:root {
  --ink: #163b39;
  --ink-deep: #102624;
  --coral: #ef5b49;
  --coral-dark: #c43d2f;
  --aqua: #20aa9e;
  --yellow: #f4c64f;
  --paper: #f7f8f4;
  --white: #ffffff;
  --muted: #667471;
  --line: #cdd8d4;
  --shadow: 7px 7px 0 #163b39;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--ink-deep);
  background: var(--paper);
  font-family: "Microsoft YaHei", "Segoe UI", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  opacity: 0.18;
  background-image: radial-gradient(#163b39 0.7px, transparent 0.7px);
  background-size: 18px 18px;
}

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

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

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

button,
input {
  font: inherit;
}

:focus-visible {
  outline: 3px solid var(--yellow);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 100;
  padding: 8px 14px;
  color: var(--white);
  background: var(--ink);
  transform: translateY(-150%);
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 2px solid var(--ink);
  background: rgba(247, 248, 244, 0.96);
  backdrop-filter: blur(12px);
}

.nav-wrap {
  position: relative;
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  font-weight: 900;
  font-size: 21px;
  color: var(--ink);
}

.brand img {
  width: 42px;
  height: 42px;
  border: 2px solid var(--ink);
  border-radius: 6px;
}

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

.site-nav > a:not(.download-btn) {
  padding: 10px 13px;
  border-bottom: 3px solid transparent;
  font-weight: 700;
}

.site-nav > a:not(.download-btn):hover,
.site-nav > a[aria-current="page"]:not(.download-btn) {
  color: var(--coral-dark);
  border-bottom-color: var(--coral);
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--ink);
  background: var(--white);
  cursor: pointer;
}

.menu-toggle span,
.menu-toggle::before,
.menu-toggle::after {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px 0;
  content: "";
  background: currentColor;
  transition: transform 180ms ease, opacity 180ms ease;
}

.menu-toggle[aria-expanded="true"] span {
  opacity: 0;
}

.menu-toggle[aria-expanded="true"]::before {
  transform: translateY(6px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"]::after {
  transform: translateY(-6px) rotate(-45deg);
}

.download-btn {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 11px 22px;
  border: 2px solid var(--ink-deep);
  border-radius: 6px;
  color: var(--white);
  background: var(--coral);
  box-shadow: 4px 4px 0 var(--ink-deep);
  font-weight: 900;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.download-btn:hover {
  background: var(--coral-dark);
  box-shadow: 2px 2px 0 var(--ink-deep);
  transform: translate(2px, 2px);
}

.download-btn.dark {
  color: var(--ink-deep);
  background: var(--yellow);
}

.eyebrow {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 10px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  color: var(--ink);
  background: var(--yellow);
  font-size: 13px;
  font-weight: 900;
}

.hero {
  position: relative;
  min-height: 685px;
  overflow: hidden;
  border-bottom: 3px solid var(--ink);
  background-color: #dff4ef;
}

.hero-inner {
  position: relative;
  z-index: 2;
  min-height: 575px;
  display: flex;
  align-items: center;
}

.hero-copy {
  min-width: 0;
  width: min(760px, 68%);
  padding: 58px 0;
}

.hero h1,
.page-hero h1 {
  max-width: 760px;
  margin: 0 0 20px;
  color: var(--ink-deep);
  font-size: clamp(38px, 5.3vw, 64px);
  line-height: 1.08;
  letter-spacing: 0;
}

.hero h1 span {
  color: var(--coral);
  text-decoration: underline;
  text-decoration-color: var(--yellow);
  text-decoration-thickness: 10px;
  text-underline-offset: -4px;
  text-decoration-skip-ink: none;
}

.hero-lead {
  max-width: 600px;
  margin: 0 0 28px;
  color: #395652;
  font-size: 19px;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 18px;
}

.hero-note {
  font-size: 14px;
  font-weight: 700;
  color: var(--muted);
}

.hero-shot {
  position: absolute;
  top: 38px;
  right: max(22vw, 24px);
  z-index: 1;
  width: min(31vw, 340px);
  max-width: 400px;
  height: auto;
  border-radius: 7px 7px 0 0;
  transform: rotate(2deg);
}

