.page-about {
  --about-t1: #A8EFC9;
  --about-t2: #3DDC84;
  --about-t3: #12A85A;
  --about-t4: #1F2428;
  --about-rail-w: 208px;
  background: var(--mist);
}

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

.page-about .breadcrumbs {
  padding: 1.1rem 0 0.25rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--panel-2);
  color: var(--paper);
  padding: 2.75rem 0 4.5rem;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 38px), 0 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -18%;
  top: -45%;
  width: 62%;
  height: 190%;
  transform: rotate(-9deg);
  background: linear-gradient(170deg, rgba(61, 220, 132, 0.22), rgba(61, 220, 132, 0) 62%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 2.25rem;
}

.page-about .about-hero h1 {
  margin: 0.6rem 0 0;
  font-size: clamp(2rem, 6vw, 3.4rem);
  line-height: 1.1;
  letter-spacing: -0.01em;
}

.page-about .about-hero .eyebrow {
  color: var(--green);
}

.page-about .about-hero .lede {
  margin: 1rem 0 0;
  max-width: 62ch;
  color: rgba(255, 255, 255, 0.78);
  line-height: 1.85;
}

.page-about .about-hero .mono {
  color: var(--green);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.6rem;
}

.page-about .about-hero__vlabel {
  display: none;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  align-self: start;
  background: rgba(255, 255, 255, 0.16);
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.page-about .stat {
  background: var(--panel-2);
  padding: 1rem 1.05rem 1.1rem;
}

.page-about .stat__num {
  margin: 0;
  font-size: 1.7rem;
  line-height: 1;
  color: var(--green);
}

.page-about .stat__unit {
  font-size: 0.78rem;
  margin-left: 0.2rem;
}

.page-about .stat__label {
  margin: 0.55rem 0 0;
  font-size: 0.8rem;
  line-height: 1.5;
  color: rgba(255, 255, 255, 0.62);
}

/* ---------- 主体框架 ---------- */
.page-about .about-shell {
  display: grid;
  gap: 1.5rem;
  padding: 2.5rem 0 4rem;
}

.page-about .about-rail {
  border-left: var(--rail) solid var(--green);
  padding: 0.15rem 0 0.15rem 0.9rem;
}

.page-about .about-rail__label {
  margin: 0 0 0.5rem;
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  counter-reset: railc;
}

.page-about .about-rail__list li {
  counter-increment: railc;
}

.page-about .about-rail__list a {
  display: inline-block;
  font-size: 0.9rem;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.18s ease, color 0.18s ease;
}

.page-about .about-rail__list a::before {
  content: counter(railc, decimal-leading-zero) " ";
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--green-ink);
  margin-right: 0.25rem;
}

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

.page-about .about-rail__note {
  display: none;
  margin: 1rem 0 0;
  font-size: 0.75rem;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding: 2.25rem 0;
  border-top: 1px solid var(--line);
}

.page-about .about-flow > .about-sec:first-child {
  border-top: 0;
  padding-top: 0.5rem;
}

.page-about .sec-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.6rem 0.85rem;
  margin-bottom: 1rem;
}

.page-about .sec-head h2 {
  margin: 0;
  font-size: clamp(1.35rem, 3.4vw, 1.95rem);
  line-height: 1.25;
}

.page-about .sec-num {
  font-size: 0.75rem;
  padding: 0.2rem 0.5rem;
  background: var(--green-tint);
  color: var(--green-ink);
}

.page-about .sec-lede {
  margin: 0 0 1.5rem;
  max-width: 68ch;
  color: var(--muted);
  line-height: 1.85;
}

.page-about .about-sec h3 {
  font-size: 1.02rem;
  line-height: 1.45;
  margin: 0 0 0.4rem;
}

.page-about .about-sec p {
  line-height: 1.8;
}

/* ---------- 入口三卡 ---------- */
.page-about .entry-grid {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .entry-card {
  background: var(--paper);
  padding: 1.25rem 1.15rem 1.35rem;
  border-left: var(--rail) solid var(--green);
}

.page-about .entry-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.page-about .entry-card__link {
  margin-top: 0.85rem;
}

.page-about .entry-card__link a {
  font-size: 0.86rem;
  color: var(--green-ink);
  text-decoration: none;
  border-bottom: 1px solid var(--green);
  transition: color 0.18s ease, border-color 0.18s ease;
}

