.page-about {
  background: var(--paper);
  color: var(--ink);
}

.page-about .breadcrumb {
  margin: 22px 0 18px;
}

/* ---------- 框景首屏 ---------- */

.page-about .about-hero {
  padding: 0 0 12px;
}

.page-about .about-hero__inner {
  position: relative;
  border: 2px solid var(--navy);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #FBF7EC 0%, #F3EDDF 100%);
  padding: 26px 20px 30px;
  box-shadow: var(--shadow-soft);
}

.page-about .about-hero__inner::after {
  content: "";
  position: absolute;
  top: -2px;
  right: 20px;
  width: 68px;
  height: 8px;
  background: var(--orange);
}

.page-about .about-hero__rule {
  display: block;
  height: 9px;
  margin-bottom: 20px;
  background: repeating-linear-gradient(90deg, var(--navy) 0 2px, transparent 2px 14px);
  opacity: .45;
}

.page-about .about-hero__inner .eyebrow {
  margin: 0 0 12px;
}

.page-about .about-hero__inner .display {
  margin: 0 0 16px;
  max-width: 20em;
}

.page-about .about-hero__inner .lead {
  max-width: var(--measure);
  margin: 0;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 18px;
  margin: 30px 0 0;
  padding-top: 24px;
  border-top: 1px solid rgba(11, 46, 79, .18);
}

.page-about .about-fact dt {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--grey);
}

.page-about .about-fact dd {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--navy);
}

.page-about .about-fact dd small {
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 400;
  color: var(--grey);
}

/* ---------- 三次改版：左窄右宽时间轴 ---------- */

.page-about .about-chrono {
  margin-top: 72px;
}

.page-about .about-chrono > .h2,
.page-about .about-teams > .h2,
.page-about .about-users > .h2,
.page-about .about-habits > .h2 {
  margin: 0 0 10px;
}

.page-about .about-chrono__intro {
  max-width: var(--measure);
  margin: 0 0 22px;
  font-size: 16px;
  line-height: 1.8;
  color: #3A4753;
}

.page-about .about-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0 0 34px;
}

.page-about .about-jump a {
  display: inline-block;
  padding: 7px 13px;
  border: 1px solid rgba(11, 46, 79, .26);
  border-radius: var(--radius);
  background: #FBF7EC;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--navy);
  text-decoration: none;
  transition: background-color .2s var(--ease), border-color .2s var(--ease), color .2s var(--ease);
}

.page-about .about-jump a:hover,
.page-about .about-jump a:focus-visible {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink);
}

.page-about .about-chrono__list {
  display: grid;
  gap: 0;
}

.page-about .about-chrono__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  padding: 28px 0 30px;
  border-top: 1px solid rgba(11, 46, 79, .16);
}

.page-about .about-node {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.page-about .about-node__bar {
  width: 30px;
  height: 6px;
  background: var(--orange);
}

.page-about .about-node__year {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--navy);
}

.page-about .about-node__label {
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--grey);
}

.page-about .about-chrono__body .h3 {
  margin: 0 0 12px;
}

.page-about .about-chrono__body .body {
  max-width: var(--measure);
  margin: 0 0 12px;
}

.page-about .about-chrono__body .body:last-child {
  margin-bottom: 0;
}

.page-about .about-chrono__wide {
  margin: 30px 0 4px;
}

/* ---------- 三组分工 ---------- */

.page-about .about-teams {
  margin-top: 80px;
}

.page-about .about-teams__media {
  margin: 22px 0 30px;
}

.page-about .about-teams__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.page-about .about-team {
  padding: 22px 20px 18px;
  background: var(--card);
  border-top: 5px solid var(--navy);
  border-radius: var(--radius);
}

.page-about .about-team--column {
  border-top-color: var(--orange);
}

.page-about .about-team--data {
  border-top-color: var(--teal);
}

.page-about .about-team__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

.page-about .about-team__name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-team__count {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--navy);
}

.page-about .about-team__desc {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: #33404C;
}

.page-about .about-team__more {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed rgba(11, 46, 79, .3);
}

.page-about .about-team__more summary {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  list-style: none;
  font-size: 14px;
  font-weight: 700;
  color: var(--navy);
}

.page-about .about-team__more summary::-webkit-details-marker {
  display: none;
}

.page-about .about-team__more summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-team__more[open] summary::after {
  content: "–";
}

.page-about .about-team__more p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: #3A4753;
}

/* ---------- 档案流程：深蓝反色区 ---------- */

.page-about .about-archive {
  position: relative;
  margin-top: 84px;
  padding: 52px 0 58px;
  background: var(--navy);
  color: var(--paper);
}

