom: 2px solid var(--orange);
  padding-bottom: 1px;
}

.page-about .about-inline-link:hover {
  border-bottom-color: var(--magenta);
}

.page-about .about-section__aside {
  min-width: 0;
  padding-top: 10px;
  border-top: 1px solid var(--paper-ink);
}

.page-about .about-margin {
  padding: 9px 0;
  border-bottom: 1px dashed var(--about-ink-line);
}

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

.page-about .about-margin__key {
  display: block;
  margin-bottom: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--about-ink-soft);
}

.page-about .about-margin__value {
  display: block;
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1.6;
  color: var(--paper-ink);
}

/* ---------- 三层流程 ---------- */

.page-about .about-steps {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 26px;
  border-left: 1px solid var(--about-ink-line);
  display: grid;
  gap: 26px;
}

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

.page-about .about-steps__item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: .5em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--magenta);
}

.page-about .about-steps__title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.5;
  color: var(--paper-ink);
}

.page-about .about-steps__num {
  display: inline-block;
  margin-right: 10px;
  padding: 1px 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: .08em;
  color: var(--paper);
  background: var(--paper-ink);
  vertical-align: 2px;
}

.page-about .about-steps__item p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.88;
  color: var(--paper-ink);
}

/* ---------- 版本时间轴（深色色带） ---------- */

.page-about .about-band {
  margin: 52px calc(-1 * var(--about-pad-x)) 52px;
  padding: 40px var(--about-pad-x) 46px;
  background:
    linear-gradient(180deg, rgba(22, 34, 74, .96) 0%, rgba(11, 18, 32, 1) 100%);
  border-top: 3px solid var(--cyan);
  border-bottom: 1px solid var(--line);
  color: var(--fg);
}

.page-about .about-band__head {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line-strong);
}

.page-about .about-band__num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--cyan);
}

.page-about .about-band__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(22px, 3.4vw, 29px);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-band__lead {
  margin: 0;
  max-width: 62ch;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--fg-soft);
}

.page-about .about-figure--band {
  margin: 28px 0 6px;
}

.page-about .about-figure--band .about-figure__frame {
  border-color: var(--line-strong);
  background: var(--ink-3);
}

.page-about .about-figure--band .about-figure__frame::after {
  border-color: rgba(124, 138, 166, .34);
}

.page-about .about-figure--band .about-figure__img {
  aspect-ratio: 2 / 1;
}

.page-about .about-versions {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 26px;
}

@media (min-width: 900px) {
  .page-about .about-versions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
  }
}

.page-about .about-versions__item {
  position: relative;
  padding-top: 20px;
  border-top: 2px solid var(--line-strong);
}

@media (min-width: 900px) {
  .page-about .about-versions__item {
    padding: 26px 22px 0 0;
  }

  .page-about .about-versions__item::before {
    content: "";
    position: absolute;
    left: 0;
    top: -6px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--grid);
  }

  .page-about .about-versions__item:nth-child(1)::before { background: var(--grid); }
  .page-about .about-versions__item:nth-child(2)::before { background: var(--orange); }
  .page-about .about-versions__item:nth-child(3)::before { background: var(--cyan); }
  .page-about .about-versions__item:nth-child(4)::before { background: var(--magenta); }
}

.page-about .about-versions__ver {
  display: block;
  margin-bottom: 9px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 21px;
  letter-spacing: .03em;
  color: var(--grid);
}

.page-about .about-versions__item:nth-child(2) .about-versions__ver { color: var(--orange); }
.page-about .about-versions__item:nth-child(3) .about-versions__ver { color: var(--cyan); }
.page-about .about-versions__item:nth-child(4) .about-versions__ver { color: var(--magenta); }

.page-about .about-versions__label {
  margin: 0 0 12px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.55;
  color: var(--paper);
}

.page-about .about-versions__fields {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-versions__fields li {
  position: relative;
  padding-left: 14px;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.75;
  color: var(--fg-soft);
}

