:root {
  --ink: #11150f;
  --ink-2: #181d16;
  --ink-3: #242b20;
  --acid: #b9ff57;
  --acid-soft: #dcffab;
  --lime: #7ccf32;
  --cream: #f3f0e6;
  --cream-2: #e8e3d5;
  --paper: #fffdf7;
  --orange: #ff8b45;
  --text: #1d221b;
  --muted: #6a7065;
  --line: #d8d7cd;
  --line-dark: rgba(255, 255, 255, 0.13);
  --success: #50c878;
  --shell: 1180px;
  --shadow: 0 30px 90px rgba(14, 18, 12, 0.18);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.72;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

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

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

button {
  font: inherit;
}

.skip-link {
  position: fixed;
  top: -80px;
  left: 20px;
  z-index: 999;
  padding: 10px 15px;
  border: 1px solid var(--acid);
  color: var(--acid);
  background: var(--ink);
  font-weight: 900;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 18px;
}

.header-shell,
.section-shell,
.footer-shell {
  width: min(calc(100% - 40px), var(--shell));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(17, 21, 15, 0.94);
  backdrop-filter: blur(18px);
}

.header-shell {
  min-height: 76px;
  display: grid;
  grid-template-columns: 220px 1fr 165px;
  align-items: center;
  gap: 28px;
}

.brand {
  width: max-content;
}

.brand img,
.footer-brand img {
  width: auto;
  height: 37px;
  object-fit: contain;
  filter: brightness(0) invert(1);
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 29px;
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
  font-weight: 760;
}

.site-nav a {
  position: relative;
  padding: 26px 0 23px;
}

.site-nav a::before {
  content: "";
  position: absolute;
  left: 0;
  bottom: 18px;
  width: 100%;
  height: 2px;
  background: var(--acid);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.2s ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: #fff;
}

.site-nav a:hover::before,
.site-nav a:focus-visible::before {
  transform: scaleX(1);
  transform-origin: left;
}

.header-download {
  justify-self: end;
  min-width: 155px;
  padding: 11px 16px;
  border: 1px solid var(--acid);
  color: var(--ink);
  background: var(--acid);
  text-align: center;
  font-size: 14px;
  font-weight: 920;
  box-shadow: 4px 4px 0 rgba(255, 255, 255, 0.18);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.header-download:hover,
.header-download:focus-visible {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0 rgba(255, 255, 255, 0.18);
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  color: #fff;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: #fff;
}

.hero {
  position: relative;
  overflow: hidden;
  padding: 90px 0 96px;
  color: #fff;
  background:
    radial-gradient(circle at 85% 16%, rgba(185, 255, 87, 0.13), transparent 24%),
    radial-gradient(circle at 8% 90%, rgba(255, 139, 69, 0.08), transparent 26%),
    var(--ink);
}

.hero::before {
  content: "ANDROID";
  position: absolute;
  right: -55px;
  top: 45px;
  color: rgba(255, 255, 255, 0.025);
  font-size: clamp(110px, 18vw, 280px);
  font-weight: 1000;
  line-height: 0.8;
  letter-spacing: -0.09em;
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  right: 7%;
  bottom: -260px;
  width: 520px;
  height: 520px;
  border: 1px solid rgba(185, 255, 87, 0.14);
  border-radius: 50%;
  box-shadow: 0 0 0 65px rgba(185, 255, 87, 0.025), 0 0 0 130px rgba(185, 255, 87, 0.018);
  pointer-events: none;
}

.hero-grid {
  position: absolute;
  inset: 0;
  opacity: 0.18;
  background-image:
    linear-gradient(rgba(255,255,255,0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.055) 1px, transparent 1px);
  background-size: 50px 50px;
  mask-image: linear-gradient(90deg, #000 0%, transparent 72%);
  pointer-events: none;
}

.hero-shell {
  position: relative;
  z-index: 2;
  width: min(calc(100% - 40px), var(--shell));
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(400px, 0.92fr);
  align-items: center;
  gap: 74px;
}

.platform-tag {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 22px;
  color: var(--acid);
  font-size: 12px;
  font-weight: 950;
  letter-spacing: 0.18em;
}

.platform-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--acid);
  box-shadow: 0 0 0 6px rgba(185, 255, 87, 0.1);
}

