:root {
  color-scheme: light;
  --page: #f4f6f8;
  --surface: #ffffff;
  --ink: #17202a;
  --muted: #66717f;
  --faint: #8d97a3;
  --line: #e2e6ea;
  --line-strong: #cfd5db;
  --accent: #8055e6;
  --accent-dark: #6338c7;
  --accent-soft: #f2edff;
  --link: #1768c4;
  --green: #147d65;
  --green-soft: #eaf7f3;
  --yellow-soft: #fff7e8;
  --navy: #12233f;
  --shadow: 0 12px 34px rgba(21, 31, 43, 0.06);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  font-synthesis: none;
  letter-spacing: 0;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 92px;
}

body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  background: var(--page);
  color: var(--ink);
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 12px;
  z-index: 100;
  padding: 8px 12px;
  border-radius: 4px;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.reading-progress {
  position: fixed;
  inset: 0 0 auto;
  z-index: 80;
  height: 2px;
  pointer-events: none;
}

.reading-progress span {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left center;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  border-bottom: 1px solid rgba(207, 213, 219, 0.9);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1180px, calc(100% - 40px));
  height: 64px;
  margin: 0 auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  color: var(--ink);
  text-decoration: none;
}

.brand img {
  flex: 0 0 auto;
  border-radius: 7px;
}

.brand-copy {
  display: flex;
  align-items: baseline;
  gap: 9px;
  white-space: nowrap;
}

.brand-copy strong {
  font-size: 16px;
  line-height: 1;
}

.brand-copy small {
  color: var(--muted);
  font-size: 13px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 20px;
}

.guide-label {
  color: var(--muted);
  font-size: 13px;
}

.console-button,
.section-action a,
.finish-band > a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-height: 38px;
  border: 1px solid var(--accent);
  border-radius: 6px;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  font-weight: 650;
  line-height: 1;
  text-decoration: none;
  transition: background-color 160ms ease, border-color 160ms ease, transform 160ms ease;
}

.console-button {
  padding: 0 15px;
}

.console-button:hover,
.section-action a:hover,
.finish-band > a:hover {
  border-color: var(--accent-dark);
  background: var(--accent-dark);
  transform: translateY(-1px);
}

.button-label-short,
.mobile-nav {
  display: none;
}

.page-shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 32px 0 56px;
}

.content-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 210px;
  gap: 32px;
  align-items: start;
}

.doc-surface {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.doc-hero,
.doc-section {
  padding: 48px 54px;
}

.doc-hero {
  padding-bottom: 44px;
  border-bottom: 1px solid var(--line);
}

.eyebrow-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 17px;
}

.eyebrow {
  color: var(--accent-dark);
  font-size: 13px;
  font-weight: 750;
}

.reading-time {
  color: var(--faint);
  font-size: 12px;
}

.doc-hero h1 {
  margin: 0;
  color: var(--ink);
  font-size: 36px;
  line-height: 1.22;
  letter-spacing: 0;
}

.hero-summary {
  max-width: 650px;
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.journey {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 34px 0;
  border-block: 1px solid var(--line-strong);
}

.journey a {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 14px 10px;
  color: var(--ink);
  text-decoration: none;
}

.journey a + a {
  border-left: 1px solid var(--line);
}

.journey span {
  color: var(--accent);
  font-size: 11px;
  font-weight: 750;
}

.journey strong {
  overflow: hidden;
  font-size: 13px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.notice {
  display: flex;
  gap: 13px;
  padding: 15px 17px;
  border-left: 3px solid var(--line-strong);
  border-radius: 0 6px 6px 0;
}

.notice-mark {
  display: grid;
  flex: 0 0 22px;
  width: 22px;
  height: 22px;
  place-items: center;
  border-radius: 50%;
  font-size: 12px;
  font-style: normal;
  font-weight: 800;
  line-height: 1;
}

.notice strong {
  display: block;
  margin: -2px 0 2px;
  color: var(--ink);
  font-size: 13px;
}

