:root {
  --ink: #17252d;
  --ink-soft: #34464f;
  --paper: #f7f6f2;
  --white: #ffffff;
  --coral: #e84f5b;
  --coral-dark: #c93b47;
  --teal: #20b8a5;
  --teal-dark: #128879;
  --yellow: #f4b942;
  --line: #d9dfdf;
  --muted: #66767d;
  --shadow: 0 18px 50px rgba(23, 37, 45, 0.12);
  --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;
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0;
}

body.menu-open {
  overflow: hidden;
}

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

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

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

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

.skip-link {
  position: fixed;
  top: -100px;
  left: 8px;
  z-index: 1000;
  padding: 8px 12px;
  background: var(--white);
  color: var(--ink);
}

.skip-link:focus {
  top: 8px;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(247, 246, 242, 0.96);
  border-bottom: 1px solid rgba(23, 37, 45, 0.12);
  backdrop-filter: blur(12px);
}

.header-inner {
  display: flex;
  min-height: 76px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-size: 21px;
  font-weight: 800;
  line-height: 1;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 8px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.site-nav > a:not(.button) {
  position: relative;
  padding-block: 6px;
  color: var(--ink-soft);
  font-weight: 700;
}

.site-nav > a:not(.button)::after {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 3px;
  background: var(--coral);
  content: "";
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.site-nav > a[aria-current="page"]::after,
.site-nav > a:not(.button):hover::after {
  transform: scaleX(1);
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
  transition: transform 180ms ease, opacity 180ms ease;
}

.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 11px 22px;
  border: 2px solid var(--coral);
  border-radius: 6px;
  background: var(--coral);
  color: var(--white);
  font-weight: 800;
  line-height: 1.2;
  box-shadow: 5px 5px 0 var(--ink);
  transition: transform 150ms ease, box-shadow 150ms ease, background 150ms ease;
}

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

.button.compact {
  min-height: 40px;
  padding: 8px 16px;
  box-shadow: 3px 3px 0 var(--ink);
}

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

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--teal-dark);
  font-weight: 800;
}

.text-link::after {
  content: "\2192";
  transition: transform 150ms ease;
}

.text-link:hover::after {
  transform: translateX(4px);
}

.hero {
  position: relative;
  min-height: 690px;
  overflow: hidden;
  background: var(--ink);
  color: var(--white);
}

.hero::before,
.hero::after {
  position: absolute;
  content: "";
  pointer-events: none;
}

.hero::before {
  top: 0;
  right: 0;
  width: 28%;
  height: 22px;
  background: var(--yellow);
}

.hero::after {
  right: 7%;
  bottom: 0;
  width: 120px;
  height: 38%;
  background: var(--teal);
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  min-height: 690px;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 420px);
  align-items: center;
  gap: 72px;
  padding-block: 64px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 20px;
  color: var(--yellow);
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 28px;
  height: 4px;
  background: currentColor;
  content: "";
}

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

h1 {
  max-width: 760px;
  margin-bottom: 24px;
  font-size: clamp(42px, 7vw, 78px);
}

h2 {
  margin-bottom: 36px;
  font-size: clamp(30px, 4vw, 48px);
}

h3 {
  margin-bottom: 12px;
  font-size: 21px;
}

.hero-copy {
  max-width: 690px;
  margin: 0 0 30px;
  color: #d6e0e3;
  font-size: 19px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px;
  margin-bottom: 30px;
}

.hero-note {
  color: #b9c8cc;
  font-size: 14px;
}

.trust-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 32px;
}

.trust-row span {
  padding: 7px 11px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 999px;
  color: #edf3f4;
  font-size: 13px;
}

.hero-visual {
  position: relative;
  align-self: end;
}

.hero-visual::before {
  position: absolute;
  top: 12%;
  left: -44px;
  width: 76px;
  height: 76px;
  border: 10px solid var(--yellow);
  content: "";
  transform: rotate(9deg);
}

.phone-frame {
  position: relative;
  width: min(100%, 344px);
  margin-inline: auto;
  padding: 10px;
  border: 2px solid #58676d;
  border-radius: 30px;
  background: #0c1418;
  box-shadow: 22px 24px 0 var(--coral);
}

.phone-frame img {
  width: 100%;
  height: auto;
  object-fit: contain;
  border-radius: 22px;
}

.section {
  padding-block: 96px;
}

.section.alt {
  background: var(--white);
}

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

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 36px;
}

.section-heading h2 {
  margin-bottom: 0;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 2px;
  background: var(--ink);
  border: 2px solid var(--ink);
}

.feature-item {
  min-height: 230px;
  padding: 30px;
  background: var(--paper);
}

