.page-about {
  --about-row: 12px;
  background: var(--navy);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

/* ===== 首屏封面 ===== */
.about-hero {
  position: relative;
  overflow: hidden;
  background: var(--navy);
  color: var(--paper);
  padding: 32px 20px 48px;
}

.about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 28px 28px;
  pointer-events: none;
}

.about-hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 100% 55%, 0 100%);
  pointer-events: none;
}

.about-hero__inner {
  position: relative;
  max-width: var(--shell);
  margin: 0 auto;
  display: grid;
  gap: 24px;
}

.about-hero__top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 16px;
  font-size: 0.85rem;
  color: rgba(244, 240, 230, 0.72);
}

.about-hero .breadcrumb {
  margin: 0;
  padding: 0;
  color: rgba(244, 240, 230, 0.7);
}

.about-hero .breadcrumb a {
  color: var(--white);
  text-decoration: none;
}

.about-hero .breadcrumb a:hover {
  color: var(--accent);
}

.about-hero__status {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
}

.about-hero__grid {
  display: grid;
  gap: 24px;
  align-items: center;
}

@media (min-width: 768px) {
  .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) 240px;
  }
}

.about-hero__kicker {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 10px;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: var(--fs-display);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--white);
  margin: 0 0 14px;
  max-width: 18em;
}

.about-hero__lede {
  font-size: 1rem;
  max-width: 34em;
  color: rgba(244, 240, 230, 0.86);
  margin: 0;
}

.about-hero__seal {
  width: 172px;
  height: 172px;
  margin: 0 auto;
  color: rgba(244, 240, 230, 0.6);
  border: 1px dashed rgba(255, 255, 255, 0.18);
  border-radius: 14px;
  padding: 8px;
}

@media (min-width: 768px) {
  .about-hero__seal {
    width: 214px;
    height: 214px;
    justify-self: end;
  }
}

.about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin: 8px 0 0;
}

@media (min-width: 640px) {
  .about-hero__stats {
    grid-template-columns: repeat(4, 1fr);
  }
}

.about-hero__stat {
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}

.about-hero__stat dt {
  font-size: 0.75rem;
  color: rgba(244, 240, 230, 0.64);
}

.about-hero__stat dd {
  font-family: var(--font-mono);
  font-size: 1.7rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--white);
  margin: 2px 0 0;
}

/* ===== 主体网格：索引 + 内容流 ===== */
.about-layout {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 32px 16px 72px;
  display: grid;
  gap: 28px;
}

@media (min-width: 980px) {
  .about-layout {
    grid-template-columns: 236px minmax(0, 1fr);
    align-items: start;
    gap: 44px;
    padding: 44px 24px 88px;
  }
}

.about-index {
  background: var(--navy-alt);
  color: var(--paper);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius);
  padding: 20px 16px;
}

@media (min-width: 980px) {
  .about-index {
    position: sticky;
    top: 24px;
    padding: 26px 22px;
  }
}

.about-index__kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  padding-bottom: 8px;
  margin: 0 0 12px;
}

.about-index__edition {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  opacity: 0.55;
  margin-bottom: 16px;
}

.about-index__list {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
  display: grid;
  gap: 4px;
}

@media (max-width: 979px) {
  .about-index__list {
    display: flex;
    overflow-x: auto;
    gap: 8px;
    padding-bottom: 4px;
  }
}

.about-index__list a {
  display: block;
  padding: 9px 12px;
  border-radius: 6px;
  color: rgba(244, 240, 230, 0.84);
  text-decoration: none;
  font-size: 0.9rem;
  white-space: nowrap;
  transition: background 0.2s ease, color 0.2s ease;
}

.about-index__list a:hover,
.about-index__list a.is-active {
  background: rgba(255, 106, 0, 0.22);
  color: var(--white);
}

.about-index__note {
  margin: 0 0 16px;
  font-size: 0.82rem;
  color: rgba(244, 240, 230, 0.7);
  border-left: 3px solid var(--accent);
  padding-left: 10px;
}

