:root {
  --paper: #f7f5ef;
  --surface: #ffffff;
  --ink: #17191d;
  --muted: #5f6570;
  --line: #cfd2d5;
  --red: #cf3b32;
  --red-dark: #9f261f;
  --cyan: #178e9d;
  --ochre: #c58a1c;
  --black: #101114;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
  line-height: 1.7;
  letter-spacing: 0;
}

body.menu-open {
  overflow: hidden;
}

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

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

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

.skip-link {
  position: fixed;
  left: 16px;
  top: -60px;
  z-index: 100;
  padding: 8px 12px;
  color: #fff;
  background: var(--black);
}

.skip-link:focus {
  top: 12px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  min-height: 68px;
  border-bottom: 1px solid var(--line);
  background: rgba(247, 245, 239, 0.97);
}

.header-inner {
  width: min(var(--max), calc(100% - 40px));
  min-height: 68px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  font-size: 17px;
  font-weight: 800;
}

.brand img {
  width: 38px;
  height: 38px;
  object-fit: cover;
  border: 1px solid var(--ink);
  border-radius: 4px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.site-nav a {
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 6px 14px;
  border-bottom: 2px solid transparent;
  font-size: 14px;
  font-weight: 700;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  border-color: var(--red);
}

.site-nav .nav-download,
.button-primary {
  color: #fff;
  border: 1px solid var(--red-dark);
  border-bottom-color: var(--red-dark);
  background: var(--red);
}

.site-nav .nav-download:hover {
  border-color: var(--black);
  background: var(--black);
}

.menu-toggle {
  width: 42px;
  height: 42px;
  padding: 9px;
  display: none;
  border: 1px solid var(--ink);
  border-radius: 4px;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
}

.container {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

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

.hero-inner {
  min-height: 620px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, 0.86fr);
  align-items: center;
  gap: 64px;
  padding: 34px 0;
}

.hero-kicker,
.eyebrow {
  margin: 0 0 14px;
  color: var(--red-dark);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
}

.hero-kicker span,
.eyebrow span {
  display: inline-block;
  margin-right: 10px;
  padding: 2px 8px;
  color: #fff;
  background: var(--black);
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 680px;
  margin-bottom: 18px;
  font-size: 54px;
  line-height: 1.08;
  font-weight: 900;
}

.h1-line {
  display: block;
}

.hero-copy > p:not(.hero-kicker) {
  max-width: 620px;
  margin-bottom: 22px;
  color: #444a53;
  font-size: 17px;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 22px;
  border: 1px solid var(--ink);
  border-radius: 4px;
  font-weight: 800;
}

.button-primary:hover {
  border-color: var(--black);
  background: var(--black);
}

.button-secondary {
  background: var(--surface);
}

.hero-ledger {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  max-width: 550px;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.hero-ledger div {
  min-width: 0;
  padding: 10px 12px;
  border-right: 1px solid var(--line);
}

.hero-ledger div:last-child {
  border-right: 0;
}

.hero-ledger strong,
.hero-ledger span {
  display: block;
}

.hero-ledger strong {
  font-size: 13px;
}

.hero-ledger span {
  color: var(--muted);
  font-size: 11px;
}

.archive-frame {
  position: relative;
  width: 344px;
  min-height: 542px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  background: var(--surface);
  box-shadow: 16px 16px 0 var(--cyan);
}

.archive-index {
  position: absolute;
  left: -30px;
  top: 22px;
  width: 58px;
  padding: 7px 5px;
  color: #fff;
  background: var(--red);
  text-align: center;
  font-size: 12px;
  font-weight: 900;
}

.archive-frame::after {
  content: "ACTIVE RECORD";
  position: absolute;
  right: -58px;
  bottom: 66px;
  padding: 6px 12px;
  color: var(--ink);
  background: var(--ochre);
  font-size: 10px;
  font-weight: 900;
  transform: rotate(90deg);
}

.archive-frame img {
  width: 274px;
  max-width: 400px;
  border: 6px solid var(--black);
  border-radius: 6px;
}

.section {
  padding: 76px 0;
}

.section-white {
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.section-dark {
  color: #fff;
  background: var(--black);
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 30px;
}

.section-heading h2 {
  margin: 0;
  font-size: 34px;
  line-height: 1.2;
}

.section-no {
  color: var(--red);
  font-size: 12px;
  font-weight: 900;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--ink);
  border-left: 1px solid var(--ink);
}

