.page-about {
  --ab-rule: var(--rule);
}

.page-about .about-crumbs {
  padding-top: 2rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(1.75rem, 4vw, 3rem) 0 clamp(2.5rem, 6vw, 4.25rem);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(2rem, 4vw, 3.25rem);
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
  }
}

.page-about .about-hero h1 {
  margin: 0.75rem 0 1.35rem;
  font-size: clamp(2.05rem, 5.2vw, 3.5rem);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.02em;
}

.page-about .about-hero .lede {
  max-width: 33em;
  font-size: clamp(1rem, 1.5vw, 1.12rem);
  line-height: 1.8;
}

.page-about .about-hero__facts {
  margin: 1.6rem 0 0;
  padding-top: 1rem;
  border-top: 1px solid var(--ab-rule);
  font-size: 0.8rem;
  letter-spacing: 0.05em;
  color: var(--graphite);
}

.page-about .about-hero__side {
  background: var(--teal);
  color: var(--paper);
  border-radius: var(--r-xl);
  padding: clamp(1.5rem, 3vw, 2.1rem);
}

.page-about .about-hero__sideTitle {
  margin: 0 0 1.15rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--focus);
}

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

.page-about .about-facts__item {
  display: grid;
  grid-template-columns: 2.1rem minmax(0, 1fr);
  gap: 0.6rem;
  padding: 0.95rem 0 0;
  margin-top: 0.95rem;
  border-top: 1px solid rgba(245, 241, 232, 0.2);
  font-size: 0.9rem;
  line-height: 1.7;
}

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

.page-about .about-facts__k {
  font-size: 0.76rem;
  color: var(--focus);
  padding-top: 0.25rem;
}

/* ---------- 章节索引 ---------- */
.page-about .about-map {
  border-top: 1px solid var(--ab-rule);
  border-bottom: 1px solid var(--ab-rule);
  padding: 1.15rem 0;
}

.page-about .about-map__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.75rem;
}

.page-about .about-map__link {
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.2rem 0;
  font-size: 0.9rem;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 160ms ease-out, border-color 160ms ease-out;
}

.page-about .about-map__link .mono {
  font-size: 0.74rem;
  color: var(--blue);
}

.page-about .about-map__link:hover,
.page-about .about-map__link:focus-visible {
  color: var(--blue-deep);
  border-bottom-color: var(--blue);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding: clamp(3rem, 7vw, 5.5rem) 0;
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .about-chapter:last-of-type {
  border-bottom: 0;
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(0.9rem, 2vw, 1.5rem);
  align-items: start;
  margin-bottom: clamp(1.5rem, 3vw, 2.25rem);
}

.page-about .about-chapter__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 700;
  line-height: 0.92;
  letter-spacing: -0.03em;
  color: var(--blue);
}

.page-about .about-chapter h2 {
  margin: 0;
  font-size: clamp(1.55rem, 3.4vw, 2.15rem);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.page-about .about-chapter__body {
  max-width: 34rem;
  font-size: 1.02rem;
  line-height: 1.82;
}

.page-about .about-chapter__body p {
  margin: 0 0 1.05rem;
}

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

.page-about .about-chapter--w2 .about-chapter__body {
  max-width: 41rem;
}

.page-about .about-chapter--w3 .about-chapter__body {
  max-width: 52rem;
}

.page-about .about-chapter--w4 .about-chapter__body {
  max-width: none;
}

.page-about .about-chapter__fig {
  margin: 0 0 clamp(2rem, 4vw, 3rem);
}

/* ---------- 图文分栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.75rem, 4vw, 3rem);
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 22rem);
    align-items: start;
  }
}

@media (min-width: 1120px) {
  .page-about .about-split__fig {
    margin-right: -56px;
  }
}

/* ---------- 媒体容器 ---------- */
.page-about .media__frame {
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--paper-2);
}

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

.page-about .media__caption {
  margin-top: 0.7rem;
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--graphite);
}

/* ---------- 旁注块 ---------- */
.page-about .about-note {
  margin-top: 1.9rem;
  padding: 0.3rem 0 0.3rem 1.15rem;
  border-left: 4px solid var(--teal);
  max-width: 48rem;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--graphite);
}

/* ---------- 版本线 ---------- */
.page-about .vline__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
}

.page-about .vline__item {
  position: relative;
  padding: 0 0 2.1rem 1.75rem;
  border-left: 2px solid var(--ab-rule);
  outline: none;
}

.page-about .vline__item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .vline__item:focus-visible {
  box-shadow: 0 0 0 3px var(--focus);
  border-radius: var(--r-md);
}

.page-about .vline__dot {
  position: absolute;
  left: -8px;
  top: 0.32rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 5px var(--paper);
  transition: transform 160ms ease-out;
}

.page-about .vline__item:hover .vline__dot,
.page-about .vline__item:focus-visible .vline__dot {
  transform: scale(1.3);
}