.quick-strip {
  border-bottom: 2px solid var(--ink);
  background: var(--ink);
  color: var(--white);
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.quick-item {
  min-width: 0;
  min-height: 92px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px;
  border-right: 1px solid #51716d;
}

.quick-item:last-child {
  border-right: 0;
}

.quick-icon,
.feature-index {
  display: grid;
  flex: 0 0 auto;
  place-items: center;
  width: 40px;
  height: 40px;
  border: 2px solid currentColor;
  border-radius: 50%;
  color: var(--yellow);
  font-weight: 900;
}

.quick-item strong {
  display: block;
  font-size: 16px;
}

.quick-item span:last-child {
  display: block;
  color: #bdd0cc;
  font-size: 13px;
}

.section {
  padding: 88px 0;
}

.section.alt {
  border-block: 2px solid var(--ink);
  background: var(--white);
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 38px;
}

.section h2,
.content-shell h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(29px, 4vw, 45px);
  line-height: 1.2;
  letter-spacing: 0;
}

.section-tag {
  color: var(--coral-dark);
  font-weight: 900;
  text-transform: uppercase;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 22px;
}

.feature-card {
  min-height: 220px;
  grid-column: span 4;
  padding: 26px;
  border: 2px solid var(--ink);
  border-radius: 7px;
  background: var(--white);
  box-shadow: var(--shadow);
}

.feature-card.wide {
  grid-column: span 8;
  background: #e4f6f2;
}

.feature-card.yellow {
  background: #fff3bf;
}

.feature-index {
  color: var(--ink);
  background: var(--coral);
}

.feature-card h3 {
  margin: 22px 0 8px;
  font-size: 23px;
  line-height: 1.3;
}

.feature-card p {
  margin: 0;
  color: #50635f;
}

.showcase-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 70px;
}

.device-stack {
  position: relative;
  min-height: 650px;
}

.device-stack img {
  position: absolute;
  width: min(72%, 360px);
  max-width: 400px;
  height: auto;
  border: 3px solid var(--ink);
  border-radius: 7px;
  box-shadow: 10px 10px 0 var(--yellow);
}

.device-stack img:first-child {
  top: 0;
  left: 0;
}

.device-stack img:last-child {
  right: 0;
  bottom: 0;
  z-index: 2;
  box-shadow: 10px 10px 0 var(--coral);
}

.showcase-copy h3 {
  margin: 0 0 15px;
  font-size: 31px;
  line-height: 1.25;
}

.plain-list {
  margin: 24px 0 30px;
  padding: 0;
  list-style: none;
}

.plain-list li {
  position: relative;
  margin: 12px 0;
  padding-left: 30px;
}

.plain-list li::before {
  position: absolute;
  top: 0;
  left: 0;
  color: var(--coral);
  content: "◆";
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--coral-dark);
  border-bottom: 2px solid currentColor;
  font-weight: 900;
}

.path-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.path-card {
  position: relative;
  min-height: 280px;
  padding: 28px;
  border-top: 8px solid var(--aqua);
  border-radius: 6px;
  background: var(--white);
  box-shadow: 0 0 0 2px var(--ink);
}

.path-card:nth-child(2) {
  border-top-color: var(--yellow);
}

.path-card:nth-child(3) {
  border-top-color: var(--coral);
}

.path-card .kicker {
  color: var(--muted);
  font-size: 13px;
  font-weight: 900;
}

.path-card h3 {
  margin: 10px 0;
  font-size: 25px;
}

.path-card p {
  margin-bottom: 28px;
}

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

.review {
  margin: 0;
  padding: 26px;
  border-left: 5px solid var(--coral);
  background: var(--white);
}

.review blockquote {
  margin: 0 0 20px;
  font-size: 17px;
}

.review figcaption {
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.rating-line {
  color: #d69400;
  letter-spacing: 2px;
}

.faq-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.faq-preview article {
  padding: 22px 0;
  border-top: 2px solid var(--ink);
}

