.page-about {
  display: block;
  background: var(--ink);
  color: var(--chalk);
  --about-accent-line: rgba(242, 194, 0, .55);
  --about-paper-line: rgba(184, 134, 11, .28);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: 28px;
  position: relative;
  background:
    linear-gradient(180deg, rgba(18, 58, 46, .55) 0%, rgba(14, 27, 42, 0) 62%);
}

.page-about .about-hero .wrap {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about .about-hero h1 {
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(28px, 6vw, 54px);
  line-height: 1.12;
  letter-spacing: -.02em;
  margin: 0;
  max-width: 22ch;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 66ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.78;
  color: rgba(244, 247, 245, .82);
  border-left: 3px solid var(--yellow);
  padding-left: 14px;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin: 14px 0 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-stat {
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

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

.page-about .about-stat__label {
  font-family: var(--font-sans);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--slate);
  font-weight: 700;
}

.page-about .about-stat__value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(34px, 7vw, 62px);
  line-height: 1;
  color: var(--chalk);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat__value span {
  font-size: .36em;
  margin-left: 6px;
  color: var(--cyan);
  letter-spacing: .04em;
}

.page-about .about-banner {
  margin: 22px 0 0;
  position: relative;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--turf-deep);
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  aspect-ratio: 16 / 7;
  object-fit: cover;
  filter: saturate(.86) contrast(1.04);
}

.page-about .about-banner__cap {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
  padding: 8px var(--pad) 10px;
  border-top: 1px solid var(--line);
  letter-spacing: .04em;
}

/* ---------- 布局 ---------- */
.page-about .about-layout {
  display: block;
  padding-top: 34px;
  padding-bottom: 60px;
}

.page-about .about-toc {
  border: 1px solid var(--line);
  background: var(--turf-deep);
  padding: 16px 18px;
  margin-bottom: 34px;
}

.page-about .about-toc__title {
  margin: 0 0 12px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--yellow);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
}

.page-about .about-toc__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 7px 6px;
  color: rgba(244, 247, 245, .84);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.5;
  border-left: 2px solid transparent;
  transition: border-color var(--dur) ease, background var(--dur) ease, color var(--dur) ease;
}

.page-about .about-toc__list a .num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
  font-variant-numeric: tabular-nums;
}

.page-about .about-toc__list a:hover {
  border-left-color: var(--cyan);
  background: rgba(53, 224, 200, .07);
  color: var(--chalk);
}

.page-about .about-toc__list a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 1px;
}

.page-about .about-toc__src {
  margin: 14px 0 0;
  display: block;
}

.page-about .about-main {
  display: flex;
  flex-direction: column;
  gap: 0;
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: 30px 0 34px;
  border-top: 1px solid var(--line);
}

.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-sec[data-anchor]:target {
  border-left: 3px solid var(--yellow);
  padding-left: 14px;
}

.page-about .about-sec .section__head {
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 10px;
  margin-bottom: 20px;
}

.page-about .about-sec .section__title {
  font-size: clamp(19px, 3.6vw, 27px);
  line-height: 1.25;
  letter-spacing: -.01em;
}

.page-about .about-sec .prose p {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.82;
  color: rgba(244, 247, 245, .86);
  max-width: 68ch;
}

.page-about .about-sec .src {
  display: block;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.7;
  color: var(--slate);
  letter-spacing: .01em;
}

.page-about .about-sec .src a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 200, .4);
  transition: border-color var(--dur) ease, color var(--dur) ease;
}

.page-about .about-sec .src a:hover {
  border-bottom-color: var(--cyan);
  color: var(--chalk);
}

/* ---------- 四条主线索引 ---------- */
.page-about .about-lines {
  list-style: none;
  margin: 8px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-line {
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 12px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
  border-left: 3px solid transparent;
  padding-left: 12px;
  transition: background var(--dur) ease, border-left-color var(--dur) ease;
}

.page-about .about-line:hover {
  background: rgba(18, 58, 46, .5);
  border-left-color: var(--cyan);
}

.page-about .about-line__no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 17px;
  color: var(--slate);
  font-variant-numeric: tabular-nums;
  padding-top: 2px;
}

