:root {
  --ink: #19191c;
  --paper: #faf7f1;
  --white: #ffffff;
  --coral: #f2554a;
  --yellow: #f3c84b;
  --teal: #1fae9a;
  --muted: #6b6865;
  --line: #d9d2c8;
  --shadow: 8px 8px 0 var(--ink);
  --content: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.75;
}

body.nav-open {
  overflow: hidden;
}

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

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

button,
input {
  font: inherit;
}

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

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 100;
  padding: 8px 12px;
  background: var(--ink);
  color: var(--white);
  transform: translateY(-140%);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 3px solid var(--ink);
  background: rgba(250, 247, 241, 0.96);
}

.nav-wrap {
  width: min(var(--content), calc(100% - 40px));
  min-height: 74px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 1.35rem;
  letter-spacing: 0;
}

.brand img {
  width: 46px;
  height: 46px;
  border: 2px solid var(--ink);
}

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

.main-nav a {
  min-height: 42px;
  padding: 8px 14px;
  display: inline-flex;
  align-items: center;
  border-bottom: 3px solid transparent;
  font-weight: 700;
}

.main-nav a:hover,
.main-nav a:focus-visible,
.main-nav a[aria-current="page"] {
  border-color: var(--coral);
}

.main-nav .nav-download {
  margin-left: 8px;
  padding-inline: 18px;
  border: 2px solid var(--ink);
  background: var(--coral);
  color: var(--white);
  box-shadow: 4px 4px 0 var(--ink);
}

.main-nav .nav-download:hover,
.main-nav .nav-download:focus-visible {
  border-color: var(--ink);
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--ink);
}

.nav-toggle {
  width: 44px;
  height: 44px;
  display: none;
  place-items: center;
  padding: 0;
  border: 2px solid var(--ink);
  background: var(--yellow);
  cursor: pointer;
}

.nav-toggle span,
.nav-toggle::before,
.nav-toggle::after {
  width: 22px;
  height: 3px;
  display: block;
  background: var(--ink);
  content: "";
}

.nav-toggle span {
  margin: 4px 0;
}

.hero {
  min-height: 650px;
  display: grid;
  align-items: center;
  border-bottom: 3px solid var(--ink);
  overflow: hidden;
}

.hero-grid {
  width: min(var(--content), calc(100% - 40px));
  margin: 0 auto;
  padding: 68px 0 76px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: 72px;
}

.eyebrow {
  width: fit-content;
  margin: 0 0 18px;
  padding: 4px 11px;
  border: 2px solid var(--ink);
  background: var(--yellow);
  font-size: 0.85rem;
  font-weight: 900;
}

h1,
h2,
h3 {
  margin-top: 0;
  line-height: 1.2;
  letter-spacing: 0;
}

h1 {
  max-width: 680px;
  margin-bottom: 20px;
  font-size: clamp(3rem, 7vw, 6.4rem);
  font-weight: 900;
}

.hero h1 .accent {
  color: var(--coral);
  text-shadow: 4px 4px 0 var(--ink);
  -webkit-text-stroke: 2px var(--ink);
}

.hero-copy > p:not(.eyebrow) {
  max-width: 650px;
  margin: 0;
  font-size: 1.12rem;
  color: #454346;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
}

.button {
  min-height: 50px;
  padding: 11px 22px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 3px solid var(--ink);
  background: var(--coral);
  color: var(--white);
  box-shadow: 5px 5px 0 var(--ink);
  font-weight: 900;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translate(3px, 3px);
  box-shadow: 2px 2px 0 var(--ink);
}

.button.secondary {
  background: var(--white);
  color: var(--ink);
}

.button.yellow {
  background: var(--yellow);
  color: var(--ink);
}

.button.teal {
  background: var(--teal);
}

.quick-facts {
  margin: 30px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
  list-style: none;
}

.quick-facts li {
  position: relative;
  padding-left: 18px;
  font-weight: 700;
}

.quick-facts li::before {
  position: absolute;
  top: 0.62em;
  left: 0;
  width: 9px;
  height: 9px;
  background: var(--teal);
  border: 2px solid var(--ink);
  content: "";
  transform: rotate(45deg);
}

.hero-visual {
  position: relative;
  min-height: 520px;
}

.phone-panel {
  position: absolute;
  top: 4px;
  left: 50%;
  z-index: 2;
  width: 278px;
  padding: 12px;
  border: 4px solid var(--ink);
  background: var(--white);
  box-shadow: 12px 12px 0 var(--coral);
  transform: translateX(-50%) rotate(2deg);
}

