.page-about {
  --about-rail: 268px;
  --about-gap: clamp(1.75rem, 4vw, 3.5rem);
  background: var(--navy);
  color: var(--paper);
  padding-bottom: clamp(3rem, 7vw, 6rem);
}

.page-about .breadcrumb {
  padding-block: clamp(1rem, 2.5vw, 1.75rem) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead {
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.5rem);
  padding-block: clamp(1.25rem, 3vw, 2rem) clamp(2rem, 4.5vw, 3rem);
}

.page-about .about-masthead h1 {
  margin: 0.6rem 0 0;
  font-size: clamp(1.95rem, 4.8vw, 3.75rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.01em;
  max-width: 22ch;
}

.page-about .about-masthead__lede {
  margin: clamp(0.9rem, 2vw, 1.35rem) 0 0;
  max-width: 34em;
  color: var(--soft);
  font-size: clamp(1rem, 1.15vw, 1.115rem);
  line-height: 1.75;
}

.page-about .about-masthead__pills {
  list-style: none;
  margin: clamp(1.1rem, 2.4vw, 1.6rem) 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.page-about .about-masthead__pills li {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--mist);
  border: 1px solid var(--line);
  border-radius: 2px;
  padding: 0.35rem 0.6rem;
  background: rgba(18, 50, 92, 0.55);
}

.page-about .about-masthead__shot {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 8px 8px 0 rgba(5, 15, 32, 0.65);
}

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

@media (min-width: 900px) {
  .page-about .about-masthead {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
  }
}

/* ---------- 数字带 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: var(--about-gap);
}

.page-about .about-stats__cell {
  background: var(--abyss);
  padding: clamp(0.9rem, 2vw, 1.4rem) clamp(1rem, 2vw, 1.5rem);
}

.page-about .about-stats__value {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.7rem, 3.4vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-stats__label {
  display: block;
  margin-top: 0.5rem;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--mist);
}

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

/* ---------- 双栏骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.5rem);
}

.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: var(--about-gap);
  min-width: 0;
}

.page-about .about-section {
  scroll-margin-top: calc(var(--header-h-condensed) + 1.5rem);
}

.page-about .about-section .section-head {
  margin-bottom: clamp(1rem, 2.5vw, 1.6rem);
}

.page-about .about-section h2 {
  margin: 0.5rem 0 0;
}

.page-about .about-text {
  max-width: 34em;
  margin: 0;
  color: var(--soft);
  line-height: 1.75;
}

.page-about .about-text + .about-text {
  margin-top: 1em;
}

/* ---------- 左侧索引 ---------- */
.page-about .about-rail {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  min-width: 0;
}

.page-about .about-rail__title {
  margin: 0 0 0.6rem;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--mist);
  text-transform: uppercase;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0.4rem;
  display: flex;
  gap: 0.4rem;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__list li {
  flex: 0 0 auto;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.7rem;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--stand);
  color: var(--soft);
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  border-color: var(--orange);
  color: var(--paper);
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  color: var(--orange);
}

.page-about .about-scale {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.15rem;
  border-left: 1px solid var(--line);
}

.page-about .about-scale li {
  position: relative;
  padding-block: 0.45rem;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  color: var(--soft);
}

.page-about .about-scale li::before {
  content: "";
  position: absolute;
  left: calc(-1.15rem - 4.5px);
  top: 50%;
  transform: translateY(-50%);
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--navy);
  border: 1px solid var(--orange);
}

.page-about .about-scale li:last-child::before {
  background: var(--green);
  border-color: var(--green);
}

@media (min-width: 1040px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 4rem);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h-condensed) + 1.5rem);
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0.15rem;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__link {
    white-space: normal;
    background: transparent;
    border-color: transparent;
    border-left: 2px solid var(--line);
    border-radius: 0;
    padding: 0.45rem 0.6rem;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-left-color: var(--orange);
    background: rgba(18, 50, 92, 0.6);
  }
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: clamp(1.25rem, 3vw, 2rem) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(0.85rem, 1.6vw, 1.15rem);
}

.page-about .about-timeline__item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--stand);
  padding: clamp(0.9rem, 1.8vw, 1.35rem) clamp(1rem, 1.8vw, 1.5rem);
  box-shadow: 5px 5px 0 rgba(4, 12, 26, 0.55);
  display: grid;
  gap: 0.5rem;
}

.page-about .about-timeline__year {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 15px;
  font-weight: 700;
  color: var(--orange);
  letter-spacing: 0.02em;
}

.page-about .about-timeline__item h3 {
  margin: 0 0 0.35rem;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-timeline__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--soft);
}

@media (min-width: 780px) {
  .page-about .about-timeline {
    padding-right: clamp(0px, 2.2vw, 34px);
  }

  .page-about .about-timeline__item {
    grid-template-columns: 118px minmax(0, 1fr);
    align-items: start;
    gap: 1.25rem;
  }

