.page-about {
  --ab-navy: #0A192F;
  --ab-cream: #F5F0E8;
  --ab-brown: #2B1D14;
  --ab-orange: #FF5C00;
  --ab-green: #39FF88;
  --ab-line: #254D6A;
  --ab-steel: #8896A4;
  background:
    repeating-linear-gradient(0deg, rgba(10,25,47,0.014) 0, rgba(10,25,47,0.014) 1px, transparent 1px, transparent 4px),
    radial-gradient(circle at 82% 8%, rgba(10,25,47,0.05) 0%, transparent 28%),
    radial-gradient(circle at 20% 72%, rgba(255,92,0,0.04) 0%, transparent 24%),
    var(--ab-cream);
  color: var(--ab-brown);
  font-family: var(--font-body);
  line-height: 1.7;
  max-width: 1320px;
  margin: 0 auto;
  padding: 24px 18px 72px;
}

/* ===== 品牌引言 ===== */
.page-about .ab-intro {
  position: relative;
  background: linear-gradient(135deg, var(--ab-navy) 0%, #12335A 62%, var(--ab-line) 100%);
  color: #fff;
  padding: 42px 22px 44px;
  border-radius: 2px;
  overflow: hidden;
  box-shadow: 0 14px 40px rgba(10,25,47,0.18);
  margin-bottom: 52px;
}
.page-about .ab-intro::before {
  content: "LEYU SPORTS";
  position: absolute;
  right: -16px;
  bottom: 70px;
  font-family: var(--font-mono);
  font-size: clamp(60px, 10vw, 116px);
  font-weight: 800;
  letter-spacing: -0.06em;
  line-height: 1;
  color: rgba(57,255,136,0.10);
  white-space: nowrap;
  transform: rotate(-8deg);
  pointer-events: none;
}
.page-about .ab-intro::after {
  content: "";
  position: absolute;
  left: 22px;
  bottom: 24px;
  width: 140px;
  height: 3px;
  background: var(--ab-green);
  box-shadow: 0 0 24px rgba(57,255,136,0.6);
}
.page-about .ab-intro__kicker {
  display: inline-block;
  border: 1px solid rgba(57,255,136,0.36);
  padding: 4px 12px;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--ab-green);
  text-transform: uppercase;
  margin-bottom: 18px;
  background: rgba(10,25,47,0.32);
  position: relative;
  z-index: 1;
}
.page-about .ab-intro h1 {
  font-family: var(--font-display);
  font-size: clamp(26px, 5vw, 48px);
  line-height: 1.14;
  font-weight: 900;
  letter-spacing: -0.02em;
  margin: 0 0 20px;
  max-width: 820px;
  position: relative;
  z-index: 1;
}
.page-about .ab-intro__lede {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255,255,255,0.82);
  max-width: 660px;
  margin: 0;
  position: relative;
  z-index: 1;
}
.page-about .ab-intro__aside {
  margin-top: 30px;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  max-width: 660px;
  position: relative;
  z-index: 1;
}
.page-about .ab-intro__fact {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.16);
  padding: 14px 12px;
  border-radius: 2px;
}
.page-about .ab-intro__fact-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.6);
  margin-bottom: 4px;
}
.page-about .ab-intro__fact strong {
  display: block;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1.2;
  color: var(--ab-green);
}

/* ===== 目录 ===== */
.page-about .ab-toc {
  margin-bottom: 56px;
  border: 1px solid var(--ab-line);
  border-left: 4px solid var(--ab-orange);
  padding: 18px 16px;
  background: rgba(255,255,255,0.5);
}
.page-about .ab-toc .section-kicker {
  margin-bottom: 12px;
}
.page-about .ab-toc__links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
}
.page-about .ab-toc__link {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ab-brown);
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease;
  border-bottom: 2px solid transparent;
  padding: 2px 0;
}
.page-about .ab-toc__link span {
  font-weight: 700;
  color: var(--ab-orange);
  margin-right: 3px;
}
.page-about .ab-toc__link:hover,
.page-about .ab-toc__link:focus-visible {
  color: var(--ab-orange);
  border-color: var(--ab-orange);
  outline: none;
}