.page-about .about-versions__fields li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 6px;
  height: 1px;
  background: var(--grid);
}

/* ---------- 表格 ---------- */

.page-about .about-table-wrap {
  margin: 24px 0 22px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
}

.page-about .about-table th {
  padding: 0 14px 10px 0;
  text-align: left;
  vertical-align: bottom;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: .1em;
  color: var(--about-ink-soft);
  border-bottom: 2px solid var(--paper-ink);
}

.page-about .about-table td {
  padding: 14px 14px 14px 0;
  vertical-align: top;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper-ink);
  border-bottom: 1px solid var(--about-ink-line);
}

.page-about .about-table .is-num {
  font-family: var(--font-mono);
  font-size: 13px;
  white-space: nowrap;
}

.page-about .about-league {
  display: inline-block;
  padding: 2px 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--paper);
  white-space: nowrap;
}

.page-about .about-league--a { background: #0E7C72; }
.page-about .about-league--b { background: #B85A1E; }
.page-about .about-league--c { background: #A82663; }
.page-about .about-league--d { background: #5F7A17; }

/* ---------- 团队名单 ---------- */

.page-about .about-roster {
  list-style: none;
  margin: 24px 0 22px;
  padding: 0;
  display: grid;
  gap: 20px;
}

@media (min-width: 720px) {
  .page-about .about-roster {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 32px;
  }
}

.page-about .about-roster__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 16px;
  padding-left: 16px;
  border-left: 3px solid var(--paper-ink);
}

.page-about .about-roster__num {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 38px;
  line-height: .92;
  letter-spacing: -.03em;
  color: var(--paper-ink);
}

.page-about .about-roster__body {
  min-width: 0;
}

.page-about .about-roster__role {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--paper-ink);
}

.page-about .about-roster__desc {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.82;
  color: var(--about-ink-soft);
}

/* ---------- 边界清单 ---------- */

.page-about .about-limits {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 15px;
}

.page-about .about-limits li {
  position: relative;
  padding-left: 30px;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.86;
  color: var(--paper-ink);
}

.page-about .about-limits li::before {
  content: "—";
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--font-mono);
  color: var(--magenta);
}

/* ---------- 注释 ---------- */

.page-about .about-section--notes .about-section__head {
  border-bottom-width: 1px;
}

.page-about .about-notes {
  margin: 0;
  padding-left: 22px;
  display: grid;
  gap: 12px;
}

.page-about .about-notes li {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

.page-about .about-notes__back {
  margin-left: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--paper-ink);
  text-decoration: none;
  border-bottom: 1px solid var(--about-ink-line);
}

/* ---------- 页尾导航 ---------- */

.page-about .about-next {
  margin-top: 52px;
  padding-top: 30px;
  border-top: 2px solid var(--paper-ink);
}

.page-about .about-next__lead {
  margin: 0 0 20px;
  max-width: 66ch;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.9;
  color: var(--paper-ink);
}

.page-about .about-next__links {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
}

.page-about .about-next__link {
  display: inline-block;
  padding: 8px 16px;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.4;
  color: var(--paper-ink);
  text-decoration: none;
  border: 1px solid var(--paper-ink);
  background: transparent;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  background: var(--paper-ink);
  color: var(--paper);
}

.page-about .about-next__link:first-child {
  background: var(--paper-ink);
  color: var(--paper);
}

.page-about .about-next__link:first-child:hover,
.page-about .about-next__link:first-child:focus-visible {
  background: #000;
}

/* ---------- 窄屏收敛 ---------- */

@media (max-width: 560px) {
  .page-about .about-hero__title {
    max-width: none;
  }

  .page-about .about-stats__item {
    border-left-width: 2px;
    padding-left: 12px;
  }

  .page-about .about-roster__num {
    font-size: 30px;
  }

  .page-about .about-versions__ver {
    font-size: 18px;
  }

  .page-about .about-table {
    min-width: 520px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .about-next__link {
    transition: none;
  }
}
</style>