:root {
  --wine: #7c3244;
  --wine-deep: #5d2634;
  --cyan: #2c7d86;
  --ink: #22282b;
  --soft-ink: #5f686c;
  --line: #d9ddde;
  --fog: #f3f5f5;
  --white: #ffffff;
  --shadow: 0 18px 46px rgba(49, 35, 39, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--white);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
  line-height: 1.72;
}

a {
  color: inherit;
  text-decoration: none;
}

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

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}

.topbar-rail,
.lead-rail,
.content-rail,
.manual-head-rail,
.manual-rail,
.answer-rail,
.bottom-rail {
  width: min(1160px, calc(100% - 48px));
  margin: 0 auto;
}

.topbar-rail {
  min-height: 70px;
  display: flex;
  align-items: center;
  gap: 28px;
}

.wordmark,
.bottom-name {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: var(--wine-deep);
  font-weight: 850;
}

.wordmark img,
.bottom-name img {
  border-radius: 5px;
}

.main-menu {
  display: flex;
  gap: 3px;
  margin-left: auto;
}

.main-menu a {
  padding: 7px 14px;
  border-top: 2px solid transparent;
  color: #505b60;
}

.main-menu a.current,
.main-menu a:hover {
  border-top-color: var(--wine);
  color: var(--wine-deep);
}

.topbar-downloads,
.lead-actions,
.closing-inner > div:last-child,
.manual-head nav,
.manual-download nav,
.answer-download nav {
  display: flex;
  gap: 9px;
  align-items: center;
}

.action {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 23px;
  border: 1px solid var(--wine);
  border-radius: 4px;
  background: var(--wine);
  color: #ffffff;
  font-weight: 800;
  line-height: 1;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.action:hover {
  background: var(--wine-deep);
  border-color: var(--wine-deep);
}

.action-compact {
  min-height: 37px;
  padding: 0 14px;
  font-size: 14px;
}

.action-quiet {
  background: transparent;
  color: var(--wine-deep);
}

.action-quiet:hover {
  color: #ffffff;
}

.nav-switch {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: #ffffff;
}

.nav-switch b {
  display: block;
  height: 2px;
  margin: 4px 0;
  background: var(--ink);
}

.lead {
  background: var(--fog);
  border-bottom: 1px solid var(--line);
}

.lead-rail {
  min-height: 594px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 460px;
  align-items: center;
  gap: 74px;
  padding: 48px 0 36px;
}

.kicker {
  display: block;
  margin-bottom: 13px;
  color: var(--wine);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0;
}

.lead h1,
.manual-head h1 {
  margin: 0;
  font-size: 50px;
  line-height: 1.14;
  letter-spacing: 0;
}

.lead-summary {
  max-width: 610px;
  margin: 22px 0 27px;
  color: var(--soft-ink);
  font-size: 17px;
}

.lead-points {
  display: grid;
  gap: 7px;
  margin: 24px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid #ccd2d3;
  list-style: none;
}

.lead-points li::before {
  content: "—";
  margin-right: 10px;
  color: var(--wine);
}

.lead-visual {
  display: grid;
  grid-template-columns: 275px 1fr;
  gap: 16px;
  align-items: center;
}

.screen-sheet {
  position: relative;
  padding: 12px 12px 15px;
  background: #ffffff;
  border: 1px solid #cfd4d5;
  border-radius: 4px;
  box-shadow: var(--shadow);
}

.screen-sheet img {
  width: 100%;
  max-width: 400px;
}

.sheet-tab {
  position: absolute;
  top: -12px;
  left: 14px;
  padding: 5px 12px;
  background: var(--wine);
  color: #ffffff;
  font-size: 12px;
  font-weight: 800;
}

.state-notes {
  display: grid;
  gap: 12px;
}

.state-notes > div {
  padding: 14px;
  background: #ffffff;
  border-left: 3px solid var(--cyan);
}

.state-notes strong,
.state-notes span {
  display: block;
}

.state-notes span {
  margin-top: 4px;
  color: var(--soft-ink);
  font-size: 13px;
}