.page-about .vline__ver {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.45rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .vline__title {
  margin: 0.65rem 0 0.4rem;
  font-size: 1.05rem;
  font-weight: 800;
  line-height: 1.4;
}

.page-about .vline__desc {
  margin: 0;
  font-size: 0.91rem;
  line-height: 1.78;
  color: var(--graphite);
}

.page-about .vline__more {
  margin: 0.75rem 0 0;
  padding-left: 0.6rem;
  border-left: 2px solid var(--green);
  font-family: var(--font-mono);
  font-size: 0.73rem;
  letter-spacing: 0.03em;
  color: var(--green);
}

@media (min-width: 880px) {
  .page-about .vline__list {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0 1.5rem;
    border-top: 2px solid var(--ab-rule);
    padding-top: 0;
  }

  .page-about .vline__item {
    padding: 2.1rem 0 0;
    border-left: 0;
  }

  .page-about .vline__item:last-child {
    border-left: 0;
  }

  .page-about .vline__dot {
    left: 0;
    top: -8px;
  }
}

/* ---------- 职能分工 ---------- */
.page-about .roster {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--ab-rule);
}

.page-about .roster__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "name num"
    "track track"
    "duty duty";
  gap: 0.5rem 0.75rem;
  padding: 1rem 0.6rem 1.05rem;
  border-bottom: 1px solid var(--ab-rule);
  transition: background-color 160ms ease-out;
}

.page-about .roster__row:hover {
  background: rgba(31, 111, 235, 0.05);
}

.page-about .roster__name {
  grid-area: name;
  margin: 0;
  font-size: 1rem;
  font-weight: 800;
}

.page-about .roster__num {
  grid-area: num;
  margin: 0;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--blue);
}

.page-about .roster__track {
  grid-area: track;
  height: 9px;
  border-radius: var(--r-pill);
  background: var(--paper-2);
  overflow: hidden;
}

.page-about .roster__bar {
  display: block;
  height: 100%;
  border-radius: var(--r-pill);
  transition: width 220ms ease-out;
}

.page-about .roster__bar--research { width: 60%; background: var(--blue); }
.page-about .roster__bar--interaction { width: 100%; background: var(--teal); }
.page-about .roster__bar--brand { width: 78%; background: var(--indigo); }
.page-about .roster__bar--frontend { width: 56%; background: var(--wine); }
.page-about .roster__bar--content { width: 43%; background: var(--orange); }

.page-about .roster__duty {
  grid-area: duty;
  margin: 0;
  max-width: 46rem;
  font-size: 0.86rem;
  line-height: 1.72;
  color: var(--graphite);
}

/* ---------- 客户与合作伙伴 ---------- */
.page-about .cstats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 clamp(1.75rem, 4vw, 2.5rem);
  background: var(--ab-rule);
  border-radius: var(--r-lg);
  overflow: hidden;
}

@media (min-width: 720px) {
  .page-about .cstats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .cstats__cell {
  background: var(--paper-3);
  padding: 1.25rem 1.15rem;
}

.page-about .cstats__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3vw, 1.95rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--teal);
}

.page-about .cstats__label {
  display: block;
  margin-top: 0.4rem;
  font-size: 0.8rem;
  line-height: 1.6;
  color: var(--graphite);
}

/* ---------- 资质 ---------- */
.page-about .creds {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

@media (min-width: 760px) {
  .page-about .creds {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .creds__item {
  background: var(--paper-3);
  border-left: 4px solid var(--indigo);
  border-radius: var(--r-lg);
  padding: 1.25rem 1.35rem;
}

.page-about .creds__k {
  margin: 0;
  font-size: 0.98rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--indigo);
}

.page-about .creds__v {
  margin: 0.55rem 0 0;
  font-size: 0.9rem;
  line-height: 1.78;
}

/* ---------- 页尾引导 ---------- */
.page-about .about-next {
  margin-top: clamp(2.5rem, 6vw, 4rem);
  background: var(--teal);
  color: var(--paper);
  padding: clamp(2.25rem, 6vw, 3.75rem) 0;
}

.page-about .about-next__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}

@media (min-width: 860px) {
  .page-about .about-next__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    align-items: center;
  }
}

.page-about .about-next h2 {
  margin: 0 0 0.8rem;
  font-size: clamp(1.35rem, 2.8vw, 1.85rem);
  font-weight: 900;
  color: var(--paper);
}

.page-about .about-next p {
  margin: 0;
  max-width: 34rem;
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(245, 241, 232, 0.86);
}

.page-about .about-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-map__link,
  .page-about .roster__row,
  .page-about .roster__bar,
  .page-about .vline__dot {
    transition: none;
  }

  .page-about .vline__item:hover .vline__dot,
  .page-about .vline__item:focus-visible .vline__dot {
    transform: none;
  }
}