:root {
  --ink: #121212;
  --ink-soft: #242424;
  --paper: #f6f3ec;
  --paper-deep: #e9e2d5;
  --gold: #c99b42;
  --gold-light: #f0d28c;
  --coral: #e4503f;
  --teal: #2d7772;
  --white: #ffffff;
  --muted: #68645d;
  --line: #d8d0c2;
  --shadow: 8px 8px 0 rgba(18, 18, 18, 0.12);
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0;
}

body.nav-open {
  overflow: hidden;
}

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

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

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

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

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 200;
  padding: 8px 14px;
  color: var(--white);
  background: var(--ink);
  transform: translateY(-160%);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(18, 18, 18, 0.96);
  backdrop-filter: blur(12px);
}

.nav-wrap {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
  gap: 11px;
  color: var(--white);
  font-size: 20px;
  font-weight: 800;
}

.brand img {
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 6px;
}

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

.site-nav a {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  padding: 7px 14px;
  color: #ddd8cf;
  border-bottom: 2px solid transparent;
  font-size: 14px;
  font-weight: 700;
}

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

.site-nav .nav-download {
  margin-left: 8px;
  padding-inline: 18px;
  color: var(--ink);
  border: 1px solid var(--gold);
  border-radius: 4px;
  background: var(--gold-light);
}

.nav-toggle {
  width: 44px;
  height: 44px;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 0;
  color: var(--white);
  border: 1px solid #595959;
  border-radius: 4px;
  background: transparent;
  cursor: pointer;
}

.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  width: 20px;
  height: 2px;
  display: block;
  position: relative;
  background: currentColor;
}

.nav-toggle span::before,
.nav-toggle span::after {
  position: absolute;
  left: 0;
  content: "";
}

.nav-toggle span::before {
  top: -6px;
}

.nav-toggle span::after {
  top: 6px;
}

.hero {
  position: relative;
  overflow: hidden;
  color: var(--white);
  background: var(--ink);
}



.hero-grid {
  min-height: 620px;
  display: grid;
  position: relative;
  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
  align-items: center;
  gap: 64px;
  padding-block: 64px 50px;
}

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

.eyebrow {
  margin: 0 0 14px;
  color: var(--gold-light);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
}

.hero h1 {
  max-width: 670px;
  margin: 0;
  font-size: clamp(40px, 5vw, 72px);
  line-height: 1.08;
  letter-spacing: 0;
}

.hero-lead {
  max-width: 620px;
  margin: 24px 0 0;
  color: #d9d5ce;
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-top: 30px;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 11px 23px;
  border: 1px solid var(--ink);
  border-radius: 4px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.button:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 rgba(18, 18, 18, 0.25);
}

.button-primary {
  color: var(--ink);
  border-color: var(--gold-light);
  background: var(--gold-light);
}

.button-light {
  color: var(--white);
  border-color: #706f6a;
  background: transparent;
}

.button-coral {
  color: var(--white);
  border-color: var(--coral);
  background: var(--coral);
}

.version-note {
  color: #ada8a0;
  font-size: 13px;
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 34px 0 0;
  padding: 1px;
  background: #44413c;
}

.hero-facts div {
  min-height: 78px;
  padding: 12px 14px;
  background: var(--ink);
}

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

.hero-facts strong {
  color: var(--gold-light);
  font-size: 18px;
}

.hero-facts span {
  color: #b9b4aa;
  font-size: 12px;
}

.hero-visual {
  min-height: 500px;
  display: flex;
  position: relative;
  align-items: center;
  justify-content: center;
}

.phone-frame {
  width: min(290px, 80vw);
  position: relative;
  z-index: 2;
  padding: 10px;
  border: 2px solid #353535;
  border-radius: 30px;
  background: #080808;
  box-shadow: 20px 24px 0 rgba(18, 18, 18, 0.28);
}

.phone-frame::before {
  width: 74px;
  height: 5px;
  position: absolute;
  top: 12px;
  left: 50%;
  z-index: 4;
  border-radius: 4px;
  background: #202020;
  content: "";
  transform: translateX(-50%);
}

.phone-frame img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border-radius: 21px;
}