.about-index .btn--ghost {
  width: 100%;
}

/* ===== 内容流 ===== */
.about-content {
  display: grid;
  gap: 32px;
}

@media (min-width: 980px) {
  .about-content {
    gap: 42px;
  }
}

.about-section {
  position: relative;
  overflow: hidden;
  scroll-margin-top: 24px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 rgba(255, 255, 255, 0.04), 12px 12px 0 rgba(255, 255, 255, 0.02);
  padding: 26px 20px 30px;
}

.about-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 96px;
  height: 4px;
  background: var(--accent);
}

@media (min-width: 640px) {
  .about-section {
    padding: 34px 30px 40px;
  }
}

.about-section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  border-bottom: 2px solid var(--ink);
  box-shadow: 0 2px 0 0 rgba(12, 27, 58, 0.12);
  padding-bottom: 10px;
  margin-bottom: 24px;
}

.about-section__num {
  font-family: var(--font-mono);
  font-size: 3rem;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--accent);
}

@media (min-width: 640px) {
  .about-section__num {
    font-size: 3.6rem;
  }
}

.page-about .about-section h2 {
  font-family: var(--font-display);
  font-size: var(--fs-head);
  line-height: 1.22;
  letter-spacing: -0.01em;
  margin: 0;
}

.about-section__sub {
  flex: 1 1 100%;
  margin: 0;
  font-size: 0.83rem;
  color: var(--slate);
}

@media (min-width: 640px) {
  .about-section__sub {
    flex: 0 0 auto;
    margin-left: auto;
  }
}

/* ===== 章节 01：品牌定位 ===== */
.about-position-grid {
  display: grid;
  gap: 24px;
}

@media (min-width: 700px) {
  .about-position-grid {
    grid-template-columns: minmax(220px, 320px) minmax(0, 1fr);
    align-items: center;
    gap: 28px;
  }
}

.about-figure {
  margin: 0;
}

.about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 8px;
  object-fit: cover;
}

.about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--slate);
}

.about-prose p:first-of-type {
  margin-top: 0;
}

.about-directions {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.about-directions li {
  position: relative;
  padding: 10px 12px 10px 32px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  border-radius: 6px;
  font-size: 0.9rem;
}

.about-directions li::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 17px;
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 2px;
}

.about-notice {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 18px;
  padding: 12px 14px;
  background: var(--navy);
  color: var(--paper);
  border-radius: 6px;
  font-size: 0.88rem;
}

/* ===== 章节 02：发布机制 ===== */
.about-facts {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-bottom: 20px;
}

@media (min-width: 640px) {
  .about-facts {
    grid-template-columns: repeat(4, 1fr);
  }
}

.about-fact {
  background: var(--navy);
  color: var(--paper);
  border-radius: var(--radius-sm);
  padding: 16px 12px;
  text-align: center;
}

.about-fact__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.1;
  color: var(--accent);
}

.about-fact__label {
  display: block;
  margin-top: 4px;
  font-size: 0.78rem;
  color: rgba(244, 240, 230, 0.74);
}

.about-schedule {
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: 6px;
  padding: 18px 16px;
  margin-bottom: 14px;
}

.about-schedule__title {
  font-family: var(--font-display);
  font-weight: 700;
  margin: 0 0 10px;
}

.about-schedule__steps {
  margin: 0 0 12px;
  padding-left: 20px;
}

.about-schedule__steps li {
  margin-bottom: 6px;
  font-size: 0.9rem;
}

.about-schedule__note {
  margin: 0;
  border-top: 1px dashed var(--line);
  padding-top: 12px;
  font-size: 0.84rem;
  color: var(--slate);
}

.about-schedule__cta {
  margin-top: 8px;
}

/* ===== 章节 03：双版本架构 ===== */
.about-versions {
  display: grid;
  gap: 14px;
  margin-bottom: 20px;
}

@media (min-width: 640px) {
  .about-versions {
    grid-template-columns: repeat(2, 1fr);
  }
}