.hero h1 {
  max-width: 720px;
  margin: 0;
  font-size: clamp(48px, 7.2vw, 92px);
  line-height: 0.98;
  letter-spacing: -0.065em;
}

.hero-lead {
  max-width: 730px;
  margin: 27px 0 0;
  color: rgba(255, 255, 255, 0.72);
  font-size: clamp(16px, 1.8vw, 19px);
  line-height: 1.88;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
  margin-top: 31px;
}

.primary-action {
  min-width: 270px;
  min-height: 68px;
  display: inline-flex;
  align-items: center;
  gap: 16px;
  padding: 10px 22px;
  color: var(--ink);
  background: var(--acid);
  font-weight: 900;
  box-shadow: 7px 7px 0 rgba(255, 255, 255, 0.16);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.primary-action:hover,
.primary-action:focus-visible {
  transform: translate(3px, 3px);
  box-shadow: 3px 3px 0 rgba(255, 255, 255, 0.16);
}

.action-icon {
  width: 39px;
  height: 39px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(17, 21, 15, 0.28);
  border-radius: 50%;
  font-size: 21px;
}

.primary-action span:last-child {
  display: grid;
}

.primary-action small {
  font-size: 10px;
  letter-spacing: 0.16em;
}

.primary-action strong {
  font-size: 16px;
}

.secondary-action {
  padding: 10px 0 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.35);
  color: #fff;
  font-size: 14px;
  font-weight: 820;
}

.secondary-action:hover,
.secondary-action:focus-visible {
  border-color: var(--acid);
  color: var(--acid);
}

.direct-answer {
  max-width: 730px;
  margin: 30px 0 0;
  padding: 16px 19px;
  border-left: 3px solid var(--orange);
  color: rgba(255, 255, 255, 0.72);
  background: rgba(255, 255, 255, 0.045);
  font-size: 14px;
}

.direct-answer strong {
  color: #fff;
}

.installer {
  position: relative;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(26, 31, 23, 0.88);
  box-shadow: 18px 18px 0 rgba(185, 255, 87, 0.055), var(--shadow);
}

.installer::before {
  content: "";
  position: absolute;
  inset: 12px -12px -12px 12px;
  z-index: -1;
  border: 1px solid rgba(185, 255, 87, 0.18);
}

.installer-head {
  min-height: 47px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 17px;
  border-bottom: 1px solid var(--line-dark);
  background: rgba(255, 255, 255, 0.035);
}

.installer-head > div {
  display: flex;
  gap: 7px;
}

.window-dot {
  width: 8px;
  height: 8px;
  display: block;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
}

.window-dot:nth-child(1) { background: var(--orange); }
.window-dot:nth-child(2) { background: #ffd657; }
.window-dot:nth-child(3) { background: var(--acid); }

.installer-head small {
  color: rgba(255, 255, 255, 0.46);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.16em;
}

.installer-body {
  padding: 27px;
}

.app-row {
  display: flex;
  align-items: center;
  gap: 17px;
  padding-bottom: 23px;
  border-bottom: 1px solid var(--line-dark);
}

.app-row img {
  width: 70px;
  height: 70px;
  border-radius: 15px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.22);
}

.app-row div {
  display: grid;
}

.app-row span {
  color: var(--acid);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.app-row strong {
  margin-top: 2px;
  font-size: 20px;
  line-height: 1.3;
}

.app-row small {
  margin-top: 5px;
  color: rgba(255, 255, 255, 0.48);
  font-size: 12px;
}

.check-list {
  display: grid;
  margin-top: 17px;
}

.check-item {
  min-height: 67px;
  display: grid;
  grid-template-columns: 38px 1fr auto;
  align-items: center;
  gap: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.check-item > span {
  color: rgba(255, 255, 255, 0.28);
  font-size: 12px;
  font-weight: 900;
}

.check-item > div {
  display: grid;
}

.check-item b {
  font-size: 13px;
}

.check-item small {
  color: rgba(255, 255, 255, 0.5);
  font-size: 11px;
}

.check-item i {
  min-width: 49px;
  padding: 4px 7px;
  border: 1px solid rgba(185, 255, 87, 0.28);
  color: var(--acid);
  font-size: 8px;
  font-style: normal;
  font-weight: 950;
  letter-spacing: 0.1em;
  text-align: center;
}