.phone-panel img {
  width: 100%;
  max-width: 400px;
  height: auto;
}

.burst {
  position: absolute;
  z-index: 3;
  padding: 10px 14px;
  border: 3px solid var(--ink);
  background: var(--yellow);
  box-shadow: 4px 4px 0 var(--ink);
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 1.3rem;
  font-weight: 900;
  transform: rotate(-7deg);
}

.burst.one {
  top: 52px;
  right: 0;
}

.burst.two {
  bottom: 40px;
  left: 0;
  background: var(--teal);
  color: var(--white);
  transform: rotate(5deg);
}

.hero-visual::before,
.hero-visual::after {
  position: absolute;
  content: "";
}

.hero-visual::before {
  inset: 38px 12px 0;
  background-image: radial-gradient(var(--ink) 1.5px, transparent 1.5px);
  background-size: 14px 14px;
  opacity: 0.18;
}

.hero-visual::after {
  right: -40px;
  bottom: -18px;
  width: 220px;
  height: 90px;
  border: 4px solid var(--ink);
  background: var(--yellow);
  transform: rotate(-8deg);
}

.section {
  padding: 90px 0;
  border-bottom: 2px solid var(--ink);
}

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

.section-heading {
  margin-bottom: 42px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
}

.section-heading h2 {
  margin-bottom: 0;
  font-size: clamp(2rem, 5vw, 3.8rem);
  font-weight: 900;
}

.section-number {
  color: var(--coral);
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 1.4rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.feature-item {
  min-height: 250px;
  padding: 26px 24px;
  border: 3px solid var(--ink);
  background: var(--white);
  box-shadow: 6px 6px 0 var(--ink);
}

.feature-item:nth-child(2) {
  background: var(--yellow);
}

.feature-item:nth-child(3) {
  background: var(--teal);
  color: var(--white);
}

.feature-item:nth-child(4) {
  background: var(--coral);
  color: var(--white);
}

.feature-mark {
  width: 48px;
  height: 48px;
  margin-bottom: 34px;
  display: grid;
  place-items: center;
  border: 3px solid currentColor;
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 1.1rem;
}

.feature-item h3 {
  margin-bottom: 10px;
  font-size: 1.25rem;
}

.feature-item p {
  margin: 0;
}

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

.showcase .section-heading h2 {
  color: var(--white);
}

.screenshot-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  align-items: start;
  gap: 24px;
}

.screenshot {
  margin: 0;
}

.screenshot:nth-child(even) {
  margin-top: 44px;
}

.screenshot button {
  width: 100%;
  padding: 8px;
  border: 3px solid var(--white);
  background: var(--white);
  cursor: zoom-in;
}

.screenshot img {
  width: 100%;
  max-width: 400px;
  height: auto;
  margin: 0 auto;
}

.screenshot figcaption {
  margin-top: 12px;
  color: #d8d3cc;
  font-size: 0.92rem;
}

.path-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 70px;
}

.path-intro h2 {
  font-size: clamp(2.2rem, 5vw, 4rem);
}

.path-intro p {
  margin: 0 0 24px;
  color: var(--muted);
}

.path-links {
  display: grid;
  gap: 0;
  border-top: 3px solid var(--ink);
}

.path-link {
  min-height: 150px;
  padding: 28px 10px;
  display: grid;
  grid-template-columns: 70px 1fr auto;
  align-items: center;
  gap: 24px;
  border-bottom: 3px solid var(--ink);
}

.path-link:hover,
.path-link:focus-visible {
  background: var(--yellow);
}

.path-link .index {
  color: var(--coral);
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 2rem;
}

.path-link h3 {
  margin-bottom: 7px;
  font-size: 1.45rem;
}

.path-link p {
  margin: 0;
  color: var(--muted);
}

.path-link .arrow {
  font-size: 2rem;
  font-weight: 900;
}

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

.quote {
  margin: 0;
  padding: 26px;
  border: 3px solid var(--ink);
  background: var(--white);
}

.quote:nth-child(2) {
  background: var(--yellow);
}

.quote blockquote {
  margin: 0 0 22px;
  font-size: 1.05rem;
  font-weight: 700;
}

.quote cite {
  color: var(--muted);
  font-style: normal;
}

.faq-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.faq-preview article {
  padding: 24px 0;
  border-top: 3px solid var(--ink);
}