.lead-caution {
  background: var(--wine-deep);
  color: #ffffff;
}

.lead-caution > div {
  width: min(1160px, calc(100% - 48px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 20px;
  padding: 18px 0;
}

.lead-caution span {
  color: #f1dce2;
}

.fold {
  padding: 76px 0;
}

.fold-mist {
  background: var(--fog);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.fold-title {
  display: flex;
  align-items: baseline;
  gap: 18px;
  margin-bottom: 32px;
}

.fold-title span {
  color: var(--wine);
  font-weight: 900;
}

.fold-title h2,
.permission-copy h2,
.closing h2,
.manual-download h2,
.answer-download h2 {
  margin: 0;
  font-size: 34px;
  line-height: 1.25;
}

.advantage-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.advantage-row article {
  padding: 25px 30px;
  border-right: 1px solid var(--line);
}

.advantage-row article:last-child {
  border-right: 0;
}

.advantage-row h3 {
  margin: 0 0 8px;
  font-size: 19px;
}

.advantage-row article > div {
  color: var(--soft-ink);
}

.step-axis {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 3px solid var(--wine);
}

.step-axis article {
  position: relative;
  padding: 24px 22px 20px 0;
}

.step-axis article::before {
  content: "";
  position: absolute;
  width: 10px;
  height: 10px;
  top: -7px;
  left: 0;
  border: 2px solid var(--wine);
  border-radius: 50%;
  background: var(--fog);
}

.step-axis b,
.step-axis span {
  display: block;
}

.step-axis span {
  margin-top: 7px;
  color: var(--soft-ink);
}

.inline-link,
.light-link {
  display: inline-block;
  margin-top: 22px;
  color: var(--wine-deep);
  font-weight: 850;
  border-bottom: 1px solid currentColor;
}

.interface-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}

.interface-strip figure {
  margin: 0;
  padding: 20px;
  background: var(--fog);
  border: 1px solid var(--line);
}

.interface-strip img {
  max-width: 400px;
  max-height: 450px;
  width: auto;
  margin: 0 auto;
}

.interface-strip figcaption {
  display: grid;
  gap: 3px;
  padding-top: 16px;
}

.interface-strip figcaption span {
  color: var(--soft-ink);
  font-size: 14px;
}

.permission-band {
  padding: 74px 0;
  background: #26393d;
  color: #ffffff;
}

.permission-layout {
  display: grid;
  grid-template-columns: 390px 1fr;
  align-items: center;
  gap: 80px;
}

.permission-image {
  display: flex;
  justify-content: center;
}

.permission-image img {
  max-width: 310px;
  border: 9px solid #ffffff;
  box-shadow: var(--shadow);
}

.kicker-light {
  color: #7ad0d7;
}

.permission-intro {
  max-width: 650px;
  margin: 20px 0;
  color: #d4e0e2;
  font-size: 17px;
}

.permission-copy ul {
  margin: 0;
  padding-left: 20px;
  color: #edf3f4;
}

.light-link {
  color: #91d9df;
}

.question-preview {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 64px;
}

.question-links {
  border-top: 1px solid var(--line);
}

.question-links a {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 19px 0;
  border-bottom: 1px solid var(--line);
}

.question-links b {
  color: var(--wine);
}

.closing {
  padding: 50px 0;
  background: var(--wine);
  color: #ffffff;
}

.closing-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.closing-inner span {
  color: #f0ced7;
  font-size: 13px;
  font-weight: 800;
}

.closing h2 {
  margin-top: 6px;
  font-size: 28px;
}

.action-light {
  background: #ffffff;
  border-color: #ffffff;
  color: var(--wine-deep);
}

.action-outline {
  background: transparent;
  border-color: #ffffff;
}

.bottom {
  padding: 44px 0;
  background: #1f282b;
  color: #cbd3d5;
}

.bottom-rail {
  text-align: center;
}

.bottom-name {
  color: #ffffff;
}

.bottom-links {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 20px 0;
}

.bottom p {
  max-width: 760px;
  margin: 0 auto 8px;
  text-align: center;
  font-size: 13px;
}