.feature-item {
  min-height: 220px;
  padding: 24px;
  border-right: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
  background: var(--paper);
}

.feature-item:nth-child(2) {
  background: #e9f5f5;
}

.feature-item:nth-child(4) {
  background: #f5e7e4;
}

.feature-item:nth-child(6) {
  background: #f4ecd7;
}

.feature-item .index {
  display: block;
  margin-bottom: 22px;
  color: var(--red-dark);
  font-size: 12px;
  font-weight: 900;
}

.feature-item h3 {
  margin-bottom: 8px;
  font-size: 20px;
}

.feature-item p {
  margin-bottom: 0;
  color: #4f555e;
  font-size: 14px;
}

.route-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 22px;
}

.route-card {
  min-height: 260px;
  padding: 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  border: 1px solid rgba(255, 255, 255, 0.45);
}

.route-card:first-child {
  background: var(--red-dark);
}

.route-card:last-child {
  color: var(--ink);
  background: var(--ochre);
}

.route-card .route-tag {
  font-size: 12px;
  font-weight: 900;
}

.route-card h3 {
  max-width: 430px;
  margin: 30px 0 14px;
  font-size: 28px;
  line-height: 1.25;
}

.route-card p {
  margin-bottom: 22px;
}

.route-card a {
  font-weight: 900;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.screen-record {
  padding: 14px;
  border: 1px solid var(--ink);
  background: var(--surface);
}

.screen-meta {
  min-height: 60px;
  display: grid;
  grid-template-columns: 42px 1fr;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid var(--line);
}

.screen-meta strong {
  color: var(--red);
  font-size: 12px;
}

.screen-meta span {
  font-size: 14px;
  font-weight: 800;
}

.screen-record img {
  width: min(100%, 314px);
  max-width: 400px;
  margin: 18px auto 0;
  border: 1px solid var(--black);
  border-radius: 6px;
}

.faq-preview {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 54px;
}

.faq-list {
  border-top: 1px solid var(--ink);
}

details {
  border-bottom: 1px solid var(--ink);
}

summary {
  position: relative;
  padding: 18px 42px 18px 0;
  cursor: pointer;
  font-weight: 800;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  content: "+";
  position: absolute;
  right: 4px;
  top: 15px;
  color: var(--red);
  font-size: 22px;
}

details[open] summary::after {
  content: "−";
}

details p {
  padding: 0 34px 18px 0;
  color: #4f555e;
}

.final-cta {
  padding: 64px 0;
  color: #fff;
  background: var(--cyan);
}

.cta-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 30px;
}

.cta-inner h2 {
  margin-bottom: 8px;
  font-size: 34px;
}

.cta-inner p,
.cta-note {
  margin-bottom: 0;
}

.cta-inner .button {
  min-width: 132px;
  color: #fff;
  border-color: #fff;
  background: var(--black);
}

.page-hero {
  padding: 70px 0 54px;
  border-bottom: 1px solid var(--ink);
  background: var(--surface);
}

.page-hero-inner {
  display: grid;
  grid-template-columns: 0.78fr 1.22fr;
  gap: 68px;
  align-items: end;
}

.page-hero h1 {
  margin-bottom: 0;
  font-size: 46px;
}

.page-hero p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 17px;
}

.content-layout {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 54px;
  padding: 64px 0 82px;
}

.content-aside {
  align-self: start;
  position: sticky;
  top: 94px;
  border-top: 3px solid var(--red);
}

.content-aside a {
  display: block;
  padding: 12px 4px;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  font-weight: 800;
}

.article-section {
  padding-bottom: 42px;
  margin-bottom: 42px;
  border-bottom: 1px solid var(--line);
}

.article-section:last-child {
  margin-bottom: 0;
}

.article-section h2 {
  margin-bottom: 20px;
  font-size: 30px;
  line-height: 1.3;
}

.article-section h3 {
  margin: 26px 0 8px;
  font-size: 19px;
}

.article-section p,
.article-section li {
  color: #414750;
}

.article-section ol,
.article-section ul {
  padding-left: 22px;
}

.note-box {
  margin: 24px 0;
  padding: 18px 20px;
  border-left: 5px solid var(--ochre);
  background: #f4ecd7;
}

.step-list {
  counter-reset: steps;
  display: grid;
  gap: 12px;
  padding: 0;
  list-style: none;
}

