.page-about {
  --about-rail: 12rem;
  background: var(--night);
  color: var(--text);
  padding-bottom: clamp(2.5rem, 6vw, 5rem);
}

/* ---------- 页头 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(1.4rem, 3.5vw, 2.6rem) 0 clamp(1.6rem, 4vw, 2.8rem);
  border-bottom: 1px solid var(--line-dark);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "2016—2025";
  position: absolute;
  right: 0;
  bottom: 0.2rem;
  font-family: var(--font-num);
  font-size: clamp(2.2rem, 7vw, 4.6rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: rgba(216, 201, 172, 0.07);
  pointer-events: none;
  z-index: 0;
}

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

.page-about .about-hero__eyebrow {
  margin: 0 0 0.9rem;
  color: var(--cyan);
  letter-spacing: 0.2em;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5.4vw, 3.6rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--paper);
  margin: 0 0 1.1rem;
  max-width: 22ch;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(0.98rem, 1.3vw, 1.08rem);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-stats {
  list-style: none;
  margin: clamp(1.6rem, 4vw, 2.6rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.page-about .about-stats .stat {
  min-width: 0;
  padding-left: 0.9rem;
  border-left: 2px solid var(--turf);
}

.page-about .about-stats .stat__value {
  display: block;
  font-size: clamp(1.4rem, 3.4vw, 2.1rem);
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-stats .stat__label {
  display: block;
  margin-top: 0.3rem;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--stand);
}

@media (min-width: 760px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.4rem;
  }
}

/* ---------- 档案式纵向布局 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 0;
  padding-top: clamp(1rem, 3vw, 2rem);
}

.page-about .about-rail {
  display: none;
}

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

.page-about .about-rail__title {
  margin: 0 0 0.9rem;
  color: var(--stand);
  letter-spacing: 0.2em;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1rem;
  border-left: 1px solid var(--line-dark);
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

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

.page-about .about-rail__item::before {
  content: "";
  position: absolute;
  left: -1rem;
  top: 0.62em;
  width: 0.5rem;
  height: 1px;
  background: var(--stand);
  opacity: 0.65;
}

.page-about .about-rail__item:has(.is-in)::before,
.page-about .about-rail__item:has(.is-active)::before {
  background: var(--cyan);
  opacity: 1;
  width: 0.75rem;
}

.page-about .about-rail__list .chapter-link {
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-decoration: none;
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(1.8rem, 4vw, 3.6rem);
    padding-top: 2.4rem;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 6.2rem;
    align-self: start;
    padding-top: 3.2rem;
  }
}

/* ---------- 章节骨架 ---------- */
.page-about .about-section {
  padding: clamp(2rem, 4.5vw, 3.2rem) 0;
  border-bottom: 1px solid var(--line-dark);
  scroll-margin-top: 6rem;
}

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

.page-about .about-section__head {
  margin-bottom: clamp(1.2rem, 2.5vw, 1.8rem);
}

.page-about .about-section__eyebrow {
  display: block;
  margin-bottom: 0.6rem;
  color: var(--stand);
  letter-spacing: 0.2em;
}

.page-about .about-section h2 {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.6vw, 1.85rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: 0.01em;
  color: var(--paper);
  margin: 0 0 0.6rem;
}

.page-about .about-section__intro {
  margin: 0;
  max-width: 64ch;
  font-size: 0.96rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 200, 0.4);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  border-bottom-color: var(--cyan);
}

/* ---------- 01 读者 ---------- */
.page-about .audience {
  display: grid;
}

.page-about .audience-row {
  display: grid;
  gap: 0.35rem 1.2rem;
  padding: 1.2rem 0;
  border-bottom: 1px dashed var(--line-dark);
}

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

.page-about .audience-row__no {
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .audience-row__title {
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--paper);
  margin: 0;
}

.page-about .audience-row__text {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--muted);
}

@media (min-width: 760px) {
  .page-about .audience-row {
    grid-template-columns: 3rem 11.5rem minmax(0, 1fr);
    align-items: baseline;
    padding: 1.4rem 0.6rem 1.4rem 0;
    transition: background 0.2s ease;
  }

  .page-about .audience-row:hover {
    background: linear-gradient(90deg, rgba(53, 224, 200, 0.07), transparent 62%);
  }

