.page-about {
  --ab-cut: 14px;
  --ab-seg-1: rgba(47, 230, 200, 0.92);
  --ab-seg-2: rgba(47, 230, 200, 0.62);
  --ab-seg-3: rgba(47, 230, 200, 0.40);
  --ab-seg-4: rgba(47, 230, 200, 0.24);
  display: block;
  padding: clamp(14px, 2.4vw, 28px) 0 clamp(32px, 5vw, 68px);
  color: var(--text);
}

.page-about .about-shell {
  display: block;
}

/* ---------- 首屏拼贴 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background:
    radial-gradient(120% 130% at 88% 0%, rgba(47, 230, 200, 0.20), transparent 60%),
    linear-gradient(180deg, rgba(18, 23, 29, 0.55), var(--ink) 94%);
  clip-path: polygon(var(--ab-cut) 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%, 0 var(--ab-cut));
}

.page-about .about-hero__media {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.30;
  filter: saturate(0.65) contrast(1.08);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 26px 20px 44px;
}

.page-about .about-hero__kicker {
  margin: 0;
  font: 700 12px/1.2 var(--font-mono);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .about-hero__title {
  margin: 0;
  max-width: 18ch;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 60ch;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 8px;
  background: repeating-linear-gradient(115deg, var(--cyan) 0 16px, transparent 16px 34px);
  opacity: 0.42;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 6px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 12px 14px;
  background: rgba(10, 13, 16, 0.78);
}

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

.page-about .about-stat__cap {
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 通用区块 ---------- */
.page-about .about-sec {
  padding: clamp(28px, 4vw, 48px) 0;
}

.page-about .about-sec-head {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: clamp(16px, 2.4vw, 26px);
}

.page-about .about-sec-head h2,
.page-about .about-next h2 {
  margin: 0;
}

.page-about .about-cols {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap);
  align-items: start;
}

.page-about .about-inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-dim);
}

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

/* ---------- 起点叙事 ---------- */
.page-about .about-origin__text h2 {
  margin: 0 0 14px;
}

.page-about .about-origin__text p {
  margin: 0 0 14px;
}

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

.page-about .about-origin__aside {
  position: relative;
  padding: 22px 18px 18px;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-facts {
  margin: 10px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-facts__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
}

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

.page-about .about-facts__key {
  font-size: 13px;
  color: var(--muted);
}

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

.page-about .about-band {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px 24px;
  margin-top: clamp(22px, 3vw, 34px);
  padding: 12px 16px;
  border-left: 3px solid var(--cyan);
  background: linear-gradient(93deg, var(--glass), transparent 72%);
  transform: skewY(-1.2deg);
}

.page-about .about-band > * {
  transform: skewY(1.2deg);
}

.page-about .about-band__note {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

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

/* ---------- 口径原则 ---------- */
.page-about .about-principles__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap);
}

.page-about .about-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 22px 18px 34px;
  border: 1px solid var(--line);
  background: var(--panel);
  clip-path: polygon(var(--ab-cut) 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%, 0 var(--ab-cut));
}

.page-about .about-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 56px;
  height: 3px;
  background: var(--cyan);
}

.page-about .about-card::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 74px;
  height: 22px;
  background: repeating-linear-gradient(115deg, var(--cyan-dim) 0 6px, transparent 6px 13px);
  opacity: 0.75;
}

.page-about .about-card__title {
  margin: 0;
  font: 700 20px/1.25 var(--font-display);
  letter-spacing: -0.01em;
  color: var(--text);
}

.page-about .about-card .body-text {
  margin: 0;
  font-size: 15px;
}

.page-about .about-card .expandable__trigger {
  align-self: flex-start;
}

.page-about .about-example {
  margin: 0;
  padding: 12px 14px;
  border-left: 2px solid var(--cyan-dim);
  background: var(--glass);
  font-size: 14px;
  line-height: 1.7;
  color: var(--text);
}

/* ---------- 团队分工 ---------- */
.page-about .about-bar {
  display: flex;
  height: 36px;
  overflow: hidden;
  border: 1px solid var(--line);
}

.page-about .about-bar__seg {
  display: flex;
  align-items: center;
  justify-content: center;
  font: 700 13px/1 var(--font-mono);
  color: var(--ink);
}

.page-about .about-bar__seg--a {
  flex: 9;
  background: var(--ab-seg-1);
}

.page-about .about-bar__seg--b {
  flex: 5;
  background: var(--ab-seg-2);
}

.page-about .about-bar__seg--c {
  flex: 4;
  background: var(--ab-seg-3);
  color: var(--text);
}

.page-about .about-bar__seg--d {
  flex: 3;
  background: var(--ab-seg-4);
  color: var(--text);
}

.page-about .about-team__list {
  margin: var(--gap) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .about-team__row {
  border: 1px solid var(--line);
  background: rgba(18, 23, 29, 0.72);
}

