.page-platform {
  --p-hair: color-mix(in srgb, var(--color-primary) 45%, transparent);
  --p-glass: color-mix(in srgb, var(--color-surface-alt) 76%, transparent);
  --p-rule-strong: color-mix(in srgb, var(--color-primary) 60%, transparent);
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  overflow-x: hidden;
}

.page-platform .num {
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
  font-variant-numeric: tabular-nums;
}

/* ================= 首屏 ================= */
.page-platform .sys-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: var(--space-6) 0 var(--space-8);
  border-bottom: 1px solid var(--color-line);
  background-color: var(--color-surface);
}

.page-platform .sys-hero__media {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.page-platform .sys-hero__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 62% 50%;
}

.page-platform .sys-hero__scrim {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--color-surface) 52%, transparent) 0%,
    color-mix(in srgb, var(--color-surface) 86%, transparent) 62%,
    var(--color-surface) 100%
  );
}

.page-platform .sys-hero__inner {
  display: grid;
  gap: var(--space-3);
}

.page-platform .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
}

.page-platform .breadcrumb a {
  color: var(--color-ink-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.25s ease, border-color 0.25s ease;
}

.page-platform .breadcrumb a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.page-platform .breadcrumb__item[aria-current="page"] {
  color: var(--color-ink-soft);
}

.page-platform .eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-ink-soft);
}

.page-platform .sys-hero__title {
  margin: var(--space-2) 0 0;
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: 1.02;
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  overflow-wrap: anywhere;
}

.page-platform .sys-hero__desc {
  max-width: var(--measure);
  margin: var(--space-3) 0 0;
  font-size: var(--text-lg);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-platform .sys-hero__figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.page-platform .fig {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  background: var(--p-glass);
  box-shadow: var(--shadow-1);
}

.page-platform .fig__val {
  font-family: var(--font-mono);
  font-size: var(--text-2xl);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--color-accent);
}

.page-platform .fig__key {
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-soft);
}

/* ================= 通用区块头 ================= */
.page-platform .sec-head {
  display: grid;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
}

.page-platform .section-number {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  line-height: 1;
  letter-spacing: 0.32em;
  color: var(--color-primary);
}

.page-platform .sec-head__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-3xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .sec-head__lead {
  margin: 0;
  max-width: var(--measure);
  color: var(--color-ink-soft);
}

/* ================= 分类骨架 ================= */
.page-platform .sys-band {
  margin: 0 0 var(--space-6);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-platform .sys-band img {
  display: block;
  width: 100%;
  height: 150px;
  object-fit: cover;
}

.page-platform .cat-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-3);
}

.page-platform .cat {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    "no body"
    "meta meta";
  gap: var(--space-2) var(--space-3);
  align-items: start;
  padding: var(--space-3);
  border: 1px solid var(--color-line);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-md);
}

.page-platform .cat--a {
  background: var(--color-primary-soft);
}

.page-platform .cat--b {
  background: var(--color-surface-alt);
  border-left-color: var(--color-accent);
}

.page-platform .cat--c {
  background: var(--color-surface-deep);
}

.page-platform .cat--d {
  background: var(--color-highlight);
  border-left-color: var(--color-accent);
}

.page-platform .cat__no {
  grid-area: no;
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  line-height: 1.1;
  letter-spacing: 0.08em;
  color: var(--color-accent);
}

.page-platform .cat__body {
  grid-area: body;
}

.page-platform .cat__name {
  margin: 0 0 var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .cat__desc {
  margin: 0;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

.page-platform .cat__meta {
  grid-area: meta;
  align-self: end;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
  white-space: nowrap;
}

.page-platform .cat__meta .num {
  color: var(--color-accent);
}

/* ================= 目录区 ================= */
.page-platform .dir-jump {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-bottom: var(--space-6);
}