.faq-preview h3 {
  margin: 0 0 8px;
  font-size: 19px;
}

.faq-preview p {
  margin: 0;
  color: var(--muted);
}

.cta-band {
  overflow: hidden;
  padding: 62px 0;
  border-block: 3px solid var(--ink-deep);
  color: var(--white);
  background-color: var(--aqua);
  background-image: repeating-linear-gradient(135deg, transparent 0 18px, rgba(16, 38, 36, 0.09) 18px 20px);
}

.cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.cta-band h2 {
  color: var(--white);
}

.cta-meta {
  margin: 8px 0 0;
  color: #e4fffa;
}

.mobile-break {
  display: none;
}

.page-hero {
  padding: 76px 0 62px;
  border-bottom: 3px solid var(--ink);
  background: #e4f6f2;
}

.page-hero h1 {
  font-size: clamp(36px, 6vw, 64px);
}

.page-hero p {
  max-width: 760px;
  margin: 0;
  color: #405d58;
  font-size: 18px;
}

.breadcrumb {
  display: flex;
  gap: 8px;
  margin-bottom: 22px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.breadcrumb a {
  color: var(--coral-dark);
}

.content-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 285px;
  align-items: start;
  gap: 48px;
}

.content-shell {
  min-width: 0;
}

.content-shell section {
  padding: 36px 0;
  border-bottom: 1px solid var(--line);
}

.content-shell section:first-child {
  padding-top: 0;
}

.content-shell h2 {
  margin-bottom: 22px;
  font-size: 32px;
}

.content-shell h3 {
  margin: 24px 0 8px;
  color: var(--ink);
  font-size: 21px;
}

.content-shell p {
  margin: 10px 0;
}

.side-index {
  position: sticky;
  top: 100px;
  padding: 22px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  box-shadow: 5px 5px 0 var(--yellow);
}

.side-index strong {
  display: block;
  margin-bottom: 12px;
  color: var(--ink);
}

.side-index a {
  display: block;
  padding: 8px 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.side-index a:hover {
  color: var(--coral-dark);
}

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

.step {
  position: relative;
  margin-bottom: 28px;
  padding: 26px 28px 26px 86px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  counter-increment: guide-step;
}

.step::before {
  position: absolute;
  top: 24px;
  left: 24px;
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border: 2px solid var(--ink);
  border-radius: 50%;
  color: var(--white);
  background: var(--coral);
  content: counter(guide-step, decimal-leading-zero);
  font-weight: 900;
}

.step h3 {
  margin-top: 0;
}

.notice {
  margin: 24px 0;
  padding: 18px 20px;
  border-left: 5px solid var(--yellow);
  background: #fff8d8;
}

.check-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.check-item {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--white);
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 18px 20px;
  border: 0;
  color: var(--ink-deep);
  background: transparent;
  text-align: left;
  cursor: pointer;
  font-weight: 900;
}

.faq-question::after {
  flex: 0 0 auto;
  color: var(--coral);
  content: "+";
  font-size: 26px;
  line-height: 1;
}

.faq-question[aria-expanded="true"]::after {
  content: "−";
}

.faq-answer {
  padding: 0 20px 18px;
  color: #4e615d;
}

.faq-answer[hidden] {
  display: none;
}

.feature-detail-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.feature-detail {
  padding: 22px;
  border: 1px solid var(--line);
  border-top: 5px solid var(--aqua);
  border-radius: 6px;
  background: var(--white);
}

.feature-detail h3 {
  margin-top: 0;
}

.related-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.related-links a {
  padding: 8px 13px;
  border: 2px solid var(--ink);
  border-radius: 5px;
  color: var(--ink);
  background: var(--white);
  font-weight: 800;
}

.site-footer {
  padding: 52px 0 28px;
  color: #d6e1df;
  background: var(--ink-deep);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 50px;
  padding-bottom: 34px;
}

.footer-brand .brand {
  color: var(--white);
}

.footer-brand p {
  max-width: 420px;
  color: #9fb4b0;
}

.footer-col strong {
  display: block;
  margin-bottom: 12px;
  color: var(--white);
}