.page-about .about-team__trigger {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  width: 100%;
  padding: 14px 16px;
  border: 0;
  background: transparent;
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: background var(--t-fast) ease;
}

.page-about .about-team__trigger:hover {
  background: var(--glass);
}

.page-about .about-team__trigger:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: -2px;
}

.page-about .about-team__name {
  font: 700 16px/1.3 var(--font-display);
  letter-spacing: 0.02em;
}

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

.page-about .about-team__duty {
  flex: 1 1 100%;
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-team__facts {
  margin: 0;
  padding: 0 16px 16px 34px;
  list-style: square;
}

.page-about .about-team__facts li {
  margin: 7px 0;
  font-size: 14px;
  line-height: 1.65;
  color: var(--text);
}

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

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  clip-path: polygon(var(--ab-cut) 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%, 0 var(--ab-cut));
}

.page-about .about-team__figure .caption {
  margin-top: 12px;
}

/* ---------- 版本时间线 ---------- */
.page-about .about-ruler {
  display: none;
  width: 100%;
  height: auto;
}

.page-about .about-version__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap);
  margin-top: var(--gap);
}

.page-about .about-vercard {
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-vercard__trigger {
  display: flex;
  align-items: baseline;
  gap: 12px;
  width: 100%;
  padding: 14px 16px;
  border: 0;
  background: transparent;
  color: var(--text);
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: background var(--t-fast) ease;
}

.page-about .about-vercard__trigger:hover {
  background: var(--glass);
}

.page-about .about-vercard__trigger:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: -2px;
}

.page-about .about-vercard__tag {
  font-size: 13px;
  color: var(--cyan);
}

.page-about .about-vercard__name {
  font: 700 17px/1.3 var(--font-display);
  letter-spacing: 0.02em;
}

.page-about .about-vercard__body {
  margin: 0;
  padding: 14px 16px;
  border-top: 1px dashed var(--line);
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 质量与校验 ---------- */
.page-about .about-quality {
  position: relative;
  overflow: hidden;
  margin: clamp(20px, 3vw, 34px) 0;
  padding: clamp(30px, 4.4vw, 60px) clamp(18px, 3vw, 44px);
  border: 1px solid var(--line);
  background: var(--panel);
  clip-path: polygon(var(--ab-cut) 0, 100% 0, 100% calc(100% - var(--ab-cut)), calc(100% - var(--ab-cut)) 100%, 0 100%, 0 var(--ab-cut));
}

.page-about .about-quality__bg {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.20;
}

.page-about .about-quality__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-quality__inner h2 {
  margin: 0 0 12px;
}

.page-about .about-quality__text {
  margin: 0;
  max-width: 62ch;
}

.page-about .about-quality__metrics {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--gap);
  margin-top: clamp(18px, 2.6vw, 28px);
}

.page-about .about-metric {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-top: 14px;
  border-top: 2px solid var(--line);
}

.page-about .about-metric__num {
  color: var(--text);
}

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

.page-about .about-metric__cap {
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* ---------- 协作 ---------- */
.page-about .about-coop__text h2 {
  margin: 0 0 14px;
}

.page-about .about-coop__text p {
  margin: 0 0 14px;
}

.page-about .about-linkline {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .about-coop__aside {
  display: flex;
}

.page-about .about-coop__note {
  margin: 0;
  padding: 16px 18px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text);
}

/* ---------- 字段说明 ---------- */
.page-about .about-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--line);
  background: var(--line);
}

.page-about .about-fields__item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 4px 16px;
  padding: 14px 16px;
  background: rgba(10, 13, 16, 0.76);
}

.page-about .about-fields__name {
  font: 700 15px/1.4 var(--font-display);
  letter-spacing: 0.02em;
  color: var(--text);
}

.page-about .about-fields__read {
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-fields__note {
  margin: 16px 0 0;
}

/* ---------- 后续入口 ---------- */
.page-about .about-next__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-next__link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  background: rgba(18, 23, 29, 0.72);
  color: var(--text);
  text-decoration: none;
  transition: border-color var(--t-fast) ease, background var(--t-fast) ease;
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--cyan-dim);
  background: var(--glass);
}

.page-about .about-next__label {
  font: 700 16px/1.3 var(--font-display);
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.page-about .about-next__desc {
  font-size: 14px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__inner {
    padding: 34px 32px 52px;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-fields {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 780px) {
  .page-about .about-principles__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-ruler {
    display: block;
    margin-bottom: 4px;
  }

  .page-about .about-version__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-quality__metrics {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-cols {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: calc(var(--gap) * 1.4);
  }

  .page-about .about-cols--flip {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  }

  .page-about .about-hero__inner {
    padding: 44px 44px 62px;
    max-width: 1080px;
  }

  .page-about .about-origin__aside {
    margin-top: 8px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-next__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}