.feature-item:nth-child(2),
.feature-item:nth-child(5) {
  background: #e8f7f4;
}

.feature-item:nth-child(3),
.feature-item:nth-child(4) {
  background: #fff5dd;
}

.feature-number {
  display: block;
  margin-bottom: 34px;
  color: var(--coral);
  font-size: 15px;
  font-weight: 900;
}

.feature-item p,
.path-step p,
.review blockquote,
.info-panel p {
  margin-bottom: 0;
  color: var(--muted);
}

.showcase-grid {
  display: grid;
  grid-template-columns: 1fr;
  align-items: start;
  gap: 72px;
}

.showcase-item {
  display: grid;
  grid-template-columns: minmax(200px, 400px) minmax(0, 1fr);
  align-items: center;
  gap: 28px;
}

.showcase-grid .showcase-item:nth-child(2) {
  grid-template-columns: minmax(0, 1fr) minmax(200px, 400px);
}

.showcase-grid .showcase-item:nth-child(2) img {
  order: 2;
}

.app-shot {
  width: min(100%, 400px);
  height: auto;
  max-width: 400px;
  border: 2px solid var(--ink);
  box-shadow: 14px 14px 0 var(--yellow);
}

.showcase-item:nth-child(2) .app-shot {
  box-shadow: 14px 14px 0 var(--teal);
}

.shot-copy strong {
  display: block;
  margin-bottom: 10px;
  color: var(--coral);
  font-size: 14px;
}

.path-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
}

.path-step {
  position: relative;
  min-height: 240px;
  padding: 30px 26px;
  border-top: 8px solid var(--teal);
  background: var(--white);
  box-shadow: 0 12px 32px rgba(23, 37, 45, 0.08);
}

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

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

.path-step:nth-child(4) {
  border-color: var(--ink);
}

.path-step b {
  display: block;
  margin-bottom: 30px;
  color: var(--muted);
  font-size: 13px;
}

.deep-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 1px solid rgba(255, 255, 255, 0.18);
}

.deep-link {
  min-height: 280px;
  padding: 42px;
  border-right: 1px solid rgba(255, 255, 255, 0.18);
}

.deep-link:last-child {
  border-right: 0;
}

.deep-link p {
  max-width: 480px;
  color: #b9c8cc;
}

.deep-link .text-link {
  margin-top: 26px;
  color: var(--yellow);
}

.review-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.review {
  padding: 30px;
  border: 2px solid var(--ink);
  background: var(--white);
}

.review:nth-child(2) {
  background: #e8f7f4;
}

.review-stars {
  margin-bottom: 18px;
  color: var(--coral);
  font-size: 18px;
}

.review blockquote {
  margin-inline: 0;
}

.review cite {
  display: block;
  margin-top: 20px;
  color: var(--ink);
  font-size: 14px;
  font-style: normal;
  font-weight: 800;
}

.faq-list {
  border-top: 2px solid var(--ink);
}

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

.faq-list summary {
  position: relative;
  padding: 22px 54px 22px 0;
  cursor: pointer;
  font-size: 18px;
  font-weight: 800;
  list-style: none;
}

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

.faq-list summary::after {
  position: absolute;
  top: 19px;
  right: 4px;
  color: var(--coral);
  content: "+";
  font-size: 28px;
  line-height: 1;
}

.faq-list details[open] summary::after {
  content: "\2212";
}

.faq-answer {
  max-width: 900px;
  padding: 0 54px 22px 0;
  color: var(--muted);
}

.bottom-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 36px;
  padding: 52px;
  background: var(--coral);
  color: var(--white);
}

.bottom-cta h2 {
  margin-bottom: 8px;
}

.bottom-cta p,
.bottom-cta .cta-note {
  display: block;
  margin: 0;
  color: #fff1f2;
}

.site-footer {
  padding-block: 48px 26px;
  background: #0f1a20;
  color: #bfd0d4;
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) auto;
  gap: 44px;
  align-items: start;
}

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

.footer-brand p {
  max-width: 560px;
  margin-bottom: 0;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 28px;
  color: var(--white);
  font-weight: 700;
}

.disclaimer {
  margin: 38px 0 0;
  padding-top: 22px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  font-size: 13px;
}

.copyright {
  margin: 10px 0 0;
  color: #84999f;
  font-size: 13px;
}

.page-hero {
  position: relative;
  overflow: hidden;
  padding-block: 88px 76px;
  background: var(--ink);
  color: var(--white);
}

.page-hero::after {
  position: absolute;
  right: 0;
  bottom: 0;
  width: 30%;
  height: 18px;
  background: var(--teal);
  content: "";
}

