/* ===== /mission/ 品牌与理念 ===== */
.page-about{
  --about-rule: rgba(43, 42, 38, .13);
  --about-rule-soft: rgba(43, 42, 38, .08);
  background: var(--paper);
  color: var(--char);
  font-family: var(--font-sans);
}

.page-about .about-wrap{
  max-width: var(--shell);
  margin: 0 auto;
  padding: 16px 18px 56px;
}

.page-about .about-grid{
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
  align-items: start;
  margin-top: 14px;
}

.page-about .about-main{
  min-width: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-open{
  padding-bottom: 6px;
}

.page-about .about-kicker{
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--copper);
  text-transform: uppercase;
}

.page-about .about-h1{
  margin: 0 0 20px;
  max-width: 17em;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(30px, 5.2vw, 54px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-lead{
  max-width: 34em;
  margin: 0;
  padding-left: 16px;
  border-left: 3px solid var(--copper);
  font-size: 17px;
  line-height: 1.9;
  color: var(--char);
}

.page-about .about-open__bar{
  display: flex;
  align-items: center;
  gap: 9px;
  margin-top: 24px;
  padding-top: 14px;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-open__status{
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--ash);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec{
  margin-top: 48px;
  padding-top: 38px;
  border-top: 1px solid var(--about-rule);
}

.page-about .lg-section__num{
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--copper);
}

.page-about .lg-section__title{
  font-family: var(--font-serif);
  font-size: clamp(23px, 3.4vw, 34px);
  line-height: 1.3;
  color: var(--ink);
}

.page-about .lg-section__desc{
  max-width: 36em;
  color: var(--ash);
  font-size: 14.5px;
  line-height: 1.85;
}

.page-about .about-copy{
  max-width: 34em;
  margin-top: 20px;
}

.page-about .about-copy p{
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.9;
  color: var(--char);
}

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

.page-about .about-sec > .lg-note{
  max-width: 34em;
  margin-top: 22px;
}

/* ---------- 三条主线 ---------- */
.page-about .about-paths{
  position: relative;
  margin-top: 26px;
  padding-left: 30px;
}

.page-about .about-paths::before{
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--copper) 0%, rgba(192, 138, 62, .18) 100%);
}

.page-about .about-path{
  position: relative;
  padding-bottom: 26px;
}

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

.page-about .about-path::before{
  content: "";
  position: absolute;
  left: -25px;
  top: 7px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--copper);
  box-sizing: border-box;
}

.page-about .about-path__idx{
  display: block;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--copper);
}

.page-about .about-path__title{
  margin: 6px 0 8px;
  font-family: var(--font-serif);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--ink);
}

.page-about .about-path__text{
  max-width: 36em;
  margin: 0 0 10px;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--char);
}

.page-about .about-path__when{
  display: inline-block;
  margin: 0;
  padding: 4px 10px;
  border-left: 2px solid var(--copper-lt);
  background: rgba(224, 178, 106, .16);
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-2);
}

.page-about .about-paths__cta{
  margin: 24px 0 0;
}

/* ---------- 团队技能树 ---------- */
.page-about .about-tree{
  margin-top: 26px;
}

.page-about .about-tree__root{
  display: inline-flex;
  align-items: baseline;
  gap: 9px;
  padding: 12px 20px;
  background: var(--ink);
  color: var(--paper);
  border-radius: var(--radius);
  box-shadow: inset 0 -2px 0 var(--copper);
}

.page-about .about-tree__rootnum{
  font-size: 26px;
  line-height: 1;
  color: var(--copper-lt);
}

.page-about .about-tree__roottext{
  font-size: 15px;
  letter-spacing: .02em;
}

.page-about .about-tree__groups{
  position: relative;
  list-style: none;
  margin: 0;
  padding: 20px 0 0 28px;
}

.page-about .about-tree__groups::before{
  content: "";
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 30px;
  width: 2px;
  background: var(--copper-lt);
}