.page-about .about-line--ruling .about-line__no { color: var(--yellow); }
.page-about .about-line--report .about-line__no { color: var(--turf); background: var(--cyan); text-align: center; }
.page-about .about-line--window .about-line__no { color: var(--cyan); }
.page-about .about-line--odds .about-line__no { color: var(--slate); }

.page-about .about-line__name {
  margin: 0 0 6px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 16.5px;
  letter-spacing: -.01em;
  color: var(--chalk);
}

.page-about .about-line__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(244, 247, 245, .78);
  max-width: 62ch;
}

/* ---------- 三步流程（CSS 计数器） ---------- */
.page-about .about-steps {
  counter-reset: step;
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  border: 1px solid var(--line);
  background: rgba(10, 36, 28, .55);
}

.page-about .about-step {
  counter-increment: step;
  padding: 18px 18px 18px 18px;
  border-bottom: 1px solid var(--line);
  position: relative;
  transition: background var(--dur) ease;
}

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

.page-about .about-step:hover {
  background: rgba(53, 224, 200, .06);
}

.page-about .about-step::before {
  content: counter(step, decimal-leading-zero);
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--yellow);
  margin-bottom: 8px;
  font-variant-numeric: tabular-nums;
}

.page-about .about-step__name {
  margin: 0 0 6px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 15.5px;
  color: var(--chalk);
}

.page-about .about-step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(244, 247, 245, .78);
  max-width: 60ch;
}

.page-about .about-steps--compact {
  background: transparent;
  border-color: var(--line);
}

/* ---------- 图片组 ---------- */
.page-about .about-figure {
  margin: 24px 0 0;
  border: 1px solid var(--line);
  background: var(--turf-deep);
}

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

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure--side img {
  aspect-ratio: 8 / 5;
}

.page-about .about-figure__cap {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
  padding: 9px 14px;
  border-top: 1px solid var(--line);
  letter-spacing: .03em;
}

/* ---------- 记录板米区 ---------- */
.page-about .board {
  margin-top: 26px;
  background: var(--paper);
  color: var(--amber);
  border: 1px solid rgba(184, 134, 11, .4);
}

.page-about .board__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--about-paper-line);
}

.page-about .board__title {
  margin: 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 15px;
  letter-spacing: .01em;
  color: #6b4f06;
}

.page-about .board .tag--muted {
  background: rgba(184, 134, 11, .14);
  color: #7a5b08;
  border-color: rgba(184, 134, 11, .4);
}

.page-about .board__item {
  border-bottom: 1px solid var(--about-paper-line);
}

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

.page-about .board__item summary {
  cursor: pointer;
  list-style: none;
  padding: 15px 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 15px;
  line-height: 1.6;
  color: #5c4305;
  transition: background var(--dur) ease, color var(--dur) ease;
}

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

.page-about .board__item summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--amber);
}

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

.page-about .board__item summary:hover {
  background: rgba(184, 134, 11, .1);
}

.page-about .board__item summary:focus-visible {
  outline: 2px solid #6b4f06;
  outline-offset: -2px;
}

.page-about .board__item summary .num {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: #8a6708;
  font-variant-numeric: tabular-nums;
}

.page-about .board__item p {
  margin: 0 0 12px;
  padding: 0 16px;
  font-size: 14.5px;
  line-height: 1.8;
  color: #4a3803;
  max-width: 64ch;
}

.page-about .board__item .src {
  margin-bottom: 16px;
  color: #7a5b08;
  font-family: var(--font-mono);
  font-size: 11px;
}

/* ---------- 双栏分列 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin-top: 20px;
  border-top: 1px solid var(--line);
}

.page-about .about-split__col {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-split__name {
  margin: 0 0 10px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 15.5px;
  color: var(--cyan);
  letter-spacing: .01em;
}

.page-about .about-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-list li {
  position: relative;
  padding: 6px 0 6px 18px;
  font-size: 14.5px;
  line-height: 1.72;
  color: rgba(244, 247, 245, .8);
  max-width: 58ch;
}

.page-about .about-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 15px;
  width: 8px;
  height: 1px;
  background: var(--yellow);
}