.footer-col a {
  display: block;
  padding: 5px 0;
  color: #b9cbc7;
}

.footer-col a:hover {
  color: var(--yellow);
}

.disclaimer {
  padding: 20px 0;
  border-top: 1px solid #35514e;
  border-bottom: 1px solid #35514e;
  color: #9fb4b0;
  font-size: 13px;
}

.copyright {
  margin: 20px 0 0;
  color: #7f9994;
  font-size: 13px;
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 450ms ease, transform 450ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (max-width: 960px) {
  .menu-toggle {
    position: absolute;
    top: 11px;
    right: 0;
    display: block !important;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 2px);
    right: 20px;
    left: 20px;
    display: none;
    align-items: stretch;
    flex-direction: column;
    padding: 16px;
    border: 2px solid var(--ink);
    border-radius: 6px;
    background: var(--paper);
    box-shadow: 7px 7px 0 var(--ink);
  }

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

  .site-nav > a:not(.download-btn) {
    border-bottom: 1px solid var(--line);
  }

  .hero-copy {
    width: 68%;
  }

  .hero-shot {
    right: -60px;
    width: 38vw;
  }

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

  .quick-item:nth-child(2) {
    border-right: 0;
  }

  .quick-item:nth-child(-n+2) {
    border-bottom: 1px solid #51716d;
  }

  .feature-card,
  .feature-card.wide {
    grid-column: span 6;
  }

  .showcase-grid {
    gap: 36px;
  }

  .device-stack {
    min-height: 560px;
  }

  .content-layout {
    grid-template-columns: 1fr;
  }

  .side-index {
    position: static;
    order: -1;
  }
}

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

  .nav-wrap {
    min-height: 66px;
  }

  .brand {
    font-size: 19px;
  }

  .brand img {
    width: 38px;
    height: 38px;
  }

  .hero,
  .hero-inner {
    min-height: 690px;
  }

  .hero-inner {
    align-items: flex-start;
  }

  .hero-copy {
    z-index: 3;
    width: 100%;
    padding: 50px 0 320px;
  }

  .hero h1 {
    max-width: 520px;
    font-size: 39px;
    word-break: normal;
  }

  .mobile-break {
    display: block;
  }

  .hero-lead {
    max-width: 520px;
    font-size: 17px;
  }

  .hero-shot {
    top: auto;
    right: 14px;
    bottom: -120px;
    width: min(58vw, 290px);
    transform: rotate(1deg);
  }

  .section {
    padding: 64px 0;
  }

  .section-head {
    align-items: flex-start;
    flex-direction: column;
    margin-bottom: 28px;
  }

  .feature-grid,
  .showcase-grid,
  .path-grid,
  .review-grid,
  .faq-preview,
  .footer-grid,
  .feature-detail-grid,
  .check-grid {
    grid-template-columns: 1fr;
  }

  .feature-card,
  .feature-card.wide {
    grid-column: auto;
  }

  .showcase-grid {
    gap: 42px;
  }

  .device-stack {
    min-height: 610px;
  }

  .cta-inner {
    align-items: flex-start;
    flex-direction: column;
  }

  .page-hero {
    padding: 55px 0 46px;
  }

  .step {
    padding: 78px 20px 22px;
  }

  .step::before {
    top: 20px;
    left: 20px;
  }

  .footer-grid {
    gap: 28px;
  }
}

@media (max-width: 430px) {
  .quick-grid {
    grid-template-columns: 1fr;
  }

  .quick-item {
    border-right: 0;
    border-bottom: 1px solid #51716d;
  }

  .quick-item:last-child {
    border-bottom: 0;
  }

  .hero h1 {
    font-size: 35px;
    overflow-wrap: anywhere;
  }

  .hero-note {
    width: 100%;
  }

  .device-stack {
    min-height: 520px;
  }

  .device-stack img {
    width: 76%;
  }
}

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

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

  .reveal {
    opacity: 1;
    transform: none;
  }
}