.notice p {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.65;
}

.notice-neutral {
  border-color: #95a2b0;
  background: #f5f7f9;
}

.notice-neutral .notice-mark {
  background: #dfe5eb;
  color: #4a5b6c;
}

.notice-warning {
  margin-top: 24px;
  border-color: #d78a22;
  background: var(--yellow-soft);
}

.notice-warning .notice-mark {
  background: #f8dca8;
  color: #7a4304;
}

.notice-success {
  margin-top: 24px;
  border-color: var(--green);
  background: var(--green-soft);
}

.notice-success .notice-mark {
  background: #c8ebdf;
  color: var(--green);
}

.doc-section {
  scroll-margin-top: 88px;
}

.doc-section + .doc-section {
  border-top: 1px solid var(--line);
}

.section-heading {
  display: flex;
  align-items: center;
  gap: 15px;
  margin-bottom: 13px;
}

.section-number {
  display: grid;
  flex: 0 0 42px;
  width: 42px;
  height: 42px;
  place-items: center;
  border: 1px solid #f1c1ad;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 12px;
  font-weight: 800;
}

.section-kicker {
  margin: 0 0 1px;
  color: var(--accent-dark);
  font-size: 11px;
  font-weight: 750;
}

.section-heading h2 {
  margin: 0;
  font-size: 25px;
  line-height: 1.3;
}

.section-intro {
  max-width: 680px;
  margin: 0 0 28px;
  color: var(--muted);
}

.instructions {
  display: grid;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.instructions li {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 13px;
}

.instruction-number {
  display: grid;
  width: 28px;
  height: 28px;
  margin-top: 1px;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
}

.instructions strong {
  display: block;
  margin-bottom: 2px;
  color: var(--ink);
  font-size: 14px;
}

.instructions p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.instructions a {
  color: var(--link);
  font-weight: 600;
  text-underline-offset: 3px;
}

code {
  padding: 2px 5px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: #f5f7f9;
  color: #324050;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px;
  overflow-wrap: anywhere;
}

.ui-preview {
  margin: 32px 0 0;
}

.ui-preview figcaption {
  margin-bottom: 9px;
  color: var(--faint);
  font-size: 11px;
}

.browser-frame {
  overflow: hidden;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 8px 24px rgba(22, 34, 48, 0.08);
}

.shot-link {
  display: block;
  background: #eeebfa;
  cursor: zoom-in;
}

.page-shot {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
}

.browser-bar {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr) 62px;
  align-items: center;
  min-height: 36px;
  padding: 0 12px;
  border-bottom: 1px solid #dce1e6;
  background: #eef1f4;
}

.browser-dots {
  display: flex;
  gap: 5px;
}

.browser-dots i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #b9c0c8;
}

.browser-dots i:first-child {
  background: #e98569;
}

.browser-dots i:nth-child(2) {
  background: #e1b859;
}

.browser-dots i:nth-child(3) {
  background: #73bb8f;
}

.browser-address {
  min-width: 0;
  overflow: hidden;
  padding: 3px 12px;
  border: 1px solid #dde2e7;
  border-radius: 4px;
  background: #fff;
  color: #74808c;
  font-size: 9px;
  line-height: 1.4;
  text-align: center;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.auth-scene {
  display: grid;
  grid-template-columns: minmax(130px, 0.65fr) minmax(240px, 1fr);
  min-height: 318px;
  background: #f6f8fa;
}

.auth-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: var(--navy);
  color: #fff;
}

.auth-brand img {
  border-radius: 8px;
}

.auth-brand strong {
  font-size: 13px;
}

.mock-form {
  align-self: center;
  width: min(260px, calc(100% - 44px));
  margin: 28px auto;
  padding: 22px;
  border: 1px solid #e0e5ea;
  border-radius: 7px;
  background: #fff;
  box-shadow: 0 8px 24px rgba(22, 34, 48, 0.05);
}