.visual-stamp {
  width: 118px;
  height: 118px;
  display: grid;
  position: absolute;
  right: 2%;
  bottom: 7%;
  z-index: 3;
  place-items: center;
  color: var(--ink);
  border: 4px solid var(--ink);
  border-radius: 50%;
  background: var(--gold-light);
  font-size: 15px;
  font-weight: 900;
  line-height: 1.25;
  text-align: center;
  transform: rotate(8deg);
}

.section {
  padding-block: 88px;
}

.section-tight {
  padding-block: 58px;
}

.section-dark {
  color: var(--white);
  background: var(--ink-soft);
}

.section-red {
  color: var(--white);
  background: var(--coral);
}

.section-gold {
  background: var(--gold-light);
}

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 30px;
  margin-bottom: 36px;
  padding-bottom: 17px;
  border-bottom: 2px solid currentColor;
}

.section-head h2 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.2;
  letter-spacing: 0;
}

.section-index {
  flex: 0 0 auto;
  font-size: 13px;
  font-weight: 900;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 18px;
}

.feature-item {
  min-height: 230px;
  position: relative;
  padding: 26px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--white);
}

.feature-item:nth-child(1),
.feature-item:nth-child(4) {
  grid-column: span 7;
}

.feature-item:nth-child(2),
.feature-item:nth-child(3) {
  grid-column: span 5;
}

.feature-number {
  position: absolute;
  top: 8px;
  right: 18px;
  color: var(--paper-deep);
  font-size: 68px;
  font-weight: 900;
  line-height: 1;
}

.feature-item h3 {
  position: relative;
  margin: 40px 0 12px;
  font-size: 23px;
}

.feature-item p {
  max-width: 520px;
  position: relative;
  margin: 0;
  color: var(--muted);
}

.preview-layout {
  display: grid;
  grid-template-columns: 0.75fr 1.25fr;
  align-items: center;
  gap: 70px;
}

.preview-copy h2 {
  margin: 0 0 24px;
  font-size: clamp(34px, 5vw, 58px);
  line-height: 1.15;
}

.preview-copy ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.preview-copy li {
  padding: 13px 0;
  border-bottom: 1px solid #484743;
  color: #d8d4cd;
}

.preview-copy li strong {
  display: block;
  color: var(--gold-light);
}

.preview-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  align-items: end;
  gap: 14px;
}

.preview-shot {
  margin: 0;
}

.preview-shot:nth-child(2) {
  transform: translateY(-28px);
}

.preview-shot img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border: 5px solid #0b0b0b;
  border-radius: 8px;
  box-shadow: 10px 10px 0 rgba(240, 210, 140, 0.18);
}

.preview-shot figcaption {
  margin-top: 10px;
  color: #bcb7ae;
  font-size: 12px;
  text-align: center;
}

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

.path-item {
  min-height: 255px;
  display: flex;
  flex-direction: column;
  padding: 26px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--paper);
  box-shadow: var(--shadow);
}

.path-item .path-kicker {
  color: var(--coral);
  font-size: 12px;
  font-weight: 900;
}

.path-item h3 {
  margin: 18px 0 10px;
  font-size: 24px;
}

.path-item p {
  margin: 0 0 26px;
  color: var(--muted);
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  font-weight: 900;
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 5px;
}

.text-link::after {
  content: "→";
}

.proof-band {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.proof-band div {
  min-height: 128px;
  padding: 23px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--white);
}

.proof-band strong,
.proof-band span {
  display: block;
}

.proof-band strong {
  font-size: 28px;
}

.proof-band span {
  color: var(--muted);
  font-size: 13px;
}

.review-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.review-item {
  margin: 0;
  padding: 26px;
  border-left: 4px solid var(--gold);
  background: #30302f;
}

.review-item blockquote {
  margin: 0 0 22px;
  color: #f2efe9;
}

.review-item figcaption {
  color: var(--gold-light);
  font-size: 13px;
}

.mini-faq {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px 30px;
}

.faq-item {
  border-top: 1px solid var(--line);
}

.faq-item summary {
  min-height: 66px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  cursor: pointer;
  font-weight: 800;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  flex: 0 0 auto;
  color: var(--coral);
  content: "+";
  font-size: 24px;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item p,
.faq-item ol,
.faq-item ul {
  margin-top: 0;
  padding-bottom: 20px;
  color: var(--muted);
}