.page-platform .dir-jump__link {
  padding: var(--space-1) var(--space-2);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-pill);
  background: var(--color-primary-soft);
  color: var(--color-ink);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: box-shadow 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.page-platform .dir-jump__link:hover,
.page-platform .dir-jump__link:focus-visible {
  box-shadow: var(--shadow-1);
  border-color: var(--p-rule-strong);
  color: var(--color-accent);
}

.page-platform .dir {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-platform .dir__item {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  grid-template-areas:
    "no body"
    ". meta";
  gap: var(--space-1) var(--space-3);
  align-items: baseline;
  padding: var(--space-3) 0;
  border-top: 1px solid var(--color-line);
  transition: box-shadow 0.35s ease, background-color 0.35s ease;
}

.page-platform .dir__item:nth-child(4n) {
  padding-bottom: calc(var(--space-3) + var(--space-3));
  border-bottom: 1px solid var(--p-rule-strong);
}

.page-platform .dir__no {
  grid-area: no;
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  line-height: 1.2;
  letter-spacing: 0.04em;
  color: var(--color-primary);
}

.page-platform .dir__body {
  grid-area: body;
}

.page-platform .dir__title {
  margin: 0 0 var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .dir__desc {
  margin: 0;
  max-width: 58ch;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-ink-soft);
}

.page-platform .dir__tag {
  grid-area: meta;
  justify-self: start;
  padding: calc(var(--space-1) * 0.5) var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--color-primary-soft);
  color: var(--color-ink);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  white-space: nowrap;
}

.page-platform .dir__count {
  grid-area: meta;
  justify-self: end;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  white-space: nowrap;
  transition: color 0.3s ease;
}

.page-platform .dir__count .num {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

/* ================= 字段字典（浅色强对比带） ================= */
.page-platform .dict-band {
  padding-block: var(--space-8);
}

.page-platform .dict-band .section-number {
  color: var(--color-contrast-accent);
}

.page-platform .dict-band .sec-head__title {
  color: var(--color-contrast-ink);
}

.page-platform .dict-band .sec-head__lead {
  color: var(--color-contrast-ink);
}

.page-platform .dict-band__grid {
  display: grid;
  gap: var(--space-6);
}

.page-platform .dict-band__side {
  display: grid;
  gap: var(--space-2);
}

.page-platform .dict-band__figure {
  margin: 0;
  border: 1px solid var(--color-contrast-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-platform .dict-band__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-platform .dict-band__caption {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  line-height: 1.7;
  color: var(--color-contrast-ink);
  opacity: 0.78;
}

.page-platform .dict-accordion {
  display: grid;
  gap: var(--space-2);
}

.page-platform .dict-band .accordion__item {
  border: 1px solid var(--color-contrast-line);
  border-radius: var(--radius-md);
  background: var(--color-contrast-surface);
  overflow: hidden;
}

.page-platform .dict-band .accordion__head {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border: 0;
  background: transparent;
  color: var(--color-contrast-ink);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  text-align: left;
  cursor: pointer;
}

.page-platform .dict-band .accordion__head:focus-visible {
  outline: 2px solid var(--color-contrast-accent);
  outline-offset: -2px;
}

.page-platform .dict-band .accordion__icon {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  line-height: 1;
  color: var(--color-contrast-accent);
}

.page-platform .dict-band .accordion__panel {
  padding: 0 var(--space-3) var(--space-3);
}

.page-platform .dict-band .accordion__panel p {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-contrast-ink);
}

/* ================= 更新与校验节奏 ================= */
.page-platform .cadence__grid {
  display: grid;
  gap: var(--space-3);
}

.page-platform .cadence__item {
  padding: var(--space-3);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
}

.page-platform .cadence__item:nth-child(1) {
  box-shadow: var(--shadow-1);
  border-color: var(--p-rule-strong);
}

.page-platform .cadence__item:nth-child(3) {
  background: var(--color-surface-deep);
}

.page-platform .cadence__no {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.22em;
  color: var(--color-accent);
}

.page-platform .cadence__title {
  margin: var(--space-2) 0 var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .cadence__desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-ink-soft);
}