/* ===== 章节基础 ===== */
.page-about .ab-section {
  margin-bottom: 64px;
  padding-top: 20px;
  border-top: 1px solid var(--ab-line);
  scroll-margin-top: 24px;
}
.page-about .ab-section__side {
  margin-bottom: 14px;
  display: flex;
  align-items: flex-start;
}
.page-about .ab-section__num {
  font-family: var(--font-mono);
  font-size: 64px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.08em;
  color: var(--ab-orange);
  opacity: 0.9;
  display: block;
}
.page-about .ab-section__body .section-kicker {
  margin-bottom: 4px;
}
.page-about .ab-section h2 {
  font-family: var(--font-display);
  font-size: clamp(24px, 4vw, 36px);
  line-height: 1.22;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 0 0 14px;
}
.page-about .ab-section__lead {
  font-size: 14px;
  color: var(--ab-steel);
  margin: 0 0 24px;
  max-width: 640px;
}
.page-about .ab-section__columns p {
  font-size: 14px;
  color: #556;
  margin: 0 0 16px;
}
.page-about .ab-section__columns p:last-child {
  margin-bottom: 0;
}

/* ===== 01 原则卡片 ===== */
.page-about .ab-principles {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}
.page-about .ab-principles__item {
  background: rgba(255,255,255,0.65);
  border: 1px solid var(--ab-line);
  border-radius: 2px;
  padding: 20px 18px;
  position: relative;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.page-about .ab-principles__item:hover,
.page-about .ab-principles__item:focus-within {
  transform: translateX(6px);
  box-shadow: 5px 5px 0 rgba(10,25,47,0.12);
}
.page-about .ab-principles__item .section-index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--ab-orange);
  background: rgba(255,92,0,0.08);
  padding: 2px 8px;
  border-radius: 2px;
}
.page-about .ab-principles__item h3 {
  font-size: 17px;
  font-weight: 700;
  margin: 12px 0 6px;
  font-family: var(--font-display);
}
.page-about .ab-principles__item p {
  font-size: 13px;
  color: #556;
  line-height: 1.7;
  margin: 0;
}

/* ===== 02 时间轴 ===== */
.page-about .ab-timeline {
  margin: 26px 0 0;
}
.page-about .ab-timeline__list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .ab-timeline__item {
  position: relative;
  padding: 0 0 26px 26px;
  border-left: 1px solid var(--ab-line);
  margin-left: 10px;
}
.page-about .ab-timeline__item:last-child {
  padding-bottom: 0;
}
.page-about .ab-timeline__item::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 6px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--ab-cream);
  border: 3px solid var(--ab-orange);
  transition: background 0.18s ease, box-shadow 0.18s ease;
}
.page-about .ab-timeline__item:hover::before,
.page-about .ab-timeline__item:focus-within::before {
  background: var(--ab-orange);
  box-shadow: 0 0 0 7px rgba(255,92,0,0.14);
}
.page-about .ab-timeline__year {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--ab-orange);
  letter-spacing: 0.04em;
  display: inline-block;
  margin-bottom: 6px;
}
.page-about .ab-timeline__content {
  background: rgba(255,255,255,0.55);
  border: 1px solid rgba(37,77,106,0.35);
  border-radius: 2px;
  padding: 16px;
  transition: border-color 0.18s ease, background 0.18s ease;
}
.page-about .ab-timeline__item:hover .ab-timeline__content,
.page-about .ab-timeline__item:focus-within .ab-timeline__content {
  border-color: var(--ab-orange);
  background: #ffffff;
}
.page-about .ab-timeline__content h3 {
  font-size: 15px;
  font-weight: 700;
  margin: 0 0 6px;
}
.page-about .ab-timeline__content p {
  font-size: 13px;
  color: #556;
  line-height: 1.65;
  margin: 0;
}

/* ===== 图片容器 ===== */
.page-about .ab-figure {
  margin: 28px 0 0;
  border: 1px solid var(--ab-line);
  border-radius: 2px;
  padding: 8px;
  background: rgba(255,255,255,0.4);
}
.page-about .ab-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 1px;
}
.page-about .ab-figure figcaption {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ab-steel);
  margin-top: 8px;
  padding-left: 8px;
  border-left: 3px solid var(--ab-orange);
  line-height: 1.5;
}