.page-about .about-archive::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 8px;
  background: repeating-linear-gradient(90deg, var(--orange) 0 14px, transparent 14px 28px);
}

.page-about .about-archive .h2 {
  margin: 0 0 12px;
  color: #FFFFFF;
}

.page-about .about-archive .about-chrono__intro {
  color: rgba(245, 240, 228, .78);
}

.page-about .about-flow {
  display: grid;
  gap: 0;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-flow__item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 16px;
  padding: 20px 0;
  border-bottom: 1px solid rgba(245, 240, 228, .18);
}

.page-about .about-flow__num {
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--orange);
}

.page-about .about-flow__title {
  margin: 0 0 7px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -.01em;
  color: #FFFFFF;
}

.page-about .about-flow__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(245, 240, 228, .82);
}

.page-about .about-archive__note {
  max-width: var(--measure);
  margin: 28px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(245, 240, 228, .82);
}

.page-about .about-archive__note a {
  color: var(--orange-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 使用场景 ---------- */

.page-about .about-users {
  margin-top: 84px;
}

.page-about .about-users__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  margin-top: 24px;
}

.page-about .about-users__list {
  display: grid;
  gap: 18px;
}

.page-about .about-user {
  padding: 2px 0 2px 16px;
  border-left: 3px solid var(--orange-soft);
}

.page-about .about-user .h3 {
  margin: 0 0 6px;
  font-size: 16px;
}

.page-about .about-user p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: #3A4753;
}

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

/* ---------- 编辑习惯 ---------- */

.page-about .about-habits {
  margin-top: 84px;
}

.page-about .about-habits__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  margin-top: 24px;
}

.page-about .about-habits__list .h3 {
  margin: 0 0 8px;
  font-size: 17px;
}

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

/* ---------- 运营主体与联系 ---------- */

.page-about .about-contact {
  margin-top: 88px;
  padding: 50px 0 60px;
  background: var(--navy-2);
  color: var(--paper);
}

.page-about .about-contact .h2 {
  margin: 0 0 12px;
  color: #FFFFFF;
}

.page-about .about-contact .body {
  max-width: var(--measure);
  margin: 0;
  color: rgba(245, 240, 228, .84);
}

.page-about .about-contact__list {
  display: grid;
  gap: 0;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-contact__item {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(245, 240, 228, .18);
}

.page-about .about-contact__key {
  flex: 0 0 66px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--orange-soft);
}

.page-about .about-contact__val {
  font-size: 15.5px;
  line-height: 1.6;
  color: #FFFFFF;
  overflow-wrap: anywhere;
}

.page-about .about-contact .copy-btn {
  border: 1px solid rgba(245, 240, 228, .42);
  border-radius: var(--radius);
  background: transparent;
  color: var(--paper);
  font-size: 12.5px;
  padding: 5px 11px;
  cursor: pointer;
}

.page-about .about-contact .copy-btn:hover,
.page-about .about-contact .copy-btn:focus-visible {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink);
}

.page-about .about-contact .copy-btn[data-copied] {
  background: var(--teal);
  border-color: var(--teal);
  color: #FFFFFF;
}

.page-about .about-contact__note {
  max-width: var(--measure);
  margin: 24px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(245, 240, 228, .78);
}

.page-about .about-contact__note a {
  color: var(--orange-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-contact__links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 30px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 760px) {
  .page-about .about-hero__inner {
    padding: 36px 40px 40px;
  }

  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 22px 24px;
  }

  .page-about .about-fact dd {
    font-size: 32px;
  }

  .page-about .about-flow__item {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 22px;
    padding: 22px 0;
  }
}

@media (min-width: 880px) {
  .page-about .about-teams__grid {
    grid-template-columns: 5fr 4fr 3fr;
    gap: 22px;
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-chrono__row {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 46px;
    padding: 40px 0 44px;
  }

  .page-about .about-chrono__wide {
    margin: 42px 0 10px;
  }

  .page-about .about-users__grid {
    grid-template-columns: 1.15fr .85fr;
    gap: 40px;
    align-items: start;
  }

  .page-about .about-users__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px 26px;
  }

  .page-about .about-habits__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px 32px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-chrono {
    margin-top: 88px;
  }

  .page-about .about-hero__inner .display {
    max-width: 18em;
  }
}

@media (max-width: 480px) {
  .page-about .about-node__year {
    font-size: 24px;
  }

  .page-about .about-fact dd {
    font-size: 24px;
  }

  .page-about .about-contact__key {
    flex-basis: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition: none !important;
    animation: none !important;
    scroll-behavior: auto !important;
  }
}