.section {
  width: var(--page);
  margin: 0 auto;
  padding: 118px 0;
  border-top: 1px solid var(--line);
}

.workflow {
  display: grid;
  grid-template-columns: minmax(280px, 0.82fr) minmax(420px, 1.18fr);
  gap: clamp(48px, 9vw, 130px);
}

.section-intro {
  align-self: start;
  position: sticky;
  top: 32px;
}

h2 {
  margin: 0;
  max-width: 13em;
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 700;
  letter-spacing: -0.05em;
  line-height: 1.08;
}

.section-intro > p:last-child {
  max-width: 34em;
  margin: 24px 0 0;
  color: var(--ink-soft);
  line-height: 1.75;
}

.workflow-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.workflow-list li {
  min-height: 150px;
  padding: 28px 0;
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 20px;
  border-top: 1px solid var(--line);
}

.workflow-list li:last-child {
  border-bottom: 1px solid var(--line);
}

.step-number {
  color: var(--brand);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  font-weight: 700;
}

.workflow-list h3,
.storage-columns h3 {
  margin: 0;
  font-size: 19px;
  font-weight: 680;
  letter-spacing: -0.025em;
}

.workflow-list p,
.storage-columns p {
  max-width: 42em;
  margin: 12px 0 0;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.78;
}

.storage-heading {
  display: grid;
  grid-template-columns: 0.7fr 1.3fr;
  gap: 32px;
  align-items: start;
}

.storage-columns {
  margin-top: 74px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--line);
}

.storage-columns article {
  min-width: 0;
  padding: 28px 42px 34px 0;
}

.storage-columns article + article {
  padding-left: 42px;
  border-left: 1px solid var(--line);
}

.surface-label {
  margin-bottom: 16px;
}

.capability-line {
  padding: 22px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  color: var(--ink-soft);
  font-size: 12px;
}

.closing {
  width: var(--page);
  margin: 0 auto;
  padding: 96px 0;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 40px;
  border-top: 1px solid var(--line);
}

footer {
  width: var(--page);
  min-height: 96px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 12px;
}

.footer-brand {
  color: var(--ink-soft);
  font-size: 14px;
}

@keyframes enter {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
}

@media (max-width: 980px) {
  :root {
    --page: min(100% - 40px, 820px);
  }

  .site-header {
    grid-template-columns: 1fr auto;
  }

  .site-nav {
    display: none;
  }

  .hero {
    min-height: auto;
    padding-top: 62px;
    grid-template-columns: 1fr;
  }

  .hero-copy {
    max-width: 680px;
  }

  h1 {
    max-width: 11em;
  }

  .map-window {
    width: min(100%, 760px);
  }

  .workflow {
    grid-template-columns: 1fr;
    gap: 60px;
  }

  .section-intro {
    position: static;
  }

  .workflow-list {
    max-width: 720px;
  }
}

@media (max-width: 620px) {
  :root {
    --page: calc(100% - 28px);
  }

  .site-header {
    min-height: 68px;
  }

  .brand-mark {
    width: 26px;
    height: 26px;
  }

  .header-cta {
    display: none;
  }

  .hero {
    padding: 48px 0 64px;
    gap: 46px;
  }

  h1 {
    font-size: clamp(39px, 13vw, 56px);
  }

  .hero-lead {
    font-size: 16px;
  }

  .primary-button {
    width: 100%;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .text-link {
    justify-content: center;
  }

  .map-stage {
    min-height: 420px;
  }

  .root-node {
    top: 46%;
    min-width: 100px;
  }

  .branch {
    max-width: 42%;
    padding-inline: 10px;
    font-size: 11px;
  }

  .branch-one {
    left: 5%;
  }

  .branch-two {
    right: 3%;
  }

  .branch-three {
    right: 3%;
    bottom: 22%;
  }

  .leaf {
    display: none;
  }

  .preview-detail {
    max-width: 76%;
  }

  .section {
    padding: 82px 0;
  }

  .workflow-list li {
    grid-template-columns: 42px 1fr;
    gap: 10px;
  }

  .storage-heading,
  .storage-columns {
    grid-template-columns: 1fr;
  }

  .storage-columns {
    margin-top: 48px;
  }

  .storage-columns article,
  .storage-columns article + article {
    padding: 26px 0 30px;
    border-left: 0;
  }

  .storage-columns article + article {
    border-top: 1px solid var(--line);
  }

  .closing {
    padding: 72px 0;
    align-items: stretch;
    flex-direction: column;
  }

  footer {
    padding: 28px 0;
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 1ms !important;
  }
}

@media (forced-colors: active) {
  .map-lines path {
    stroke: CanvasText;
  }

  .window-mark {
    border: 1px solid CanvasText;
  }
}

/* 下载区：沿用 storage-columns 的双卡栅格，按钮行与校验说明单独成行 */
.download-columns article {
  display: flex;
  flex-direction: column;
}

.download-columns article > p {
  flex: 1;
}

/* 两个下载选项是同一组件：几何尺寸相同，只用填充/描边区分推荐度 */
.download-actions {
  margin-top: 24px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  max-width: 380px;
}

.download-actions > a {
  flex: 1 1 140px;
}

.download-actions > a:only-child {
  flex: 0 1 auto;
  min-width: 152px;
}

/* 尺寸与 styles.css 中 .primary-button 的生效值对齐（52/22/15），仅配色区分主次 */
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  min-height: 52px;
  padding: 0 22px;
  border: 1px solid var(--ink);
  border-radius: 7px;
  color: var(--ink);
  background: transparent;
  font-size: 15px;
  font-weight: 650;
  text-decoration: none;
}

.secondary-button:hover {
  border-color: var(--brand);
  color: var(--brand);
  background: var(--brand-wash);
}

.secondary-button:active {
  transform: translateY(1px);
}

.download-sha .text-link {
  margin-left: 6px;
}

/* 校验值内联展示：文件名 + 哈希竖排，窄屏不横向溢出 */
.download-note {
  margin: 16px 0 0;
  color: var(--ink-soft);
  font-size: 12.5px;
  line-height: 1.7;
}

.download-note code {
  padding: 1px 6px;
  border: 1px solid var(--line);
  border-radius: 5px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px;
}

.download-sha {
  margin-top: 32px;
}