/* ===== 03 数据能力 ===== */
.page-about .ab-data {
  display: grid;
  gap: 20px;
}
.page-about .ab-data__stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}
.page-about .ab-data__stat {
  background: var(--ab-navy);
  padding: 18px 14px;
  border-radius: 2px;
  position: relative;
  overflow: hidden;
  color: #fff;
  transition: transform 0.18s ease;
}
.page-about .ab-data__stat:hover {
  transform: translateY(-3px);
}
.page-about .ab-data__stat::before {
  content: "";
  position: absolute;
  right: -18px;
  top: -18px;
  width: 48px;
  height: 48px;
  background: rgba(57,255,136,0.16);
  border-radius: 50%;
}
.page-about .ab-data__stat::after {
  content: "";
  position: absolute;
  right: 10px;
  bottom: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ab-green);
  opacity: 0.7;
}
.page-about .ab-data__value {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 800;
  line-height: 1.1;
  color: var(--ab-green);
}
.page-about .ab-data__value small {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  margin-left: 2px;
}
.page-about .ab-data__label {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  color: rgba(255,255,255,0.62);
  margin-top: 6px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* 数据流程动画 */
.page-about .ab-pipeline {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 14px 12px;
  background: rgba(10,25,47,0.06);
  border: 1px dashed var(--ab-line);
  border-radius: 2px;
}
.page-about .ab-pipeline__node {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ab-navy);
  background: rgba(255,255,255,0.8);
  border: 1px solid var(--ab-line);
  padding: 6px 10px;
  white-space: nowrap;
  border-radius: 2px;
}
.page-about .ab-pipeline__flow {
  flex: 1;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--ab-green), transparent);
  background-size: 200% 100%;
  animation: page-about-flow 2.2s linear infinite;
}
@keyframes page-about-flow {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* 数据行 */
.page-about .ab-data__rows {
  display: grid;
  gap: 12px;
}
.page-about .ab-data__row {
  border: 1px solid var(--ab-line);
  border-radius: 2px;
  padding: 18px 16px;
  background: rgba(255,255,255,0.5);
  border-left: 3px solid var(--ab-line);
  transition: border-color 0.18s ease, background 0.18s ease;
}
.page-about .ab-data__row:hover {
  border-left-color: var(--ab-orange);
  background: rgba(255,255,255,0.8);
}
.page-about .ab-data__row .section-index {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ab-orange);
}
.page-about .ab-data__row h3 {
  font-size: 16px;
  font-weight: 700;
  margin: 6px 0 8px;
  font-family: var(--font-display);
}
.page-about .ab-data__row p {
  font-size: 13px;
  color: #556;
  line-height: 1.7;
  margin: 0;
}

/* ===== 04 全端适配 ===== */
.page-about .ab-adapt {
  display: grid;
  gap: 20px;
}
.page-about .ab-adapt__devices {
  display: grid;
  gap: 12px;
}
.page-about .ab-adapt__device {
  border: 1px solid var(--ab-line);
  border-top: 3px solid var(--ab-orange);
  background: rgba(255,255,255,0.65);
  padding: 18px;
  transition: transform 0.18s ease;
}
.page-about .ab-adapt__device:hover {
  transform: translateY(-3px);
}
.page-about .ab-adapt__device-icon {
  font-size: 28px;
  color: var(--ab-orange);
  display: inline-block;
  opacity: 0.85;
}
.page-about .ab-adapt__device h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  margin: 8px 0 6px;
}
.page-about .ab-adapt__device p {
  font-size: 13px;
  color: #555;
  line-height: 1.65;
  margin: 0;
}
.page-about .ab-adapt__detail {
  background: linear-gradient(135deg, var(--ab-navy) 0%, #163A62 100%);
  border-radius: 2px;
  padding: 20px 18px;
  color: #fff;
}
.page-about .ab-adapt__detail-item {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 10px 0;
  border-bottom: 1px solid rgba(255,255,255,0.12);
}
.page-about .ab-adapt__detail-item:last-child {
  border-bottom: none;
}
.page-about .ab-adapt__detail-item .section-index {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ab-green);
  white-space: nowrap;
  padding-top: 2px;
}
.page-about .ab-adapt__detail-item p {
  font-size: 13px;
  color: rgba(255,255,255,0.82);
  margin: 0;
  line-height: 1.6;
}

/* ===== 05 社区承诺 ===== */
.page-about .ab-community {
  display: grid;
  gap: 20px;
}
.page-about .ab-community__stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}
.page-about .ab-community__stat {
  background: #fff;
  border: 1px solid var(--ab-line);
  padding: 18px 12px;
  text-align: center;
  border-radius: 2px;
}
.page-about .ab-community__stat strong {
  display: block;
  font-family: var(--font-mono);
  font-size: 24px;
  color: var(--ab-orange);
  line-height: 1.1;
}
.page-about .ab-community__stat strong small {
  font-size: 13px;
}
.page-about .ab-community__stat span {
  display: block;
  font-size: 12px;
  color: #555;
  margin-top: 6px;
}
.page-about .ab-community__promise {
  background: var(--ab-navy);
  color: #fff;
  padding: 22px 18px;
  border-radius: 2px;
  position: relative;
  overflow: hidden;
}
.page-about .ab-community__promise::after {
  content: "";
  position: absolute;
  right: -24px;
  top: -24px;
  width: 72px;
  height: 72px;
  background: rgba(57,255,136,0.14);
  border-radius: 50%;
}
.page-about .ab-community__promise h3 {
  font-size: 17px;
  font-weight: 700;
  margin: 0 0 14px;
  color: var(--ab-green);
}
.page-about .ab-community__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}
.page-about .ab-community__list li {
  position: relative;
  padding-left: 18px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(255,255,255,0.85);
}
.page-about .ab-community__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  background: var(--ab-orange);
}