.page-about .about-tree__group{
  position: relative;
  padding: 0 0 22px;
  outline: none;
}

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

.page-about .about-tree__group::before{
  content: "";
  position: absolute;
  left: -20px;
  top: 11px;
  width: 16px;
  height: 2px;
  background: var(--copper-lt);
}

.page-about .about-tree__gtitle{
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
  transition: color .16s ease;
}

.page-about .about-tree__gtext{
  max-width: 36em;
  margin: 0 0 8px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--char);
}

.page-about .about-tree__gtag{
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--ash);
  transition: color .16s ease;
}

.page-about .about-tree__gtag::before{
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--copper);
  transition: box-shadow .16s ease;
}

.page-about .about-tree__group:hover .about-tree__gtitle,
.page-about .about-tree__group:focus-visible .about-tree__gtitle,
.page-about .about-tree__group:focus-within .about-tree__gtitle{
  color: var(--pine);
}

.page-about .about-tree__group:hover .about-tree__gtag,
.page-about .about-tree__group:focus-visible .about-tree__gtag,
.page-about .about-tree__group:focus-within .about-tree__gtag{
  color: var(--ink-2);
}

.page-about .about-tree__group:hover .about-tree__gtag::before,
.page-about .about-tree__group:focus-visible .about-tree__gtag::before,
.page-about .about-tree__group:focus-within .about-tree__gtag::before{
  box-shadow: 0 0 0 4px rgba(192, 138, 62, .22);
}

/* ---------- 时间线 ---------- */
.page-about .about-history{
  margin-top: 26px;
}

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

.page-about .about-tl{
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 0 18px;
  outline: none;
}

.page-about .about-tl__side{
  position: relative;
  border-right: 2px solid var(--copper-lt);
  padding-right: 12px;
  padding-bottom: 28px;
}

.page-about .about-tl__side::after{
  content: "";
  position: absolute;
  right: -6px;
  top: 6px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--copper);
}

.page-about .about-tl__year{
  display: block;
  font-size: 15px;
  line-height: 1.4;
  letter-spacing: .04em;
  color: var(--ink-2);
}

.page-about .about-tl__body{
  padding-bottom: 28px;
}

.page-about .about-tl__title{
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .about-tl__text{
  max-width: 34em;
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--char);
}

.page-about .about-tl__more{
  max-width: 34em;
  margin: 10px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--about-rule);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ash);
  max-height: none;
  opacity: 1;
  overflow: hidden;
  transition: max-height .28s ease, opacity .2s ease, margin-top .2s ease;
}

/* ---------- 覆盖信息带 ---------- */
.page-about .about-reach{
  margin-top: 48px;
}

.page-about .about-reach__panel{
  padding: 26px 20px 24px;
  background: var(--mist);
  border-left: 3px solid var(--ink);
  border-radius: var(--radius);
}

.page-about .about-reach__kicker{
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--ink-2);
}

.page-about .about-reach__title{
  margin: 0 0 12px;
  font-family: var(--font-serif);
  font-size: clamp(22px, 3.2vw, 32px);
  line-height: 1.3;
  color: var(--ink);
}

.page-about .about-reach__lede{
  max-width: 40em;
  margin: 0;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--char);
}

.page-about .about-stats{
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 16px;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-stat__fig{
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 3px;
}

.page-about .about-stat__num{
  font-size: 30px;
  line-height: 1.05;
  letter-spacing: -.01em;
  color: var(--ink);
  border-bottom: 1px solid var(--copper);
  padding-bottom: 4px;
}

.page-about .about-stat__unit{
  font-size: 13px;
  color: var(--ink-2);
}

.page-about .about-stat__label{
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--char);
}

/* ---------- 编号与校对 ---------- */
.page-about .about-coderule{
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 24px;
  padding: 20px;
  background: var(--card);
  border-radius: var(--radius);
  border-left: 3px solid var(--copper);
}