.faq-item ol,
.faq-item ul {
  padding-left: 20px;
}

.download-band {
  color: var(--white);
  background: var(--ink);
}

.download-inner {
  min-height: 260px;
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 40px;
  padding-block: 48px;
}

.download-inner h2 {
  margin: 0 0 14px;
  font-size: clamp(32px, 5vw, 56px);
  line-height: 1.1;
}

.download-inner p {
  max-width: 700px;
  margin: 0;
  color: #c4c0b9;
}

.site-footer {
  color: #bdb8af;
  background: #090909;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 40px;
  padding-block: 44px 28px;
}

.footer-brand p {
  max-width: 620px;
  margin: 16px 0 0;
  font-size: 13px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: flex-end;
  gap: 18px;
  font-size: 13px;
}

.footer-links a:hover {
  color: var(--gold-light);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 30px;
  padding-block: 18px 30px;
  border-top: 1px solid #272727;
  font-size: 12px;
}

.footer-bottom p {
  margin: 0;
}

.subhero {
  position: relative;
  overflow: hidden;
  color: var(--white);
  background: var(--ink);
}

.subhero::after {
  width: 280px;
  height: 280px;
  position: absolute;
  right: 6%;
  bottom: -150px;
  border: 42px solid var(--gold);
  content: "";
  transform: rotate(18deg);
}

.subhero-inner {
  min-height: 390px;
  display: flex;
  position: relative;
  z-index: 1;
  flex-direction: column;
  justify-content: center;
  padding-block: 62px;
}

.breadcrumb {
  margin: 0 0 24px;
  color: var(--gold-light);
  font-size: 13px;
  font-weight: 800;
}

.breadcrumb a {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.subhero h1 {
  max-width: 820px;
  margin: 0;
  font-size: clamp(38px, 6vw, 68px);
  line-height: 1.12;
}

.subhero-lead {
  max-width: 730px;
  margin: 22px 0 0;
  color: #cec9c1;
  font-size: 18px;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  align-items: start;
  gap: 70px;
}

.article-body h2 {
  margin: 70px 0 24px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--ink);
  font-size: 34px;
  line-height: 1.25;
}

.article-body h2:first-child {
  margin-top: 0;
}

.article-body h3 {
  margin: 34px 0 12px;
  font-size: 22px;
}

.article-body p {
  margin: 0 0 18px;
  color: #403d38;
}

.article-body a {
  color: #a2392f;
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.article-body ul,
.article-body ol {
  margin: 0 0 24px;
  padding-left: 23px;
}

.article-body li {
  margin-bottom: 10px;
}

.article-aside {
  position: sticky;
  top: 104px;
}

.aside-block {
  margin-bottom: 20px;
  padding: 22px;
  border: 1px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
}

.aside-block h2,
.aside-block h3 {
  margin: 0 0 14px;
  font-size: 18px;
}

.aside-block ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.aside-block li + li {
  margin-top: 9px;
}

.aside-block a {
  color: var(--muted);
  font-size: 13px;
}

.aside-block a:hover {
  color: var(--coral);
}

.step-list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: guide-step;
}

.step-item {
  display: grid;
  grid-template-columns: 76px 1fr;
  gap: 22px;
  padding: 28px 0;
  border-top: 1px solid var(--line);
  counter-increment: guide-step;
}

.step-item::before {
  width: 62px;
  height: 62px;
  display: grid;
  place-items: center;
  color: var(--white);
  border-radius: 50%;
  background: var(--coral);
  content: counter(guide-step, decimal-leading-zero);
  font-size: 20px;
  font-weight: 900;
}

.step-item h3 {
  margin: 0 0 10px;
}

.step-item p:last-child {
  margin-bottom: 0;
}

.notice {
  margin: 28px 0;
  padding: 22px 24px;
  border-left: 5px solid var(--gold);
  background: #fff9e9;
}