/* ===== 06 团队资质 ===== */
.page-about .ab-team__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}
.page-about .ab-team__card {
  background: rgba(255,255,255,0.65);
  border: 1px solid var(--ab-line);
  border-bottom: 3px solid var(--ab-orange);
  border-radius: 2px;
  padding: 18px 14px;
}
.page-about .ab-team__card .section-index {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ab-orange);
}
.page-about .ab-team__card h3 {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 800;
  margin: 10px 0 4px;
  line-height: 1.1;
}
.page-about .ab-team__card p {
  font-size: 12px;
  color: #555;
  margin: 0;
  line-height: 1.5;
}
.page-about .ab-team__note {
  font-size: 13px;
  color: #556;
  background: rgba(255,255,255,0.5);
  border-left: 4px solid var(--ab-line);
  border-radius: 0 2px 2px 0;
  padding: 14px 16px;
  line-height: 1.7;
}

/* ===== CTA ===== */
.page-about .ab-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

/* ===== 小屏适配 ===== */
@media (max-width: 479px) {
  .page-about .ab-intro__aside {
    grid-template-columns: 1fr;
  }
  .page-about .ab-section__num {
    font-size: 52px;
  }
  .page-about .ab-data__stat {
    padding: 14px 12px;
  }
}

/* ===== 桌面增强 ===== */
@media (min-width: 768px) {
  .page-about {
    padding: 48px max(24px, calc((100vw - 1280px) / 2)) 100px;
  }
  .page-about .ab-intro {
    padding: 72px 56px 72px;
  }
  .page-about .ab-intro h1 {
    font-size: clamp(38px, 4.8vw, 56px);
  }
  .page-about .ab-intro__lede {
    font-size: 16px;
  }
  .page-about .ab-intro__aside {
    gap: 16px;
    max-width: 720px;
  }
  .page-about .ab-intro__fact strong {
    font-size: 24px;
  }

  .page-about .ab-toc {
    display: flex;
    align-items: flex-start;
    gap: 32px;
  }
  .page-about .ab-toc .section-kicker {
    margin-bottom: 0;
    padding-top: 4px;
  }
  .page-about .ab-toc__links {
    flex: 1;
    gap: 12px 24px;
  }

  .page-about .ab-section {
    display: grid;
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 36px;
    margin-bottom: 96px;
  }
  .page-about .ab-section__side {
    margin: 0;
    align-self: start;
    position: sticky;
    top: 24px;
    flex-direction: column;
  }
  .page-about .ab-section__num {
    font-size: 96px;
  }

  .page-about .ab-section__columns {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }
  .page-about .ab-section__columns p:last-child {
    margin-bottom: 0;
  }

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

  .page-about .ab-data {
    gap: 24px;
  }
  .page-about .ab-data__stats {
    grid-template-columns: repeat(4, 1fr);
  }
  .page-about .ab-data__row {
    display: grid;
    grid-template-columns: 130px 1fr;
    gap: 18px;
    align-items: start;
  }

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

  .page-about .ab-community__stats {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .ab-team__grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (min-width: 1024px) {
  .page-about .ab-timeline__list {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 18px;
    position: relative;
    padding-top: 16px;
  }
  .page-about .ab-timeline__item {
    border-left: none;
    border-top: 1px solid var(--ab-line);
    padding: 20px 8px 0 0;
    margin: 0;
  }
  .page-about .ab-timeline__item::before {
    left: 0;
    top: -7px;
  }
}

/* ===== 动效降级 ===== */
@media (prefers-reduced-motion: reduce) {
  .page-about .ab-pipeline__flow {
    animation: none;
    background: var(--ab-green);
    opacity: 0.5;
  }
  .page-about .ab-data__stat:hover,
  .page-about .ab-adapt__device:hover,
  .page-about .ab-principles__item:hover,
  .page-about .ab-timeline__item:hover .ab-timeline__content {
    transform: none;
  }
}