.faq-preview h3 {
  margin-bottom: 8px;
  font-size: 1.1rem;
}

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

.download-band {
  padding: 70px 0;
  border-bottom: 3px solid var(--ink);
  background: var(--yellow);
}

.download-band-inner {
  width: min(var(--content), calc(100% - 40px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.download-band h2 {
  margin-bottom: 8px;
  font-size: clamp(2rem, 5vw, 4rem);
}

.download-band p {
  max-width: 720px;
  margin: 0;
}

.page-hero {
  padding: 90px 0 72px;
  border-bottom: 3px solid var(--ink);
}

.page-hero .section-inner {
  display: grid;
  grid-template-columns: 1fr 0.42fr;
  align-items: end;
  gap: 70px;
}

.page-hero h1 {
  max-width: 920px;
  margin-bottom: 20px;
  font-size: clamp(2.7rem, 7vw, 5.5rem);
}

.page-hero p {
  max-width: 750px;
  margin: 0;
  color: #484548;
  font-size: 1.08rem;
}

.page-stamp {
  min-height: 180px;
  display: grid;
  place-items: center;
  border: 4px solid var(--ink);
  background: var(--teal);
  color: var(--white);
  box-shadow: var(--shadow);
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 3rem;
  text-align: center;
  transform: rotate(3deg);
}

.steps {
  counter-reset: step;
}

.step {
  padding: 52px 0;
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr) minmax(260px, 0.55fr);
  gap: 42px;
  border-bottom: 2px solid var(--line);
  counter-increment: step;
}

.step::before {
  color: var(--coral);
  font-family: Impact, "Arial Black", sans-serif;
  font-size: 4rem;
  content: "0" counter(step);
}

.step h2 {
  margin-bottom: 14px;
  font-size: 2rem;
}

.step p {
  margin: 0 0 14px;
}

.step ul {
  margin: 18px 0 0;
  padding-left: 1.2em;
}

.step-aside {
  align-self: start;
  padding: 22px;
  border: 3px solid var(--ink);
  background: var(--white);
  box-shadow: 5px 5px 0 var(--ink);
}

.step-aside strong {
  display: block;
  margin-bottom: 8px;
}

.step-aside p {
  margin: 0;
  color: var(--muted);
}

.step-aside img {
  width: 100%;
  max-width: 300px;
  height: auto;
  margin: 0 auto 14px;
}

.safety-strip {
  background: var(--teal);
  color: var(--white);
}

.check-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.check-item {
  border-top: 3px solid var(--white);
  padding-top: 18px;
}

.check-item h3 {
  margin-bottom: 8px;
}

.check-item p {
  margin: 0;
}

.feature-manual {
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr);
  gap: 60px;
}

.manual-nav {
  position: sticky;
  top: 105px;
  align-self: start;
  border-top: 3px solid var(--ink);
}

.manual-nav a {
  padding: 14px 4px;
  display: block;
  border-bottom: 2px solid var(--ink);
  font-weight: 800;
}

.manual-nav a:hover,
.manual-nav a:focus-visible {
  color: var(--coral);
}

.manual-content > section {
  padding: 0 0 50px;
  scroll-margin-top: 110px;
}

.manual-content h2 {
  margin-bottom: 18px;
  font-size: 2.15rem;
}

.manual-content p {
  margin: 0 0 16px;
}

.manual-points {
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  list-style: none;
}

.manual-points li {
  padding: 16px;
  border: 2px solid var(--ink);
  background: var(--white);
}

.faq-list {
  border-top: 3px solid var(--ink);
}

.faq-item {
  border-bottom: 2px solid var(--ink);
}

.faq-question {
  width: 100%;
  padding: 22px 4px;
  display: grid;
  grid-template-columns: 1fr 34px;
  align-items: center;
  gap: 20px;
  border: 0;
  background: transparent;
  color: var(--ink);
  text-align: left;
  font-weight: 900;
  cursor: pointer;
}

.faq-question::after {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  border: 2px solid var(--ink);
  background: var(--yellow);
  content: "+";
  font-size: 1.3rem;
}

.faq-question[aria-expanded="true"]::after {
  background: var(--coral);
  color: var(--white);
  content: "-";
}

.faq-answer {
  max-width: 900px;
  padding: 0 56px 24px 4px;
  color: var(--muted);
}

.faq-answer p {
  margin: 0;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 90;
  display: none;
  place-items: center;
  padding: 30px;
  background: rgba(25, 25, 28, 0.92);
}