.version-card {
  position: relative;
  background: var(--white);
  border: 1px solid var(--line);
  border-top: 4px solid var(--moss);
  border-radius: 8px;
  padding: 18px 16px 16px;
  box-shadow: 0 2px 0 rgba(12, 27, 58, 0.06);
}

.version-card--lite {
  border-top-color: var(--clay);
}

.version-card__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 8px;
}

.version-card h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.05rem;
}

.version-card p {
  margin: 0 0 12px;
  font-size: 0.88rem;
}

.about-compare {
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px;
  margin-bottom: 20px;
}

.about-compare h3 {
  margin: 0 0 6px;
}

.about-compare p {
  margin: 0 0 12px;
  font-size: 0.9rem;
}

.about-compare__table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin-bottom: 14px;
  background: var(--white);
}

.about-compare__table th,
.about-compare__table td {
  border: 1px solid var(--line);
  padding: 8px 10px;
  text-align: left;
}

.about-compare__table th {
  background: var(--navy);
  color: var(--paper);
  font-weight: 600;
  white-space: nowrap;
}

/* ===== 章节 04：国内面板 ===== */
.about-panel__lead {
  margin: 0 0 18px;
  font-size: 0.95rem;
}

.about-steps {
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  display: grid;
  gap: 8px;
  counter-reset: about-step;
}

.about-steps li {
  counter-increment: about-step;
  display: grid;
  grid-template-columns: 34px 80px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 12px;
}

.about-steps li::before {
  content: "0" counter(about-step);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent);
  border: 1px solid var(--accent);
  border-radius: 4px;
  padding: 2px 6px;
  text-align: center;
  width: 28px;
  box-sizing: border-box;
}

.about-steps__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.92rem;
}

.about-steps li p {
  margin: 0;
  font-size: 0.88rem;
}

.about-panel-tip {
  background: var(--moss);
  color: var(--white);
  border-radius: 6px;
  padding: 12px 14px;
  font-size: 0.88rem;
}

/* ===== 章节 05：服务边界与备案 ===== */
.about-license {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  background: var(--white);
  border: 2px solid var(--ink);
  outline: 3px solid rgba(255, 106, 0, 0.25);
  outline-offset: 3px;
  border-radius: 6px;
  padding: 14px 16px;
  margin-bottom: 18px;
}

.about-license__tip {
  flex-basis: 100%;
  font-size: 0.84rem;
  color: var(--slate);
}

.about-contact-grid {
  display: grid;
  gap: 10px;
  margin-bottom: 18px;
}

@media (min-width: 640px) {
  .about-contact-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.about-contact-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 12px 14px;
}

.about-contact-card h3 {
  margin: 0 0 4px;
  font-size: 0.92rem;
}

.about-contact-card p {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.84rem;
  word-break: break-all;
}

.about-boundary-note {
  margin: 0 0 18px;
  padding-left: 12px;
  border-left: 3px solid var(--silver);
  font-size: 0.85rem;
  color: var(--slate);
}

.about-snapshot {
  background: var(--navy);
  color: var(--paper);
  border-radius: 6px;
  padding: 14px 16px;
  margin-bottom: 18px;
}

.about-snapshot summary {
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fs-head);
  padding: 4px 0;
}

.about-snapshot summary::before {
  content: "";
  display: inline-flex;
  width: 12px;
  height: 12px;
  border: 2px solid var(--accent);
  border-radius: 3px;
  transform: rotate(45deg);
  transition: transform 0.2s ease;
}

.about-snapshot details[open] summary::before {
  transform: rotate(0deg);
}

.about-snapshot dl {
  margin: 14px 0 0;
  display: grid;
  gap: 6px;
}

.about-snapshot div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 10px;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.18);
  padding-bottom: 6px;
}

.about-snapshot dt {
  font-size: 0.86rem;
  color: rgba(244, 240, 230, 0.72);
}

.about-snapshot dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--accent);
  text-align: right;
}

.about-snapshot a {
  color: var(--accent-soft);
  text-decoration: none;
}

.about-snapshot a:hover {
  color: var(--accent);
}