.mock-form-heading {
  display: flex;
  flex-direction: column;
  margin-bottom: 14px;
}

.mock-form-heading strong {
  color: #1c2733;
  font-size: 14px;
}

.mock-form-heading span {
  color: #8c96a1;
  font-size: 8px;
}

.mock-form label,
.redeem-panel label {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  margin: 9px 0;
  color: #4d5966;
  font-size: 8px;
  font-weight: 650;
}

.mock-form label small {
  margin-left: 3px;
  color: #9ca5ae;
  font-size: 7px;
  font-weight: 500;
}

.mock-form label span,
.redeem-panel label span {
  flex: 0 0 100%;
  height: 26px;
  margin-top: 3px;
  padding: 6px 8px;
  border: 1px solid #dfe4e9;
  border-radius: 4px;
  color: #a0a8b0;
  font-size: 8px;
  font-weight: 400;
}

.mock-primary {
  display: grid;
  width: 100%;
  min-height: 27px;
  margin-top: 12px;
  place-items: center;
  border-radius: 4px;
  background: var(--accent);
  color: #fff;
  font-size: 8px;
  font-weight: 750;
}

.mock-form p {
  margin: 10px 0 0;
  color: #9ba4ad;
  font-size: 7px;
  text-align: center;
}

.mock-form em {
  color: var(--link);
  font-style: normal;
}

.dashboard-scene,
.account-scene {
  display: grid;
  grid-template-columns: 128px minmax(0, 1fr);
  min-height: 330px;
  background: #f5f7f9;
}

.mock-sidebar {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 10px;
  border-right: 1px solid #e2e6ea;
  background: #fff;
}

.mock-sidebar > span {
  padding: 7px 9px;
  border-radius: 4px;
  color: #687481;
  font-size: 8px;
}

.mock-sidebar .sidebar-brand {
  display: flex;
  align-items: center;
  gap: 7px;
  margin-bottom: 10px;
  padding: 0 5px 10px;
  border-bottom: 1px solid #edf0f2;
  color: var(--ink);
  font-size: 9px;
}

.sidebar-brand img {
  border-radius: 5px;
}

.mock-sidebar .is-selected {
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-weight: 700;
}

.mock-workspace {
  min-width: 0;
  padding: 25px 28px;
}

.mock-page-title {
  display: flex;
  flex-direction: column;
  margin-bottom: 18px;
}

.mock-page-title strong {
  color: #1c2733;
  font-size: 14px;
}

.mock-page-title span {
  color: #8b96a1;
  font-size: 8px;
}

.redeem-panel,
.subscription-panel {
  max-width: 390px;
  padding: 24px;
  border: 1px solid #e0e5e9;
  border-radius: 7px;
  background: #fff;
  box-shadow: 0 7px 20px rgba(22, 34, 48, 0.04);
}

.redeem-panel {
  display: grid;
  justify-items: start;
}

.redeem-icon {
  display: grid;
  width: 28px;
  height: 28px;
  margin-bottom: 10px;
  place-items: center;
  border-radius: 6px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 11px;
  font-weight: 800;
}

.redeem-panel > strong {
  font-size: 11px;
}

.redeem-panel > p {
  margin: 2px 0 9px;
  color: #8b96a1;
  font-size: 8px;
}

.redeem-panel label {
  width: 100%;
}

.subscription-topline,
.quota-row,
.subscription-meta {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
}

.subscription-topline > div {
  display: flex;
  flex-direction: column;
}

.subscription-topline span,
.quota-row span,
.subscription-meta small {
  color: #8b96a1;
  font-size: 8px;
}

.subscription-topline > div strong {
  font-size: 13px;
}

.subscription-topline > b {
  padding: 3px 7px;
  border-radius: 4px;
  background: var(--green-soft);
  color: var(--green);
  font-size: 8px;
}

.quota-row {
  margin-top: 23px;
}

.quota-row strong {
  color: #526170;
  font-size: 8px;
}

.quota-track {
  height: 6px;
  margin-top: 7px;
  overflow: hidden;
  border-radius: 3px;
  background: #edf0f2;
}