  .page-about .audience-row__no {
    padding-top: 0.15rem;
  }
}

/* ---------- 02 团队矩阵 ---------- */
.page-about .team-matrix {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.5rem;
  max-width: 30rem;
  margin: 0 0 1.8rem;
}

.page-about .team-cell {
  position: relative;
  aspect-ratio: 1 / 1;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line-dark);
  border-radius: 4px;
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  outline: none;
}

.page-about .team-cell--entry {
  background: rgba(53, 224, 200, 0.14);
  border-color: rgba(53, 224, 200, 0.42);
  color: var(--cyan);
}

.page-about .team-cell--proof {
  background: rgba(232, 176, 75, 0.14);
  border-color: rgba(232, 176, 75, 0.42);
  color: var(--gold);
}

.page-about .team-cell--edit {
  background: rgba(242, 233, 216, 0.12);
  border-color: rgba(242, 233, 216, 0.38);
  color: var(--paper);
}

.page-about .team-cell:hover,
.page-about .team-cell:focus-visible {
  border-color: var(--cyan);
  outline: 1px solid rgba(53, 224, 200, 0.6);
  outline-offset: 1px;
}

.page-about .team-cell__note {
  display: none;
}

.page-about .team-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .team-roles__item {
  display: grid;
  grid-template-columns: 3rem minmax(0, 1fr);
  gap: 0 1rem;
  padding: 1.1rem 0;
  border-top: 1px solid var(--line-dark);
}

.page-about .team-roles__no {
  font-size: 1.2rem;
  line-height: 1.2;
  color: var(--gold);
}

.page-about .team-roles__title {
  margin: 0 0 0.4rem;
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .team-roles__body p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .team-cell__note {
    display: block;
    position: absolute;
    left: 50%;
    bottom: calc(100% + 10px);
    transform: translate(-50%, 4px);
    width: 11rem;
    padding: 0.6rem 0.7rem;
    background: var(--paper);
    color: var(--ink);
    border: 1px solid var(--paper-deep);
    border-radius: 3px;
    box-shadow: var(--shadow-paper);
    font-size: 0.72rem;
    line-height: 1.55;
    letter-spacing: 0;
    text-align: left;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s;
    z-index: 6;
  }

  .page-about .team-cell:hover .team-cell__note,
  .page-about .team-cell:focus-visible .team-cell__note {
    opacity: 1;
    visibility: visible;
    transform: translate(-50%, 0);
  }
}

/* ---------- 03 流程时间轴 ---------- */
.page-about .about-flow__grid {
  display: grid;
  gap: clamp(1.4rem, 3vw, 2.4rem);
}

.page-about .about-flow__figure {
  margin: 0;
}

.page-about .about-flow__stack {
  display: grid;
  gap: 0.7rem;
}

.page-about .flow-step {
  position: relative;
  border: 1px solid var(--line-dark);
  border-radius: 5px;
  background: linear-gradient(180deg, rgba(16, 49, 43, 0.9), rgba(11, 30, 45, 0.72));
  transition: border-color 0.18s ease;
}

.page-about .flow-step[open] {
  border-color: rgba(53, 224, 200, 0.55);
}

.page-about .flow-step__summary {
  position: relative;
  display: grid;
  gap: 0.22rem;
  padding: 0.85rem 2.2rem 0.85rem 1rem;
  cursor: pointer;
  list-style: none;
}

.page-about .flow-step__summary::-webkit-details-marker {
  display: none;
}

.page-about .flow-step__summary::after {
  content: "+";
  position: absolute;
  top: 0.7rem;
  right: 0.85rem;
  font-family: var(--font-num);
  font-size: 1rem;
  line-height: 1;
  color: var(--stand);
}

.page-about .flow-step[open] .flow-step__summary::after {
  content: "–";
  color: var(--cyan);
}

.page-about .flow-step__no {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .flow-step__title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .flow-step__time {
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .flow-step__body {
  margin: 0;
  padding: 0 1rem 1rem;
  font-size: 0.87rem;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .about-flow__grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    align-items: start;
  }
}

@media (min-width: 1160px) {
  .page-about .about-flow__stack {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0.6rem;
    align-items: start;
  }