.page-platform .cadence__note {
  margin: var(--space-6) 0 0;
  max-width: var(--measure);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

.page-platform .cadence__note a {
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid var(--p-hair);
  transition: border-color 0.25s ease;
}

.page-platform .cadence__note a:hover {
  border-bottom-color: var(--color-accent);
}

/* ================= 过渡横带 ================= */
.page-platform .sys-transition {
  margin: 0;
  border-top: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
  overflow: hidden;
}

.page-platform .sys-transition img {
  display: block;
  width: 100%;
  height: 180px;
  object-fit: cover;
}

/* ================= 下钻入口 ================= */
.page-platform .drill__panel {
  display: grid;
  gap: var(--space-4);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
}

.page-platform .drill__title {
  margin: var(--space-2) 0 var(--space-2);
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-platform .drill__desc {
  margin: 0;
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-ink-soft);
}

.page-platform .drill .btn {
  justify-self: start;
  text-decoration: none;
}

/* ================= 平板与桌面 ================= */
@media (min-width: 760px) {
  .page-platform .sys-band img {
    height: 190px;
  }

  .page-platform .sys-hero__figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: var(--space-3);
  }

  .page-platform .cadence__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--space-4);
  }

  .page-platform .cadence__item:nth-child(2) {
    margin-top: var(--space-4);
  }

  .page-platform .cadence__item:nth-child(3) {
    margin-top: var(--space-2);
  }

  .page-platform .cat {
    grid-template-columns: auto minmax(0, 1fr) auto;
    grid-template-areas: "no .page-platform meta";
    align-items: center;
  }

  .page-platform .cat__meta {
    align-self: center;
  }

  .page-platform .sys-transition img {
    height: 240px;
  }
}

@media (min-width: 880px) {
  .page-platform .sys-hero {
    padding: var(--space-8) 0 var(--section-y);
  }

  .page-platform .sys-hero__scrim {
    background: linear-gradient(
      102deg,
      var(--color-surface) 0%,
      color-mix(in srgb, var(--color-surface) 88%, transparent) 44%,
      color-mix(in srgb, var(--color-surface) 28%, transparent) 100%
    );
  }

  .page-platform .cat:nth-child(1) {
    margin-right: 9%;
  }

  .page-platform .cat:nth-child(2) {
    margin-left: 9%;
  }

  .page-platform .cat:nth-child(3) {
    margin-right: 4%;
  }

  .page-platform .cat:nth-child(4) {
    margin-left: 4%;
  }

  .page-platform .drill__panel {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: var(--space-6);
    padding: var(--space-6);
  }

  .page-platform .drill .btn {
    justify-self: end;
  }
}

@media (min-width: 900px) {
  .page-platform .dir__item {
    grid-template-columns: 78px minmax(0, 1fr) 130px 120px;
    grid-template-areas: "no .page-platform tag count";
    gap: var(--space-3);
    padding: var(--space-3) var(--space-2);
    border-radius: var(--radius-sm);
    border-top-color: var(--color-line);
  }

  .page-platform .dir__item:nth-child(4n) {
    padding-bottom: calc(var(--space-3) + var(--space-2));
  }

  .page-platform .dir__item:hover,
  .page-platform .dir__item:focus-within {
    background: color-mix(in srgb, var(--color-surface-alt) 62%, transparent);
    box-shadow: var(--shadow-1);
  }

  .page-platform .dir__item:hover .dir__count .num,
  .page-platform .dir__item:focus-within .dir__count .num {
    color: var(--color-accent);
  }

  .page-platform .dir__item .dir__tag {
    grid-area: tag;
    justify-self: start;
    align-self: start;
  }

  .page-platform .dir__item .dir__count {
    grid-area: count;
    justify-self: end;
    align-self: start;
  }
}

@media (min-width: 960px) {
  .page-platform .dict-band__grid {
    grid-template-columns: minmax(0, 300px) minmax(0, 1fr);
    gap: var(--space-8);
    align-items: start;
  }
}