/* ---------- 战报与转会对照 ---------- */
.page-about .about-pairs {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin-top: 20px;
}

.page-about .about-pair {
  padding: 20px 0 4px;
  border-top: 1px solid var(--line);
}

.page-about .about-pair__name {
  margin: 0 0 8px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 17px;
  color: var(--chalk);
}

.page-about .about-pair__lead {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.8;
  color: var(--yellow);
  max-width: 46ch;
  padding-left: 12px;
  border-left: 2px solid var(--about-accent-line);
}

/* ---------- 赔率指标 ---------- */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin: 22px 0 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(10, 36, 28, .5);
}

.page-about .about-metric {
  padding: 16px 18px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  transition: background var(--dur) ease;
}

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

.page-about .about-metric:hover {
  background: rgba(53, 224, 200, .06);
}

.page-about .about-metric dt {
  font-size: 13.5px;
  color: var(--slate);
  letter-spacing: .02em;
}

.page-about .about-metric dd {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(24px, 5vw, 38px);
  line-height: 1;
  color: var(--chalk);
  font-variant-numeric: tabular-nums;
}

.page-about .about-metric dd span {
  font-size: .4em;
  margin-left: 5px;
  color: var(--cyan);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-tl {
  margin-top: 26px;
  position: relative;
  padding-left: 22px;
}

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--yellow) 0%, rgba(53, 224, 200, .6) 55%, rgba(107, 124, 138, .28) 100%);
}

.page-about .about-tl__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-tl__node {
  position: relative;
  padding: 0 0 22px 16px;
}

.page-about .about-tl__node::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 7px;
  width: 10px;
  height: 10px;
  background: var(--ink);
  border: 2px solid var(--yellow);
  border-radius: 50%;
  transition: background var(--dur) ease, border-color var(--dur) ease;
}

.page-about .about-tl__node:hover::before {
  background: var(--yellow);
}

.page-about .about-tl__node:last-child {
  padding-bottom: 0;
}

.page-about .about-tl__ver {
  display: inline-block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--ink);
  background: var(--cyan);
  padding: 2px 8px;
  margin-bottom: 8px;
  font-variant-numeric: tabular-nums;
  transition: background var(--dur) ease, color var(--dur) ease;
}

.page-about .about-tl__node:hover .about-tl__ver {
  background: var(--yellow);
}

.page-about .about-tl__name {
  margin: 0 0 6px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 15.5px;
  color: var(--chalk);
}

.page-about .about-tl__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(244, 247, 245, .78);
  max-width: 58ch;
}

/* ---------- 角色矩阵 ---------- */
.page-about .about-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin-top: 22px;
  border: 1px solid var(--line);
}

.page-about .about-role {
  padding: 20px 18px;
  border-bottom: 1px solid var(--line);
  transition: background var(--dur) ease;
}

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

.page-about .about-role--a { background: rgba(18, 58, 46, .7); }
.page-about .about-role--b { background: rgba(10, 36, 28, .82); }
.page-about .about-role--c { background: rgba(14, 27, 42, .8); }

.page-about .about-role:hover {
  background: rgba(53, 224, 200, .09);
}

.page-about .about-role__count {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(38px, 8vw, 56px);
  line-height: 1;
  color: var(--yellow);
  font-variant-numeric: tabular-nums;
}

.page-about .about-role--b .about-role__count { color: var(--cyan); }
.page-about .about-role--c .about-role__count { color: var(--chalk); }

.page-about .about-role__name {
  margin: 0 0 8px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 16px;
  color: var(--chalk);
  letter-spacing: .01em;
}

.page-about .about-role__duty {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(244, 247, 245, .78);
  max-width: 44ch;
}

/* ---------- 边界与勘误 ---------- */
.page-about .about-alert {
  margin-top: 22px;
}

.page-about .about-alert__title {
  margin: 0 0 8px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 15px;
  color: var(--chalk);
}

.page-about .about-alert p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: rgba(244, 247, 245, .84);
  max-width: 62ch;
}

.page-about .about-fix {
  margin-top: 28px;
}

.page-about .about-fix__name {
  margin: 0 0 4px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: 16.5px;
  color: var(--chalk);
}