.notice strong {
  display: block;
  margin-bottom: 6px;
}

.check-table {
  width: 100%;
  margin: 24px 0 34px;
  border-collapse: collapse;
  background: var(--white);
}

.check-table th,
.check-table td {
  padding: 14px 16px;
  border: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.check-table th {
  background: var(--paper-deep);
}

.screen-pair {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
  margin: 30px 0;
}

.screen-pair figure {
  margin: 0;
}

.screen-pair img {
  width: 100%;
  max-width: 400px;
  height: auto;
  margin: 0 auto;
  border: 6px solid var(--ink);
  border-radius: 8px;
}

.screen-pair figcaption {
  margin-top: 10px;
  color: var(--muted);
  font-size: 13px;
  text-align: center;
}

.faq-categories {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 40px;
}

.faq-categories a {
  padding: 8px 13px;
  border: 1px solid var(--ink);
  border-radius: 4px;
  background: var(--white);
  font-size: 13px;
  font-weight: 800;
}

.faq-group {
  scroll-margin-top: 100px;
}

.faq-group + .faq-group {
  margin-top: 64px;
}

.faq-group h2 {
  margin: 0 0 14px;
  font-size: 34px;
}

.faq-group .faq-item {
  background: var(--white);
}

.faq-group .faq-item summary,
.faq-group .faq-item p,
.faq-group .faq-item ul,
.faq-group .faq-item ol {
  padding-inline: 20px;
}

.related-links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.related-links a {
  min-height: 100px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 20px;
  border: 1px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  font-weight: 800;
}

.related-links a::after {
  content: "→";
  font-size: 24px;
}

@media (max-width: 980px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    position: fixed;
    top: 74px;
    right: 0;
    left: 0;
    flex-direction: column;
    align-items: stretch;
    padding: 20px;
    border-top: 1px solid #303030;
    background: var(--ink);
  }

  .site-nav.is-open {
    display: flex;
  }

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

  .site-nav .nav-download {
    margin: 8px 0 0;
  }

  .hero-grid,
  .preview-layout,
  .article-layout {
    grid-template-columns: 1fr;
  }

  .hero-grid {
    gap: 30px;
  }

  .hero::before {
    width: 100%;
    height: 34%;
    top: auto;
    bottom: 0;
  }

  .hero-copy {
    max-width: none;
  }

  .preview-copy {
    max-width: 720px;
  }

  .article-aside {
    position: static;
  }

  .path-grid,
  .review-grid {
    grid-template-columns: 1fr;
  }

  .proof-band {
    grid-template-columns: 1fr 1fr;
  }

  .article-aside {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
  }
}

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

  .section {
    padding-block: 64px;
  }

  .hero-grid {
    min-height: auto;
    padding-block: 48px 38px;
  }

  .hero h1 {
    font-size: 42px;
  }

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

  .hero-facts {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    min-height: 440px;
  }

  .visual-stamp {
    width: 96px;
    height: 96px;
    right: 0;
    font-size: 13px;
  }

  .feature-grid,
  .preview-strip,
  .mini-faq,
  .screen-pair,
  .related-links,
  .article-aside {
    grid-template-columns: 1fr;
  }

  .feature-item:nth-child(n) {
    grid-column: span 12;
  }

  .preview-strip {
    width: min(100%, 340px);
    margin: 0 auto;
  }

  .preview-shot:nth-child(2) {
    transform: none;
  }

  .section-head,
  .download-inner,
  .footer-grid,
  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
  }

  .section-head {
    display: flex;
  }

  .download-inner,
  .footer-grid {
    display: flex;
  }

  .footer-links {
    justify-content: flex-start;
  }

  .proof-band {
    grid-template-columns: 1fr;
  }

  .step-item {
    grid-template-columns: 52px 1fr;
    gap: 14px;
  }

  .step-item::before {
    width: 48px;
    height: 48px;
    font-size: 15px;
  }

  .check-table {
    display: block;
    overflow-x: auto;
  }

  .subhero-inner {
    min-height: 330px;
  }
}

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

  *,
  *::before,
  *::after {
    transition: none !important;
  }
}