.step-list li {
  position: relative;
  min-height: 84px;
  padding: 16px 18px 16px 72px;
  border: 1px solid var(--line);
  background: var(--surface);
}

.step-list li::before {
  counter-increment: steps;
  content: counter(steps, decimal-leading-zero);
  position: absolute;
  left: 18px;
  top: 14px;
  color: var(--red);
  font-weight: 900;
}

.full-faq details p {
  max-width: 850px;
}

.site-footer {
  padding: 34px 0;
  color: #d9dbe0;
  background: var(--black);
  text-align: center;
}

.site-footer p {
  margin: 6px auto;
  max-width: 880px;
  font-size: 13px;
  text-align: center;
}

@media (max-width: 900px) {
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr) minmax(300px, 0.75fr);
    gap: 34px;
  }

  h1 {
    font-size: 46px;
  }

  .archive-frame {
    width: 310px;
    min-height: 516px;
  }

  .archive-frame img {
    width: 258px;
  }

  .page-hero-inner,
  .faq-preview {
    grid-template-columns: 1fr;
    gap: 22px;
  }

  .content-layout {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 34px;
  }
}

@media (max-width: 720px) {
  .header-inner,
  .container {
    width: min(100% - 28px, var(--max));
  }

  .site-header,
  .header-inner {
    min-height: 62px;
  }

  .menu-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    inset: 62px 0 auto 0;
    max-height: 0;
    overflow: hidden;
    display: block;
    border-bottom: 0;
    background: var(--paper);
    transition: max-height 180ms ease;
  }

  .site-nav.is-open {
    max-height: 320px;
    border-bottom: 1px solid var(--ink);
  }

  .site-nav a {
    width: 100%;
    min-height: 52px;
    justify-content: flex-start;
    padding: 8px 20px;
    border-bottom: 1px solid var(--line);
  }

  .site-nav .nav-download {
    justify-content: center;
  }

  .hero-inner {
    min-height: 0;
    grid-template-columns: 1fr;
    gap: 20px;
    padding: 24px 0 28px;
  }

  .hero-kicker {
    margin-bottom: 8px;
  }

  h1 {
    margin-bottom: 12px;
    font-size: 34px;
    line-height: 1.12;
  }

  .hero-copy > p:not(.hero-kicker) {
    margin-bottom: 14px;
    font-size: 14px;
    line-height: 1.65;
  }

  .hero-actions {
    margin-bottom: 14px;
  }

  .button {
    min-height: 42px;
    padding: 7px 18px;
  }

  .hero-ledger div {
    padding: 7px 8px;
  }

  .archive-frame {
    width: min(286px, calc(100% - 30px));
    min-height: 312px;
    box-shadow: 10px 10px 0 var(--cyan);
  }

  .archive-frame img {
    width: 190px;
    max-height: 338px;
    object-fit: contain;
  }

  .archive-index {
    left: -14px;
    top: 14px;
    width: 48px;
  }

  .archive-frame::after {
    right: -52px;
    bottom: 54px;
  }

  .section {
    padding: 54px 0;
  }

  .section-heading {
    margin-bottom: 22px;
  }

  .section-heading h2,
  .cta-inner h2 {
    font-size: 28px;
  }

  .feature-grid,
  .route-grid,
  .gallery-grid,
  .cta-inner,
  .content-layout {
    grid-template-columns: 1fr;
  }

  .feature-item {
    min-height: 0;
  }

  .route-card {
    min-height: 230px;
  }

  .gallery-grid {
    gap: 18px;
  }

  .screen-record img {
    width: 238px;
  }

  .cta-inner {
    justify-items: start;
  }

  .page-hero {
    padding: 42px 0 34px;
  }

  .page-hero h1 {
    font-size: 35px;
  }

  .page-hero p {
    font-size: 15px;
  }

  .content-layout {
    padding: 44px 0 62px;
  }

  .content-aside {
    position: static;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
  }

  .content-aside a {
    padding-right: 10px;
  }

  .article-section h2 {
    font-size: 26px;
  }
}

@media (max-width: 390px) {
  .brand {
    font-size: 16px;
  }

  .brand img {
    width: 34px;
    height: 34px;
  }

  .hero-ledger strong {
    font-size: 12px;
  }

  .hero-ledger span {
    display: none;
  }
}