.quota-track i {
  display: block;
  width: 38%;
  height: 100%;
  border-radius: inherit;
  background: var(--green);
}

.subscription-meta {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid #edf0f2;
}

.subscription-meta span {
  display: flex;
  flex-direction: column;
}

.subscription-meta b {
  color: #53606d;
  font-size: 8px;
}

.section-action {
  display: flex;
  justify-content: flex-end;
  margin-top: 24px;
}

.section-action a {
  min-width: 132px;
  padding: 0 15px;
}

.confirmation-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin-top: 24px;
  padding: 17px 19px;
  border-block: 1px solid var(--line);
}

.confirmation-list > strong {
  margin-bottom: 2px;
  font-size: 13px;
}

.confirmation-list span {
  display: flex;
  align-items: center;
  gap: 9px;
  color: var(--muted);
  font-size: 13px;
}

.confirmation-list i {
  display: grid;
  width: 18px;
  height: 18px;
  place-items: center;
  border-radius: 50%;
  background: var(--green-soft);
  color: var(--green);
  font-size: 10px;
  font-style: normal;
  font-weight: 800;
}

.finish-band {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) auto;
  align-items: center;
  gap: 17px;
  padding: 32px 54px;
  border-top: 1px solid #cfe6de;
  background: #f2faf7;
}

.finish-check {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border-radius: 50%;
  background: var(--green);
  color: #fff;
  font-size: 18px;
  font-weight: 800;
}

.finish-band h2 {
  margin: 0 0 2px;
  font-size: 18px;
}

.finish-band p {
  margin: 0;
  color: #60746f;
  font-size: 13px;
}

.finish-band > a {
  min-width: 124px;
  padding: 0 14px;
  border-color: var(--green);
  background: var(--green);
}

.finish-band > a:hover {
  border-color: #0d6350;
  background: #0d6350;
}

.toc {
  position: sticky;
  top: 88px;
  padding-top: 8px;
}

.toc > p {
  margin: 0 0 12px;
  color: var(--ink);
  font-size: 12px;
  font-weight: 750;
}

.toc nav {
  display: grid;
  border-left: 1px solid var(--line-strong);
}

.toc nav a {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-left: -1px;
  padding: 8px 0 8px 14px;
  border-left: 2px solid transparent;
  color: var(--muted);
  font-size: 13px;
  text-decoration: none;
  transition: border-color 150ms ease, color 150ms ease;
}

.toc nav a span {
  color: var(--faint);
  font-size: 10px;
}

.toc nav a:hover,
.toc nav a.is-active {
  border-left-color: var(--accent);
  color: var(--ink);
}

.toc nav a.is-active span {
  color: var(--accent);
}

.toc-help {
  display: grid;
  gap: 2px;
  margin-top: 25px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: 12px;
}

.toc-help span {
  color: var(--faint);
}

.toc-help a {
  color: var(--link);
  font-weight: 650;
  text-decoration: none;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: #fff;
}

.site-footer > div {
  display: flex;
  justify-content: space-between;
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 23px 0;
  color: var(--faint);
  font-size: 12px;
}

.back-to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 40;
  display: grid;
  width: 40px;
  height: 40px;
  padding: 0;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 7px 20px rgba(22, 34, 48, 0.1);
  color: var(--ink);
  cursor: pointer;
  font-size: 18px;
  opacity: 0;
  pointer-events: none;
  transform: translateY(8px);
  transition: opacity 160ms ease, transform 160ms ease, border-color 160ms ease;
}

.back-to-top:hover {
  border-color: var(--accent);
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

:focus-visible {
  outline: 3px solid rgba(23, 104, 196, 0.34);
  outline-offset: 3px;
}

