/* ===== 品牌概况页 · page-about ===== */

.page-about {
  --about-rule: 1px solid var(--orbit);
  --about-pad: clamp(44px, 6vw, 84px);
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  padding-top: clamp(16px, 2.4vw, 26px);
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead {
  padding-top: clamp(20px, 3vw, 34px);
}

.page-about .about-masthead__grid {
  display: grid;
  gap: 30px;
  padding-bottom: clamp(26px, 4vw, 46px);
}

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

.page-about .about-masthead h1 {
  margin: 14px 0 0;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(27px, 4.4vw, 44px);
  line-height: 1.2;
  letter-spacing: -0.012em;
  color: var(--paper);
  max-width: 19ch;
}

.page-about .about-masthead .lede {
  margin: 18px 0 0;
  max-width: 42ch;
  color: var(--mist);
  font-size: var(--fs-body);
  line-height: 1.85;
}

@media (min-width: 900px) {
  .page-about .about-masthead__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: end;
  }

  .page-about .about-masthead__main {
    padding-left: 24px;
    border-left: 2px solid var(--violet);
  }
}

/* ---------- 关键数字 ---------- */
.page-about .about-keyline {
  border-top: var(--about-rule);
}

.page-about .about-keyline__row {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: var(--about-rule);
}

.page-about .about-keyline__num {
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--cyan);
  letter-spacing: -0.01em;
}

.page-about .about-keyline__label {
  font-size: var(--fs-tiny);
  line-height: 1.65;
  color: var(--mist);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  padding: 16px 0 clamp(18px, 3vw, 28px);
}

.page-about .about-index__link {
  font-family: var(--font-mono);
  font-size: var(--fs-tiny);
  letter-spacing: 0.03em;
  color: var(--mist);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
  outline: none;
}

.page-about .about-index__link:focus-visible {
  box-shadow: 0 0 0 2px var(--cyan);
}

.page-about .about-index__link[aria-current] {
  color: var(--violet);
  border-bottom-color: var(--violet);
}

/* ---------- 通用区块 ---------- */
.page-about .about-section {
  padding-top: var(--about-pad);
  padding-bottom: var(--about-pad);
  border-top: var(--about-rule);
}

.page-about .about-section__grid {
  display: grid;
  gap: 26px;
}

@media (min-width: 900px) {
  .page-about .about-section__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(34px, 5vw, 68px);
  }
}

.page-about .about-section h2 {
  margin: 12px 0 0;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: clamp(23px, 3vw, 34px);
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: 24ch;
}

.page-about .about-section .prose {
  margin-top: 18px;
  color: var(--mist);
  font-size: var(--fs-body);
  line-height: 1.8;
}

.page-about .about-section .prose p {
  margin: 0;
  max-width: 36em;
}

.page-about .about-section .prose p + p {
  margin-top: 1em;
}

.page-about .about-section .prose a {
  color: var(--cyan);
}

.page-about .about-section__side {
  align-self: start;
}

@media (min-width: 900px) {
  .page-about .about-section__side {
    padding-top: 44px;
  }
}

/* ---------- 三个价值点 ---------- */
.page-about .about-values {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
}

.page-about .about-values__item {
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr);
  gap: 16px;
  padding: 18px 0;
  border-top: var(--about-rule);
  transition: background-color var(--dur) var(--ease);
}

.page-about .about-values__item:last-child {
  border-bottom: var(--about-rule);
}

.page-about .about-values__num {
  padding-top: 4px;
  font-size: var(--fs-tiny);
  color: var(--violet);
  letter-spacing: 0.08em;
}

.page-about .about-values__title {
  margin: 0;
  font-size: var(--fs-body);
  font-weight: 700;
  color: var(--paper);
  letter-spacing: 0.01em;
}

.page-about .about-values__desc {
  margin: 7px 0 0;
  font-size: var(--fs-aux);
  line-height: 1.75;
  color: var(--mist);
  max-width: 34em;
}

@media (hover: hover) {
  .page-about .about-values__item:hover .about-values__title {
    color: var(--cyan);
  }
}

/* ---------- 版本阶段 ---------- */
.page-about .about-phases__head {
  max-width: 46em;
}

.page-about .about-phases__lead {
  margin: 16px 0 0;
  font-size: var(--fs-aux);
  line-height: 1.8;
  color: var(--mist);
  max-width: 34em;
}

.page-about .about-phases__figure {
  margin: clamp(26px, 4vw, 44px) 0 clamp(30px, 4.5vw, 52px);
}

.page-about .about-rail {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 28px;
}

.page-about .about-rail::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 6px;
  bottom: 18px;
  width: 1px;
  background: var(--orbit);
}

.page-about .about-rail__item {
  position: relative;
  padding-bottom: 30px;
}

.page-about .about-rail__item:last-child {
  padding-bottom: 0;
}

.page-about .about-rail__node {
  position: absolute;
  left: -28px;
  top: 5px;
  width: 9px;
  height: 9px;
  transform: rotate(45deg);
  background: var(--cyan);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-rail__phase {
  margin: 0;
  font-size: var(--fs-tiny);
  letter-spacing: 0.12em;
  color: var(--mist-soft);
}

.page-about .about-rail__title {
  margin: 8px 0 0;
  font-family: var(--font-title);
  font-weight: 800;
  font-size: var(--fs-sm);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-rail__desc {
  margin: 10px 0 0;
  font-size: var(--fs-aux);
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-rail__detail {
  margin: 12px 0 0;
  padding-top: 10px;
  border-top: 1px dashed var(--orbit);
  font-size: var(--fs-tiny);
  line-height: 1.7;
  color: var(--mist-soft);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-rail__item--now .about-rail__node {
  background: var(--gold);
}