.installer-progress {
  margin-top: 20px;
}

.installer-progress > div:first-child {
  display: flex;
  justify-content: space-between;
  margin-bottom: 8px;
  color: rgba(255, 255, 255, 0.58);
  font-size: 11px;
}

.installer-progress b {
  color: #fff;
}

.progress-track {
  height: 8px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.08);
}

.progress-track span {
  width: 78%;
  height: 100%;
  display: block;
  background: linear-gradient(90deg, var(--acid), #72d837);
}

.installer-button {
  min-height: 53px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 22px;
  padding: 0 17px;
  color: var(--ink);
  background: var(--acid);
  font-size: 13px;
  font-weight: 930;
}

.installer-button span {
  font-size: 18px;
}

.installer-body > p {
  margin: 10px 0 0;
  color: rgba(255, 255, 255, 0.38);
  font-size: 10px;
  text-align: center;
}

.answer-strip {
  border-bottom: 1px solid var(--line);
  background: var(--cream);
}

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

.answer-grid > div {
  min-height: 105px;
  display: grid;
  align-content: center;
  gap: 4px;
  padding: 18px 24px;
  border-right: 1px solid var(--line);
}

.answer-grid > div:first-child {
  border-left: 1px solid var(--line);
}

.answer-grid span {
  color: var(--muted);
  font-size: 11px;
  font-weight: 850;
  letter-spacing: 0.09em;
}

.answer-grid strong {
  font-size: 15px;
}

.intro-section {
  padding: 112px 0;
  background: var(--paper);
}

.intro-layout {
  display: grid;
  grid-template-columns: 100px minmax(0, 1fr) 350px;
  align-items: start;
  gap: 56px;
}

.intro-index {
  display: grid;
  justify-items: center;
  gap: 14px;
  padding-top: 7px;
}

.intro-index span {
  font-size: 46px;
  font-weight: 1000;
  line-height: 1;
  letter-spacing: -0.05em;
}

.intro-index i {
  width: 1px;
  height: 140px;
  background: var(--line);
}

.intro-index small {
  writing-mode: vertical-rl;
  color: var(--muted);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.18em;
}

.section-kicker {
  margin: 0 0 10px;
  color: #5e942c;
  font-size: 11px;
  font-weight: 950;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.intro-copy h2,
.section-heading h2,
.install-heading h2,
.safety-title-wrap h2,
.faq-heading h2,
.final-copy h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(31px, 4.5vw, 52px);
  line-height: 1.16;
  letter-spacing: -0.045em;
}

.intro-copy > p:not(.section-kicker) {
  margin: 22px 0 0;
  color: #51574e;
  font-size: 16px;
}

.intro-callout {
  margin-top: 28px;
  padding: 18px 20px;
  border-left: 4px solid var(--acid);
  background: var(--cream);
}

.intro-callout b,
.intro-callout span {
  display: block;
}

.intro-callout b {
  color: var(--ink);
  font-size: 14px;
}

.intro-callout span {
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
}

.entry-panel {
  position: sticky;
  top: 105px;
  padding: 30px;
  border-top: 5px solid var(--acid);
  color: #fff;
  background: var(--ink);
  box-shadow: 12px 12px 0 var(--cream-2);
}

.entry-label {
  color: var(--acid);
  font-size: 9px;
  font-weight: 950;
  letter-spacing: 0.17em;
}

.entry-panel h3 {
  margin: 15px 0 0;
  font-size: 25px;
  line-height: 1.25;
}

.entry-panel p {
  margin: 16px 0 0;
  color: rgba(255, 255, 255, 0.63);
  font-size: 13px;
}

.panel-link {
  min-height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 23px;
  padding: 0 15px;
  color: var(--ink);
  background: var(--acid);
  font-size: 13px;
  font-weight: 900;
}

.requirements-section {
  padding: 106px 0;
  border-top: 1px solid var(--line);
  background: var(--cream);
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.75fr);
  align-items: end;
  gap: 70px;
  margin-bottom: 42px;
}

.section-heading > p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
}

.requirements-table {
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.requirement-row {
  display: grid;
  grid-template-columns: 1.1fr 0.8fr 0.9fr 1.55fr;
  min-height: 88px;
  border-bottom: 1px solid var(--line);
}