@media (max-width: 960px) {
  html {
    scroll-padding-top: 116px;
  }

  .site-header {
    box-shadow: 0 3px 14px rgba(22, 34, 48, 0.04);
  }

  .mobile-nav {
    display: flex;
    gap: 22px;
    overflow-x: auto;
    width: min(100%, 760px);
    margin: 0 auto;
    padding: 0 20px;
    scrollbar-width: none;
  }

  .mobile-nav::-webkit-scrollbar {
    display: none;
  }

  .mobile-nav a {
    flex: 0 0 auto;
    padding: 0 0 10px;
    border-bottom: 2px solid transparent;
    color: var(--muted);
    font-size: 12px;
    text-decoration: none;
  }

  .mobile-nav a.is-active {
    border-bottom-color: var(--accent);
    color: var(--ink);
  }

  .page-shell {
    padding-top: 24px;
  }

  .content-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .toc {
    display: none;
  }

  .doc-section {
    scroll-margin-top: 116px;
  }
}

@media (max-width: 680px) {
  .header-inner,
  .page-shell,
  .site-footer > div {
    width: min(100% - 24px, 1180px);
  }

  .header-inner {
    height: 58px;
  }

  .brand img {
    width: 30px;
    height: 30px;
  }

  .brand-copy {
    display: grid;
    gap: 1px;
  }

  .brand-copy strong {
    font-size: 14px;
  }

  .brand-copy small {
    font-size: 10px;
  }

  .guide-label,
  .button-label-full {
    display: none;
  }

  .button-label-short {
    display: inline;
  }

  .console-button {
    min-height: 34px;
    padding: 0 11px;
    font-size: 12px;
  }

  .mobile-nav {
    gap: 20px;
    padding: 0 12px;
  }

  .page-shell {
    padding: 12px 0 36px;
  }

  .doc-hero,
  .doc-section {
    padding: 30px 22px;
  }

  .doc-hero h1 {
    font-size: 29px;
  }

  .hero-summary {
    font-size: 15px;
  }

  .reading-time {
    font-size: 10px;
  }

  .journey {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .journey a:nth-child(3) {
    border-top: 1px solid var(--line);
    border-left: 0;
  }

  .journey a:nth-child(4) {
    border-top: 1px solid var(--line);
  }

  .section-heading {
    align-items: flex-start;
  }

  .section-number {
    flex-basis: 38px;
    width: 38px;
    height: 38px;
  }

  .section-heading h2 {
    font-size: 21px;
  }

  .auth-scene {
    grid-template-columns: 78px minmax(0, 1fr);
    min-height: 288px;
  }

  .auth-brand strong {
    display: none;
  }

  .auth-brand img {
    width: 31px;
    height: 31px;
  }

  .mock-form {
    width: min(230px, calc(100% - 24px));
    margin: 18px auto;
    padding: 15px;
  }

  .browser-bar {
    grid-template-columns: 42px minmax(0, 1fr) 42px;
    padding: 0 8px;
  }

  .dashboard-scene,
  .account-scene {
    grid-template-columns: 76px minmax(0, 1fr);
    min-height: 300px;
  }

  .mock-sidebar {
    padding: 10px 6px;
  }

  .mock-sidebar > span {
    overflow: hidden;
    padding: 6px;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .mock-sidebar .sidebar-brand {
    justify-content: center;
  }

  .sidebar-brand b {
    display: none;
  }

  .mock-workspace {
    padding: 18px 13px;
  }

  .redeem-panel,
  .subscription-panel {
    padding: 16px;
  }

  .subscription-meta {
    flex-direction: column;
    gap: 7px;
  }

  .finish-band {
    grid-template-columns: 38px minmax(0, 1fr);
    padding: 25px 22px;
  }

  .finish-check {
    width: 38px;
    height: 38px;
  }

  .finish-band > a {
    grid-column: 1 / -1;
    width: 100%;
  }

  .site-footer > div {
    flex-direction: column;
    gap: 2px;
    padding: 19px 0;
  }

  .back-to-top {
    right: 14px;
    bottom: 14px;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}