.page-about .entry-card__link a:hover,
.page-about .entry-card__link a:focus-visible {
  color: var(--orange);
  border-bottom-color: var(--orange);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0 0 1.5rem;
  border: 1px solid var(--line);
  box-shadow: 8px 8px 0 0 var(--green-tint);
}

.page-about .about-figure .media-frame__img {
  width: 100%;
  object-fit: cover;
}

/* ---------- 阶梯图 ---------- */
.page-about .stair-figure {
  margin: 0 0 1.75rem;
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 0.85rem;
}

.page-about .stair-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .stair-svg {
  display: block;
  width: 100%;
  min-width: 600px;
  height: auto;
}

.page-about .stair-axis {
  stroke: var(--line);
  stroke-width: 2;
}

.page-about .stair-rect--1 { fill: var(--about-t1); }
.page-about .stair-rect--2 { fill: var(--about-t2); }
.page-about .stair-rect--3 { fill: var(--about-t3); }
.page-about .stair-rect--4 { fill: var(--about-t4); }

.page-about .stair-years {
  font-family: var(--font-mono);
  font-size: 22px;
  fill: var(--ink);
  font-weight: 700;
}

.page-about .stair-cap {
  font-family: var(--font-sans);
  font-size: 17px;
  font-weight: 600;
}

.page-about .stair-cap--1 { fill: var(--green-ink); }
.page-about .stair-cap--2 { fill: var(--ink); }
.page-about .stair-cap--3 { fill: var(--paper); }
.page-about .stair-cap--4 { fill: var(--green); }

.page-about .stair-figure__cap {
  margin: 0.6rem 0 0;
  font-size: 0.78rem;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 档位卡 ---------- */
.page-about .tier-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.page-about .tier-card {
  --tc: var(--about-t1);
  background: var(--paper);
  border: 1px solid var(--line);
  border-top: 4px solid var(--tc);
  padding: 1rem 0.9rem 1.15rem;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.page-about .tier-card--1 { --tc: var(--about-t1); }
.page-about .tier-card--2 { --tc: var(--about-t2); }
.page-about .tier-card--3 { --tc: var(--about-t3); }
.page-about .tier-card--4 { --tc: var(--about-t4); }

.page-about .tier-card__badge {
  margin: 0 0 0.4rem;
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .tier-card h3 {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  margin: 0 0 0.35rem;
}

.page-about .tier-card__scope {
  margin: 0 0 0.7rem;
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--green-ink);
}

.page-about .tier-card__list {
  margin: 0;
  padding-left: 1.05rem;
  color: var(--muted);
  font-size: 0.85rem;
  line-height: 1.7;
}

.page-about .tier-card__list li + li {
  margin-top: 0.3rem;
}

@media (hover: hover) {
  .page-about .tier-card:hover {
    transform: translateY(-3px);
    border-color: var(--tc);
    box-shadow: 0 14px 26px -18px rgba(16, 20, 24, 0.55);
  }
}

/* ---------- 表格与提示 ---------- */
.page-about .rule-table {
  font-size: 0.9rem;
}

.page-about .rule-table td {
  vertical-align: top;
  line-height: 1.7;
}

.page-about .callout {
  margin-top: 1.25rem;
}

/* ---------- 工具与质检 ---------- */
.page-about .toolkit-grid {
  display: grid;
  gap: 1.25rem;
}

.page-about .tool-list {
  list-style: none;
  margin: 0 0 1.1rem;
  padding: 0;
  border: 1px solid var(--line);
  background: var(--paper);
}

.page-about .tool-list__item {
  display: grid;
  grid-template-columns: 3.1rem minmax(0, 1fr);
  gap: 0.85rem;
  align-items: start;
  padding: 1rem 0.95rem;
  border-bottom: 1px solid var(--line);
}

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

.page-about .tool-list__num {
  font-size: 1.9rem;
  line-height: 1;
  color: var(--green-ink);
  background: var(--green-tint);
  padding: 0.35rem 0.4rem;
  text-align: center;
}

.page-about .tool-list__item h3 {
  margin: 0 0 0.3rem;
}

.page-about .tool-list__item p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

.page-about .chip-row {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin: 0;
  padding: 0;
}

.page-about .toolkit-figure {
  margin: 0;
  border: 1px solid var(--line);
}

.page-about .toolkit-figure .media-frame__img {
  width: 100%;
  object-fit: cover;
}

.page-about .qa-strip {
  display: grid;
  gap: 1px;
  margin-top: 1.5rem;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .qa-item {
  background: var(--mist);
  padding: 1rem 0.95rem;
}