.bottom small {
  display: block;
  text-align: center;
}

.manual-head {
  background: var(--fog);
  border-bottom: 1px solid var(--line);
}

.manual-head-rail {
  min-height: 360px;
  display: grid;
  align-content: center;
  padding: 50px 0;
}

.manual-head h1 {
  font-size: 43px;
}

.manual-head-rail > div {
  max-width: 720px;
  margin-top: 17px;
  color: var(--soft-ink);
  font-size: 17px;
}

.manual-head nav {
  margin-top: 24px;
}

.manual-body,
.answer-area {
  padding: 66px 0 88px;
}

.manual-rail {
  display: grid;
  grid-template-columns: 190px minmax(0, 820px);
  justify-content: space-between;
  gap: 66px;
  align-items: start;
}

.manual-tabs {
  position: sticky;
  top: 96px;
  display: grid;
  border-top: 3px solid var(--wine);
}

.manual-tabs a {
  padding: 12px 2px;
  border-bottom: 1px solid var(--line);
  color: var(--soft-ink);
}

.manual-pages,
.answer-list {
  min-width: 0;
}

.manual-pages article {
  padding: 0 0 50px;
  margin-bottom: 45px;
  border-bottom: 1px solid var(--line);
}

.manual-pages header {
  display: grid;
  grid-template-columns: 90px 1fr;
  align-items: baseline;
  margin-bottom: 17px;
}

.manual-pages header span {
  color: var(--wine);
  font-size: 12px;
  font-weight: 900;
}

.manual-pages h2 {
  margin: 0;
  font-size: 28px;
}

.manual-pages p {
  margin: 0 0 16px 90px;
  color: #465156;
}

.manual-pages p a {
  color: var(--wine);
  font-weight: 800;
  border-bottom: 1px solid currentColor;
}

.manual-note {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 16px;
  margin: 20px 0 0 90px;
  padding: 18px;
  background: #f6edef;
  border-left: 3px solid var(--wine);
}

.manual-pages figure {
  max-width: 350px;
  margin: 24px 0 0 90px;
  padding: 17px;
  background: var(--fog);
  border: 1px solid var(--line);
}

.manual-pages figure img {
  max-width: 400px;
  margin: 0 auto;
}

.manual-pages figcaption {
  margin-top: 11px;
  color: var(--soft-ink);
  font-size: 13px;
}

.manual-download,
.answer-download {
  padding: 28px;
  background: var(--fog);
  border: 1px solid var(--line);
}

.manual-download h2,
.answer-download h2 {
  font-size: 25px;
}

.manual-download > div,
.answer-download > div {
  margin: 8px 0 20px;
  color: var(--soft-ink);
}

.answer-rail {
  max-width: 940px;
}

.answer-intro {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 20px;
  margin-bottom: 34px;
  padding: 20px 0;
  border-top: 3px solid var(--wine);
  border-bottom: 1px solid var(--line);
}

.answer-intro span {
  color: var(--soft-ink);
}

.answer-list details {
  border-bottom: 1px solid var(--line);
}

.answer-list details:first-child {
  border-top: 1px solid var(--line);
}

.answer-list summary {
  display: grid;
  grid-template-columns: 58px 1fr;
  gap: 18px;
  padding: 21px 0;
  font-size: 17px;
  font-weight: 800;
  cursor: pointer;
  list-style: none;
}

.answer-list summary::-webkit-details-marker {
  display: none;
}

.answer-list summary span {
  color: var(--wine);
}

.answer-list details > div {
  padding: 0 0 23px 76px;
  color: var(--soft-ink);
}

.answer-download {
  margin-top: 44px;
}

@media (max-width: 980px) {
  .topbar-downloads {
    display: none;
  }

  .lead-rail {
    grid-template-columns: minmax(0, 1fr) 400px;
    gap: 38px;
  }

  .lead-visual {
    grid-template-columns: 240px 1fr;
  }
}

@media (max-width: 780px) {
  .topbar-rail,
  .lead-rail,
  .content-rail,
  .manual-head-rail,
  .manual-rail,
  .answer-rail,
  .bottom-rail,
  .lead-caution > div {
    width: calc(100% - 32px);
    max-width: 660px;
  }