.page-about .about-fix .about-steps--compact {
  margin-top: 14px;
}

.page-about .about-fix .about-step__name {
  font-size: 15px;
  color: var(--cyan);
}

/* ---------- 行动区 ---------- */
.page-about .about-cta {
  margin-top: 30px;
  padding: 22px 18px;
  background: var(--turf);
  border-left: 4px solid var(--yellow);
}

.page-about .about-cta__text {
  margin: 0 0 16px;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(244, 247, 245, .88);
  max-width: 56ch;
}

.page-about .about-cta__row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta__row .btn {
  text-decoration: none;
}

.page-about .about-sec--last {
  padding-bottom: 0;
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 620px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-stat {
    border-bottom: 0;
    border-left: 1px solid var(--line);
    padding: 16px 16px;
  }

  .page-about .about-stat:first-child {
    border-left: 0;
    padding-left: 0;
  }

  .page-about .about-toc__list {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-about .about-steps {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-step {
    border-bottom: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .about-step:first-child {
    border-left: 0;
  }

  .page-about .about-fix .about-steps--compact {
    grid-template-columns: 1fr;
  }

  .page-about .about-fix .about-step {
    border-left: 0;
    border-bottom: 1px solid var(--line);
  }

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

  .page-about .about-metrics {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-metric {
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    gap: 10px;
    border-bottom: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .about-metric:first-child {
    border-left: 0;
  }

  .page-about .about-roles {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-role {
    border-bottom: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .about-role:first-child {
    border-left: 0;
  }

  .page-about .about-pairs {
    grid-template-columns: repeat(2, 1fr);
    gap: 0 28px;
  }

  .page-about .about-split {
    grid-template-columns: repeat(2, 1fr);
    gap: 0 28px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 1024px) {
  .page-about .about-hero {
    padding-top: 40px;
  }

  .page-about .about-hero .wrap {
    gap: 20px;
  }

  .page-about .about-banner {
    margin-top: 30px;
  }

  .page-about .about-layout {
    display: grid;
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 0 48px;
    align-items: start;
    padding-top: 46px;
    padding-bottom: 84px;
  }

  .page-about .about-toc {
    position: sticky;
    top: 132px;
    margin-bottom: 0;
    max-height: calc(100vh - 170px);
    overflow-y: auto;
  }

  .page-about .about-toc__list {
    grid-template-columns: 1fr;
  }

  .page-about .about-sec {
    padding: 42px 0 48px;
  }

  .page-about .about-line {
    grid-template-columns: 64px 1fr;
    gap: 20px;
    padding: 20px 0 20px 18px;
  }

  .page-about .about-line__no {
    font-size: 20px;
  }

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

  .page-about .about-line__body p {
    font-size: 15px;
  }

  .page-about .about-sec .prose p {
    font-size: 16.5px;
  }

  .page-about .about-step {
    padding: 22px 22px;
  }

  .page-about .about-figure {
    margin-top: 30px;
  }

  .page-about .about-figure--wide {
    max-width: 88%;
  }

  .page-about .about-figure--side {
    max-width: 82%;
    margin-top: 34px;
  }

  .page-about .board {
    margin-top: 34px;
  }

  .page-about .about-tl {
    padding-left: 30px;
    margin-top: 34px;
  }

  .page-about .about-tl__node {
    padding-left: 22px;
    padding-bottom: 26px;
  }

  .page-about .about-tl__node::before {
    left: -35px;
  }

  .page-about .about-cta {
    padding: 26px 24px;
  }
}

/* ---------- 宽屏 ---------- */
@media (min-width: 1320px) {
  .page-about .about-layout {
    grid-template-columns: 248px minmax(0, 1fr);
    gap: 0 64px;
  }

  .page-about .about-sec .prose p {
    font-size: 17px;
  }
}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-toc__list a,
  .page-about .about-line,
  .page-about .about-step,
  .page-about .about-metric,
  .page-about .about-role,
  .page-about .about-tl__node::before,
  .page-about .about-tl__ver,
  .page-about .board__item summary,
  .page-about .about-sec .src a {
    transition: none;
  }
}