.page-about .qa-item__key {
  margin: 0 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .qa-item__val {
  margin: 0;
  font-size: 0.9rem;
  color: var(--ink);
  line-height: 1.75;
}

/* ---------- 服务网络 ---------- */
.page-about .city-grid {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 1.5rem;
  padding: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .city-tag {
  background: var(--paper);
  padding: 0.7rem 0.5rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  color: var(--ink);
  transition: background 0.18s ease, color 0.18s ease;
}

.page-about .city-tag:hover {
  background: var(--green);
  color: var(--ink);
}

.page-about .number-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--panel);
  border: 1px solid var(--panel);
}

.page-about .number-band__item {
  background: var(--panel-2);
  padding: 1.1rem 1rem 1.2rem;
}

.page-about .number-band__item--orange {
  background: var(--orange-tint);
}

.page-about .number-band__value {
  margin: 0;
  font-size: 1.6rem;
  line-height: 1;
  color: var(--green);
}

.page-about .number-band__item--orange .number-band__value {
  color: #8A3A00;
}

.page-about .number-band__label {
  margin: 0.5rem 0 0;
  font-size: 0.8rem;
  line-height: 1.5;
  color: rgba(255, 255, 255, 0.66);
}

.page-about .number-band__item--orange .number-band__label {
  color: var(--ink);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.5rem;
  border-left: 2px solid var(--line);
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 1.6rem;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -1.5rem;
  top: 0.4rem;
  width: 10px;
  height: 10px;
  margin-left: -6px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 3px var(--mist);
  transition: background 0.18s ease, box-shadow 0.18s ease;
}

.page-about .tl-item__stage {
  margin: 0 0 0.35rem;
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--muted);
  transition: color 0.18s ease;
}

.page-about .tl-item h3 {
  margin: 0 0 0.35rem;
  font-size: 1.05rem;
}

.page-about .tl-item p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--muted);
}

@media (hover: hover) {
  .page-about .tl-item:hover::before {
    background: var(--orange);
    box-shadow: 0 0 0 3px var(--orange-tint);
  }
  .page-about .tl-item:hover .tl-item__stage {
    color: var(--orange);
  }
}

/* ---------- 评优与边界 ---------- */
.page-about .badge-grid {
  display: grid;
  gap: 0.75rem;
}

.page-about .badge-card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-left: var(--rail) solid var(--green);
  padding: 1.1rem 1rem 1.2rem;
}

.page-about .badge-card--note {
  border-left-color: var(--orange);
  background: var(--orange-tint);
}

.page-about .badge-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--muted);
}

.page-about .badge-card--note p {
  color: var(--ink);
}

/* ---------- 结尾行动 ---------- */
.page-about .about-cta {
  display: grid;
  gap: 1.25rem;
  margin-top: 1.5rem;
  padding: 1.75rem 1.25rem;
  background: var(--panel);
  color: var(--paper);
  border-left: var(--rail) solid var(--green);
}

.page-about .about-cta h2 {
  margin: 0 0 0.6rem;
  font-size: clamp(1.2rem, 3vw, 1.6rem);
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-cta p {
  margin: 0;
  color: rgba(255, 255, 255, 0.74);
  line-height: 1.8;
  max-width: 62ch;
}

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

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .entry-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .city-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .number-band {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .qa-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .badge-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    align-items: center;
    padding: 2rem 1.75rem;
  }
  .page-about .about-cta__actions {
    justify-content: flex-end;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 3.5rem 0 5.5rem;
  }
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: start;
    gap: 3.5rem;
  }
  .page-about .about-hero__stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-shell {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 3rem;
    padding-top: 3rem;
  }
  .page-about .about-rail {
    position: sticky;
    top: 8rem;
    align-self: start;
    padding-left: 1.1rem;
  }
  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0.55rem;
  }
  .page-about .about-rail__note {
    display: block;
  }
  .page-about .tier-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .toolkit-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .city-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
  .page-about .number-band {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
  .page-about .badge-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-sec {
    padding: 3rem 0;
  }
}

@media (min-width: 1100px) {
  .page-about .about-hero__vlabel {
    display: block;
    position: absolute;
    right: 1.75rem;
    top: 5rem;
    z-index: 2;
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.34em;
    color: var(--green);
    opacity: 0.85;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tier-card,
  .page-about .tl-item::before,
  .page-about .tl-item__stage,
  .page-about .city-tag {
    transition: none;
  }
}