  .topbar-rail {
    min-height: 64px;
  }

  .nav-switch {
    display: block;
    margin-left: auto;
  }

  .main-menu {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 63px;
    display: none;
    padding: 10px;
    background: #ffffff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
  }

  .main-menu.open {
    display: grid;
  }

  .lead-rail {
    min-height: auto;
    grid-template-columns: 1fr;
    gap: 22px;
    padding: 34px 0 22px;
  }

  .lead h1 {
    font-size: 39px;
  }

  .lead-visual {
    grid-template-columns: 230px 1fr;
    width: min(100%, 470px);
    margin: 0 auto;
  }

  .lead-caution > div {
    grid-template-columns: 1fr;
    gap: 3px;
  }

  .advantage-row,
  .interface-strip {
    grid-template-columns: 1fr;
  }

  .advantage-row article {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .step-axis {
    grid-template-columns: 1fr 1fr;
  }

  .permission-layout,
  .question-preview,
  .manual-rail {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .permission-image img {
    max-height: 410px;
    width: auto;
  }

  .closing-inner {
    display: grid;
  }

  .manual-tabs {
    position: static;
    grid-template-columns: repeat(5, auto);
    overflow-x: auto;
  }
}

@media (max-width: 520px) {
  .wordmark img {
    width: 42px;
    height: 42px;
  }

  .lead-rail {
    gap: 11px;
    padding: 26px 0 16px;
  }

  .kicker {
    margin-bottom: 7px;
  }

  .lead h1,
  .manual-head h1 {
    font-size: 32px;
  }

  .lead-summary {
    margin: 12px 0 16px;
    font-size: 15px;
    line-height: 1.58;
  }

  .lead-actions,
  .manual-head nav,
  .manual-download nav,
  .answer-download nav,
  .closing-inner > div:last-child {
    width: 100%;
    align-items: stretch;
  }

  .lead-actions .action,
  .manual-head nav .action,
  .manual-download .action,
  .answer-download .action,
  .closing-inner .action {
    flex: 1;
    padding: 0 12px;
  }

  .lead-points {
    gap: 2px;
    margin-top: 14px;
    padding-top: 10px;
    font-size: 14px;
  }

  .lead-visual {
    grid-template-columns: 132px 1fr;
    gap: 10px;
    width: 100%;
  }

  .screen-sheet {
    padding: 7px;
  }

  .state-notes {
    gap: 7px;
  }

  .state-notes > div {
    padding: 9px;
  }

  .sheet-tab {
    top: -8px;
    left: 8px;
    padding: 3px 7px;
    font-size: 10px;
  }

  .lead-caution > div {
    padding: 11px 0;
    font-size: 13px;
  }

  .fold,
  .permission-band {
    padding: 56px 0;
  }

  .fold-title h2,
  .permission-copy h2 {
    font-size: 28px;
  }

  .step-axis {
    grid-template-columns: 1fr;
  }

  .step-axis article {
    padding-right: 0;
  }

  .interface-strip img {
    max-height: 510px;
  }

  .manual-head-rail {
    min-height: 0;
    padding: 40px 0;
  }

  .manual-head-rail > div {
    font-size: 15px;
  }

  .manual-body,
  .answer-area {
    padding: 46px 0 64px;
  }

  .manual-tabs {
    grid-template-columns: 1fr 1fr;
  }

  .manual-pages header {
    grid-template-columns: 1fr;
    gap: 5px;
  }

  .manual-pages p,
  .manual-note,
  .manual-pages figure {
    margin-left: 0;
  }

  .manual-note,
  .answer-intro {
    grid-template-columns: 1fr;
  }

  .answer-list summary {
    grid-template-columns: 40px 1fr;
    gap: 10px;
  }

  .answer-list details > div {
    padding-left: 50px;
  }

  .bottom-links {
    flex-wrap: wrap;
    gap: 10px 20px;
  }
}