  .page-about .about-timeline__item:nth-child(even) {
    transform: translateX(clamp(8px, 2vw, 34px));
  }
}

/* ---------- 团队环形 ---------- */
.page-about .about-ring {
  display: grid;
  gap: clamp(1.1rem, 2.5vw, 2rem);
  margin-top: clamp(1.25rem, 3vw, 2rem);
  align-items: center;
}

.page-about .about-ring svg {
  display: block;
  width: min(210px, 62vw);
  height: auto;
  margin-inline: auto;
}

.page-about .about-ring__seg {
  fill: none;
  stroke-width: 17;
  transition: stroke-width var(--dur) var(--ease);
}

.page-about .about-ring__seg:hover {
  stroke-width: 24;
}

.page-about .about-ring__seg--a { stroke: var(--orange); }
.page-about .about-ring__seg--b { stroke: var(--cyan); }
.page-about .about-ring__seg--c { stroke: var(--green); }
.page-about .about-ring__seg--d { stroke: var(--amber); }

.page-about .about-ring__center {
  fill: var(--paper);
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
}

.page-about .about-ring__sub {
  fill: var(--mist);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.page-about .about-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.page-about .about-roles li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.7rem;
  align-items: start;
}

.page-about .about-roles p {
  margin: 0;
}

.page-about .about-roles__dot {
  width: 10px;
  height: 10px;
  margin-top: 0.45rem;
  border-radius: 2px;
}

.page-about .about-roles__dot--a { background: var(--orange); }
.page-about .about-roles__dot--b { background: var(--cyan); }
.page-about .about-roles__dot--c { background: var(--green); }
.page-about .about-roles__dot--d { background: var(--amber); }

.page-about .about-roles__name {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-roles__count {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  font-weight: 500;
  color: var(--orange);
  margin-left: 0.45rem;
}

.page-about .about-roles__desc {
  display: block;
  margin-top: 0.25rem;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 760px) {
  .page-about .about-ring {
    grid-template-columns: 210px minmax(0, 1fr);
    gap: clamp(1.5rem, 3vw, 2.5rem);
  }
}

.page-about .about-team-shot {
  margin: clamp(1.5rem, 3vw, 2.25rem) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 rgba(5, 15, 32, 0.6);
}

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

.page-about .about-team-shot .figure__caption {
  padding: 0.6rem clamp(0.8rem, 1.5vw, 1.1rem);
  font-size: 12.5px;
  color: var(--mist);
  background: var(--abyss);
}

/* ---------- 字段表 ---------- */
.page-about .about-fields {
  margin-top: clamp(1rem, 2vw, 1.5rem);
}

.page-about .about-fields caption {
  text-align: left;
  padding-bottom: 0.75rem;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .about-fields th[scope="row"] {
  color: var(--paper);
  font-weight: 700;
  white-space: nowrap;
}

/* ---------- 阅读取舍 ---------- */
.page-about .about-choices {
  list-style: none;
  margin: clamp(1rem, 2vw, 1.5rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-choices li {
  background: var(--stand);
  padding: clamp(0.9rem, 1.9vw, 1.35rem);
}

.page-about .about-choices h3 {
  margin: 0 0 0.35rem;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-choices h3::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 0.5rem;
  background: var(--orange);
  transform: translateY(-1px);
}

.page-about .about-choices p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 820px) {
  .page-about .about-choices {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 投入方向 ---------- */
.page-about .about-roadmap {
  position: relative;
  overflow: hidden;
  margin-top: clamp(1rem, 2.5vw, 1.75rem);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--abyss);
}

.page-about .about-roadmap__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.2;
}

.page-about .about-roadmap__inner {
  position: relative;
  display: grid;
  gap: clamp(1.1rem, 2.5vw, 1.9rem);
  padding: clamp(1.1rem, 3vw, 2.2rem);
}

.page-about .about-roadmap__lede {
  max-width: 34em;
}

.page-about .about-roadmap__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.95rem;
}

.page-about .about-roadmap__list li {
  border-left: 2px solid var(--orange);
  padding-left: 0.85rem;
}

.page-about .about-roadmap__list strong {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-roadmap__list span {
  display: block;
  margin-top: 0.25rem;
  font-size: 14px;
  line-height: 1.7;
  color: var(--soft);
}

@media (min-width: 880px) {
  .page-about .about-roadmap__inner {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
    align-items: start;
  }
}

/* ---------- 下一步 ---------- */
.page-about .about-cta {
  display: grid;
  gap: var(--gap);
  margin-top: var(--about-gap);
}

.page-about .about-cta__item {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.page-about .about-cta__item h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-cta__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-cta__item .btn {
  margin-top: auto;
  align-self: flex-start;
}

@media (min-width: 700px) {
  .page-about .about-cta {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1120px) {
  .page-about .about-cta {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}