.page-about .about-coderule__sample{
  font-size: 30px;
  line-height: 1;
  letter-spacing: .04em;
  color: var(--ink);
}

.page-about .about-coderule__desc{
  margin: 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--char);
}

.page-about .about-checks{
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .about-check{
  position: relative;
  padding-left: 18px;
}

.page-about .about-check::before{
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 8px;
  height: 2px;
  background: var(--copper);
}

.page-about .about-check__title{
  margin: 0 0 7px;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .about-check__text{
  max-width: 36em;
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--char);
}

/* ---------- 认可 ---------- */
.page-about .about-actions{
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 图片 ---------- */
.page-about .about-figure{
  margin: 26px 0 0;
}

.page-about .about-figure--stack{
  margin-top: 6px;
}

/* ---------- 右侧书签 ---------- */
.page-about .about-bookmark{
  display: none;
}

/* ---------- 窄屏微调 ---------- */
@media (max-width: 519px){
  .page-about .about-tl{
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 0 14px;
  }

  .page-about .about-tl__year{
    font-size: 13.5px;
  }

  .page-about .about-stat__num{
    font-size: 26px;
  }
}

@media (min-width: 640px){
  .page-about .about-checks{
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px 28px;
  }

  .page-about .about-checks .about-check:first-child{
    grid-column: 1 / -1;
  }

  .page-about .about-stats{
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  }

  .page-about .about-coderule{
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 20px;
  }
}

@media (min-width: 900px){
  .page-about .about-wrap{
    padding: 26px 32px 72px;
  }

  .page-about .about-lead{
    font-size: 18px;
  }

  .page-about .about-path{
    padding-bottom: 30px;
  }

  .page-about .about-tl__title{
    font-size: 20px;
  }

  .page-about .about-reach__panel{
    padding: 34px 34px 30px;
  }

  .page-about .about-coderule{
    padding: 26px 28px;
  }
}

@media (min-width: 1040px){
  .page-about .about-grid{
    grid-template-columns: minmax(0, 1fr) 216px;
    gap: 52px;
  }

  .page-about .about-bookmark{
    display: block;
    position: sticky;
    top: 112px;
    padding-left: 16px;
    border-left: 2px solid var(--copper-lt);
  }

  .page-about .about-bookmark__title{
    margin: 0 0 12px;
    font-size: 11px;
    letter-spacing: .16em;
    color: var(--copper);
  }

  .page-about .about-bookmark__list{
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 11px;
    counter-reset: about-book;
  }

  .page-about .about-bookmark__list li{
    position: relative;
    padding-left: 20px;
  }

  .page-about .about-bookmark__list li::before{
    counter-increment: about-book;
    content: counter(about-book, decimal-leading-zero);
    position: absolute;
    left: 0;
    top: 2px;
    font-family: var(--font-mono);
    font-size: 10.5px;
    color: var(--copper);
  }

  .page-about .about-bookmark__link{
    display: block;
    font-size: 13px;
    line-height: 1.6;
    color: var(--char);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    padding-bottom: 2px;
    transition: color .16s ease, border-color .16s ease;
  }

  .page-about .about-bookmark__link:hover,
  .page-about .about-bookmark__link:focus-visible{
    color: var(--pine);
    border-bottom-color: var(--pine);
  }

  .page-about .about-figure--stack{
    margin-top: 4px;
  }
}

@media (min-width: 900px) and (hover: hover){
  .page-about .about-tl__more{
    max-height: 0;
    margin-top: 0;
    opacity: 0;
  }

  .page-about .about-tl:hover .about-tl__more,
  .page-about .about-tl:focus-within .about-tl__more{
    max-height: 220px;
    margin-top: 10px;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about .about-tl__more,
  .page-about .about-bookmark__link,
  .page-about .about-tree__gtitle,
  .page-about .about-tree__gtag{
    transition: none;
  }
}