.page-about .about-rail__item--now .about-rail__phase {
  color: var(--gold);
}

.page-about .about-rail__item--now .about-rail__title {
  color: var(--gold);
}

@media (hover: hover) {
  .page-about .about-rail__item:hover .about-rail__detail {
    color: var(--cyan);
    border-top-color: var(--cyan);
  }

  .page-about .about-rail__item:hover .about-rail__node {
    background: var(--gold);
    box-shadow: 0 0 0 5px rgba(138, 92, 246, 0.22);
  }
}

.page-about .about-phases__more {
  margin: clamp(26px, 4vw, 40px) 0 0;
  padding-top: 18px;
  border-top: var(--about-rule);
  font-size: var(--fs-aux);
  line-height: 1.8;
  color: var(--mist);
}

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

@media (min-width: 900px) {
  .page-about .about-rail {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0 20px;
    padding-left: 0;
  }

  .page-about .about-rail::before {
    left: 0;
    right: 0;
    top: 5px;
    bottom: auto;
    width: auto;
    height: 1px;
  }

  .page-about .about-rail__item {
    padding: 30px 0 0;
  }

  .page-about .about-rail__item:last-child {
    padding-top: 30px;
  }

  .page-about .about-rail__node {
    left: 0;
    top: 1px;
  }

  .page-about .about-rail__detail {
    font-size: 12px;
  }
}

/* ---------- 维护团队 ---------- */
.page-about .about-team__grid {
  align-items: start;
}

.page-about .about-crews {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-crews__item {
  display: grid;
  gap: 5px 20px;
  padding: 16px 0;
  border-top: var(--about-rule);
}

.page-about .about-crews__item:last-child {
  border-bottom: var(--about-rule);
}

.page-about .about-crews__name {
  font-family: var(--font-serif);
  font-size: var(--fs-body);
  font-weight: 600;
  color: var(--cyan);
  letter-spacing: 0.02em;
}

.page-about .about-crews__desc {
  margin: 0;
  font-size: var(--fs-aux);
  line-height: 1.75;
  color: var(--mist);
  max-width: 38em;
}

@media (min-width: 640px) {
  .page-about .about-crews__item {
    grid-template-columns: 118px minmax(0, 1fr);
    align-items: baseline;
  }
}

.page-about .about-team__aside {
  display: grid;
  gap: 20px;
  align-self: start;
}

@media (min-width: 900px) {
  .page-about .about-team__aside {
    padding-top: 40px;
  }
}

/* ---------- 服务覆盖 ---------- */
.page-about .about-coverage__grid {
  display: grid;
  gap: 30px;
}

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

@media (min-width: 900px) {
  .page-about .about-coverage__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: clamp(36px, 5vw, 72px);
    align-items: start;
  }
}

.page-about .about-stats {
  margin: 28px 0 0;
  border-top: var(--about-rule);
}

.page-about .about-stats__item {
  display: grid;
  grid-template-columns: 108px minmax(0, 1fr);
  gap: 6px 18px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: var(--about-rule);
}

.page-about .about-stats__value {
  font-size: var(--fs-md);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--cyan);
  transition: color var(--dur) var(--ease);
}

.page-about .about-stats__label {
  font-size: var(--fs-tiny);
  line-height: 1.7;
  color: var(--mist);
}

@media (hover: hover) {
  .page-about .about-stats__item:hover .about-stats__value {
    color: var(--gold);
  }
}

/* ---------- 官方信息 ---------- */
.page-about .about-official__grid {
  display: grid;
  gap: 30px;
}

@media (min-width: 900px) {
  .page-about .about-official__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(36px, 5vw, 72px);
    align-items: start;
  }
}

.page-about .about-official__lead p {
  margin: 16px 0 0;
  max-width: 34em;
  font-size: var(--fs-aux);
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-official__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-official__list {
  margin: 0;
  border-top: var(--about-rule);
}

.page-about .about-official__row {
  display: grid;
  gap: 4px;
  padding: 15px 0;
  border-bottom: var(--about-rule);
}

.page-about .about-official__term {
  font-family: var(--font-mono);
  font-size: var(--fs-tiny);
  letter-spacing: 0.1em;
  color: var(--mist-soft);
}

.page-about .about-official__value {
  margin: 0;
  font-size: var(--fs-body);
  line-height: 1.7;
  color: var(--paper);
}

.page-about .about-official__row:nth-child(1) .about-official__value {
  color: var(--gold);
}

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

@media (min-width: 720px) {
  .page-about .about-official__row {
    grid-template-columns: 140px minmax(0, 1fr);
    gap: 18px;
    align-items: baseline;
  }
}

/* ---------- 窄屏保护 ---------- */
@media (max-width: 639px) {
  .page-about .about-keyline__row {
    grid-template-columns: 68px minmax(0, 1fr);
  }

  .page-about .about-stats__item {
    grid-template-columns: 92px minmax(0, 1fr);
  }

  .page-about .about-section h2,
  .page-about .about-masthead h1 {
    max-width: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__node,
  .page-about .about-rail__detail,
  .page-about .about-stats__value,
  .page-about .about-index__link,
  .page-about .about-values__item {
    transition: none;
  }

  .page-about .about-rail__item:hover .about-rail__node {
    box-shadow: none;
  }
}