  .page-about .flow-step__summary {
    padding: 0.8rem 0.8rem 0.8rem 0.85rem;
  }

  .page-about .flow-step__summary::after {
    top: 0.6rem;
    right: 0.6rem;
  }

  .page-about .flow-step__title {
    font-size: 0.9rem;
  }
}

/* ---------- 04 发展历程 ---------- */
.page-about .about-decade {
  position: relative;
  overflow: hidden;
  padding: 0;
  border-bottom: 1px solid var(--line-dark);
}

.page-about .about-decade__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .about-decade__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.26;
  filter: saturate(0.45) contrast(1.05);
}

.page-about .about-decade::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(180deg, rgba(11, 30, 45, 0.88), rgba(16, 49, 43, 0.94));
  pointer-events: none;
}

.page-about .about-decade__inner {
  position: relative;
  z-index: 2;
  padding: clamp(2rem, 4.5vw, 3.2rem) clamp(1rem, 3vw, 2.2rem);
}

.page-about .year-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1rem;
  counter-reset: none;
}

.page-about .year-item {
  padding: 1.05rem 1.1rem 1.15rem;
  background: var(--paper);
  color: var(--ink);
  border: 1px solid var(--paper-deep);
  border-radius: 3px;
  box-shadow: 5px 5px 0 rgba(11, 30, 45, 0.42), 8px 8px 0 rgba(216, 201, 172, 0.14);
}

.page-about .year-item__year {
  display: block;
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--brick);
}

.page-about .year-item__title {
  margin: 0.5rem 0 0.4rem;
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .year-item p {
  margin: 0;
  font-size: 0.87rem;
  line-height: 1.75;
  color: rgba(16, 20, 24, 0.78);
}

@media (min-width: 900px) {
  .page-about .year-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.2rem 2.4rem;
  }

  .page-about .year-item:nth-child(odd) {
    transform: translateY(0.5rem);
  }
}

/* ---------- 05 教练席档案 ---------- */
.page-about .about-coach__figure {
  margin: 0 0 clamp(1.4rem, 3vw, 2.2rem);
}

.page-about .about-coach__grid {
  display: grid;
  gap: clamp(1.4rem, 3vw, 2.4rem);
}

.page-about .about-coach__text p {
  margin: 0 0 1rem;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--muted);
  max-width: 60ch;
}

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

.page-about .coach-facts {
  margin: 0;
  border-top: 1px solid var(--line-dark);
}

.page-about .coach-facts__row {
  display: grid;
  grid-template-columns: minmax(0, 6.5rem) minmax(0, 1fr);
  gap: 0.9rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--line-dark);
}

.page-about .coach-facts dt {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--gold);
  padding-top: 0.15rem;
}

.page-about .coach-facts dd {
  margin: 0;
  font-size: 0.87rem;
  line-height: 1.7;
  color: var(--text);
}

@media (min-width: 900px) {
  .page-about .about-coach__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }
}

/* ---------- 06 本地协作 ---------- */
.page-about .about-qingdao {
  max-width: 66ch;
}

.page-about .about-qingdao p {
  margin: 0 0 1.1rem;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-qingdao__links {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-qingdao__link {
  display: grid;
  gap: 0.2rem;
  padding: 0.9rem 0;
  border-top: 1px solid var(--line-dark);
}

.page-about .about-qingdao__link a {
  color: var(--cyan);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 700;
}

.page-about .about-qingdao__link a:hover,
.page-about .about-qingdao__link a:focus-visible {
  text-decoration: underline;
}

.page-about .about-qingdao__link span {
  font-size: 0.82rem;
  color: var(--stand);
  letter-spacing: 0.02em;
}

@media (min-width: 720px) {
  .page-about .about-qingdao__link {
    grid-template-columns: 8rem minmax(0, 1fr);
    align-items: baseline;
  }
}

/* ---------- 收尾 ---------- */
.page-about .about-outro p {
  margin: 0 0 1.6rem;
  max-width: 64ch;
  font-size: 0.96rem;
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

@media (max-width: 719px) {
  .page-about .about-hero::after {
    display: none;
  }

  .page-about .team-matrix {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 0.35rem;
  }

  .page-about .team-roles__item {
    grid-template-columns: 2.4rem minmax(0, 1fr);
    gap: 0 0.8rem;
  }

  .page-about .coach-facts__row {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.3rem;
  }
}