.lightbox.open {
  display: grid;
}

.lightbox img {
  max-width: min(400px, 85vw);
  max-height: 82vh;
  width: auto;
  height: auto;
  border: 4px solid var(--white);
}

.lightbox-close {
  position: absolute;
  top: 24px;
  right: 24px;
  width: 48px;
  height: 48px;
  border: 3px solid var(--white);
  background: var(--coral);
  color: var(--white);
  cursor: pointer;
  font-size: 1.5rem;
  font-weight: 900;
}

.site-footer {
  padding: 54px 0 28px;
  background: var(--ink);
  color: var(--white);
}

.footer-grid {
  width: min(var(--content), calc(100% - 40px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 50px;
}

.site-footer .brand {
  margin-bottom: 16px;
}

.site-footer .brand img {
  background: var(--paper);
}

.site-footer p {
  max-width: 760px;
  margin: 0;
  color: #c9c5bf;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  align-content: start;
  gap: 10px 22px;
}

.footer-links a {
  border-bottom: 1px solid transparent;
}

.footer-links a:hover,
.footer-links a:focus-visible {
  border-color: var(--yellow);
  color: var(--yellow);
}

.copyright {
  width: min(var(--content), calc(100% - 40px));
  margin: 36px auto 0;
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid #4e4c4c;
  color: #aaa6a1;
  font-size: 0.86rem;
}

:focus-visible {
  outline: 3px solid var(--teal);
  outline-offset: 4px;
}

@media (max-width: 980px) {
  .feature-grid,
  .screenshot-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero-grid {
    grid-template-columns: 1fr 0.75fr;
    gap: 38px;
  }

  .path-grid {
    gap: 35px;
  }

  .step {
    grid-template-columns: 85px 1fr;
  }

  .step-aside {
    grid-column: 2;
  }

  .feature-manual {
    grid-template-columns: 190px 1fr;
    gap: 36px;
  }
}

@media (max-width: 760px) {
  .nav-wrap {
    min-height: 66px;
  }

  .nav-toggle {
    display: grid;
  }

  .main-nav {
    position: fixed;
    inset: 66px 0 0;
    display: none;
    align-content: start;
    padding: 26px 20px;
    background: var(--paper);
  }

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

  .main-nav a {
    min-height: 56px;
    padding: 12px 4px;
    border-bottom: 2px solid var(--ink);
  }

  .main-nav .nav-download {
    margin: 18px 0 0;
    justify-content: center;
  }

  .hero {
    min-height: auto;
  }

  .hero-grid {
    padding: 52px 0 58px;
    grid-template-columns: 1fr;
  }

  h1 {
    font-size: clamp(2.8rem, 16vw, 4.6rem);
  }

  .hero-visual {
    min-height: 500px;
  }

  .phone-panel {
    width: 260px;
  }

  .section {
    padding: 66px 0;
  }

  .section-heading {
    margin-bottom: 30px;
    align-items: start;
  }

  .feature-grid,
  .screenshot-grid,
  .path-grid,
  .voices-grid,
  .faq-preview,
  .check-grid,
  .footer-grid,
  .page-hero .section-inner,
  .feature-manual {
    grid-template-columns: 1fr;
  }

  .feature-item {
    min-height: 220px;
  }

  .screenshot:nth-child(even) {
    margin-top: 0;
  }

  .screenshot button {
    width: min(100%, 350px);
  }

  .path-link {
    grid-template-columns: 52px 1fr 28px;
    gap: 14px;
  }

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

  .page-stamp {
    display: none;
  }

  .step {
    padding: 42px 0;
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .step::before {
    font-size: 2.6rem;
  }

  .step-aside {
    grid-column: auto;
  }

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

  .manual-nav a {
    padding-right: 10px;
  }

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

  .copyright {
    flex-direction: column;
  }
}

@media (max-width: 420px) {
  .nav-wrap,
  .hero-grid,
  .section-inner,
  .download-band-inner,
  .footer-grid,
  .copyright {
    width: min(100% - 28px, var(--content));
  }

  .brand {
    font-size: 1.1rem;
  }

  .brand img {
    width: 40px;
    height: 40px;
  }

  .hero-actions .button {
    width: 100%;
  }

  .hero-visual {
    min-height: 470px;
  }

  .burst.one {
    right: -8px;
  }

  .burst.two {
    left: -6px;
  }

  .path-link {
    min-height: 130px;
    padding-block: 22px;
  }

  .page-hero {
    padding-top: 58px;
  }

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

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

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