.page-hero h1 {
  max-width: 900px;
  font-size: clamp(38px, 6vw, 68px);
}

.page-hero p:not(.eyebrow) {
  max-width: 800px;
  margin-bottom: 0;
  color: #c8d6d9;
  font-size: 18px;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  align-items: start;
  gap: 64px;
}

.article-content section + section {
  margin-top: 64px;
}

.article-content h2 {
  margin-bottom: 24px;
  font-size: 34px;
}

.article-content h3 {
  margin-top: 34px;
}

.article-content p {
  margin: 0 0 18px;
  color: var(--ink-soft);
}

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

.article-content li + li {
  margin-top: 10px;
}

.side-nav {
  position: sticky;
  top: 104px;
  padding: 24px;
  border-left: 5px solid var(--yellow);
  background: var(--white);
}

.side-nav strong {
  display: block;
  margin-bottom: 14px;
}

.side-nav a {
  display: block;
  padding: 7px 0;
  color: var(--muted);
}

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

.step-list {
  display: grid;
  gap: 24px;
  padding: 0;
  counter-reset: guide-step;
  list-style: none;
}

.guide-step {
  position: relative;
  padding: 30px 30px 30px 92px;
  border: 2px solid var(--ink);
  background: var(--white);
  counter-increment: guide-step;
}

.guide-step::before {
  position: absolute;
  top: 28px;
  left: 28px;
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  background: var(--teal);
  color: var(--white);
  content: counter(guide-step, decimal-leading-zero);
  font-size: 13px;
  font-weight: 900;
}

.guide-step:nth-child(even)::before {
  background: var(--coral);
}

.guide-step h3 {
  margin-top: 0;
}

.check-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.check-item {
  padding: 22px;
  border-left: 6px solid var(--teal);
  background: var(--white);
}

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

.check-item p {
  margin: 0;
}

.notice {
  margin-block: 28px;
  padding: 22px 24px;
  border: 2px solid var(--yellow);
  background: #fff8e8;
}

.notice strong {
  color: var(--coral-dark);
}

.info-panel {
  padding: 28px;
  border: 2px solid var(--ink);
  background: var(--white);
}

.info-panel + .info-panel {
  margin-top: 18px;
}

.info-panel h3 {
  margin-top: 0;
}

.topic-tag {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 9px;
  background: var(--yellow);
  color: var(--ink);
  font-size: 12px;
  font-weight: 900;
}

.related-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.related-item {
  padding: 28px;
  border: 2px solid var(--ink);
  background: var(--white);
}

@media (max-width: 1040px) {
  .showcase-item,
  .showcase-grid .showcase-item:nth-child(2) {
    grid-template-columns: minmax(220px, 400px) minmax(0, 1fr);
  }

  .showcase-grid .showcase-item:nth-child(2) img {
    order: 0;
  }

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

@media (max-width: 820px) {
  .container {
    width: min(calc(100% - 28px), var(--content));
  }

  .menu-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    inset: 77px 0 auto 0;
    display: grid;
    gap: 0;
    padding: 18px 20px 28px;
    background: var(--paper);
    border-bottom: 2px solid var(--ink);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-12px);
    transition: opacity 180ms ease, transform 180ms ease;
  }

  .site-nav.open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .site-nav > a:not(.button) {
    padding: 13px 2px;
    border-bottom: 1px solid var(--line);
  }

  .site-nav .button {
    margin-top: 16px;
  }

  .menu-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .menu-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
  }

  .menu-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero,
  .hero-inner {
    min-height: auto;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: 54px;
    padding-block: 72px 92px;
  }

  .hero-visual {
    width: min(88%, 390px);
    justify-self: center;
  }

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

  .deep-links {
    grid-template-columns: 1fr;
  }

  .deep-link {
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  }

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

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

  .bottom-cta,
  .footer-main {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .section {
    padding-block: 68px;
  }

  h1 {
    font-size: 42px;
  }

  h2 {
    font-size: 32px;
  }

  .hero-copy,
  .page-hero p:not(.eyebrow) {
    font-size: 17px;
  }

  .feature-grid,
  .review-grid,
  .path-grid,
  .check-grid,
  .related-band {
    grid-template-columns: 1fr;
  }

  .showcase-item,
  .showcase-grid .showcase-item:nth-child(2) {
    grid-template-columns: 1fr;
  }

  .app-shot {
    justify-self: center;
  }

  .section-heading {
    display: block;
  }

  .section-heading .text-link {
    margin-top: 12px;
  }

  .bottom-cta {
    padding: 34px 26px;
  }

  .guide-step {
    padding: 84px 24px 24px;
  }

  .guide-step::before {
    top: 24px;
    left: 24px;
  }

  .footer-links {
    display: grid;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}