.requirement-row:last-child {
  border-bottom: 0;
}

.requirement-row > span {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 17px 20px;
  border-right: 1px solid var(--line);
  font-size: 14px;
}

.requirement-row > span:last-child {
  border-right: 0;
}

.requirement-row b {
  color: var(--ink);
  font-size: 15px;
}

.requirement-row small {
  color: var(--muted);
  font-size: 11px;
}

.requirement-row strong {
  width: max-content;
  padding: 4px 8px;
  color: var(--ink);
  background: var(--acid-soft);
  font-size: 13px;
}

.requirement-head {
  min-height: 50px;
  color: rgba(255, 255, 255, 0.65);
  background: var(--ink);
}

.requirement-head > span {
  border-color: rgba(255, 255, 255, 0.12);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.11em;
}

.source-note {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 12px;
}

.install-section {
  padding: 110px 0;
  background: var(--paper);
}

.install-shell {
  display: grid;
  grid-template-columns: 0.78fr 1.22fr;
  gap: 90px;
}

.install-heading {
  position: sticky;
  top: 115px;
  align-self: start;
}

.install-heading p:last-child {
  margin: 22px 0 0;
  color: var(--muted);
}

.install-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 2px solid var(--ink);
}

.install-steps li {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 25px;
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.step-number {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  border: 1px solid var(--ink);
  color: var(--ink);
  background: var(--acid);
  font-weight: 1000;
}

.step-content small {
  color: #6f9d3f;
  font-size: 9px;
  font-weight: 950;
  letter-spacing: 0.15em;
}

.step-content h3 {
  margin: 5px 0 0;
  color: var(--ink);
  font-size: 21px;
  line-height: 1.3;
}

.step-content p {
  margin: 9px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.safety-section {
  padding: 83px 0;
  color: #fff;
  background: var(--ink-3);
}

.safety-layout {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 85px;
}

.safety-title-wrap {
  display: grid;
  grid-template-columns: 70px 1fr;
  align-items: start;
  gap: 20px;
}

.safety-mark {
  width: 66px;
  height: 66px;
  display: grid;
  place-items: center;
  border: 1px solid var(--acid);
  color: var(--acid);
  font-size: 34px;
  font-weight: 900;
}

.safety-title-wrap h2 {
  color: #fff;
  font-size: clamp(30px, 4vw, 46px);
}

.safety-copy > p {
  margin: 0;
  color: rgba(255, 255, 255, 0.66);
}

.safety-copy ul {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.safety-copy li {
  padding: 14px 0 14px 25px;
  border-top: 1px solid rgba(255, 255, 255, 0.11);
  color: rgba(255, 255, 255, 0.62);
  font-size: 14px;
}

.safety-copy li::before {
  content: "+";
  float: left;
  margin-left: -25px;
  color: var(--acid);
  font-weight: 950;
}

.safety-copy b {
  color: #fff;
}

.troubleshooting-section {
  padding: 110px 0;
  color: #fff;
  background: var(--ink);
}

.section-heading-light h2 {
  color: #fff;
}

.section-heading-light > p {
  color: rgba(255, 255, 255, 0.58);
}

.issue-list {
  border-top: 1px solid rgba(255, 255, 255, 0.18);
}

.issue-item {
  display: grid;
  grid-template-columns: 70px 1fr 170px;
  align-items: center;
  gap: 25px;
  min-height: 132px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.13);
  transition: background 0.2s ease, padding 0.2s ease;
}

.issue-item:hover {
  padding-inline: 15px;
  background: rgba(255, 255, 255, 0.03);
}

.issue-item > span {
  color: var(--acid);
  font-size: 14px;
  font-weight: 1000;
}

.issue-item h3 {
  margin: 0;
  font-size: 20px;
}

.issue-item p {
  margin: 7px 0 0;
  color: rgba(255, 255, 255, 0.56);
  font-size: 13px;
}

.issue-item > b {
  justify-self: end;
  padding: 7px 10px;
  border: 1px solid rgba(185, 255, 87, 0.32);
  color: var(--acid);
  font-size: 10px;
  letter-spacing: 0.08em;
}

.faq-section {
  padding: 110px 0;
  background: var(--cream);
}

.faq-layout {
  display: grid;
  grid-template-columns: 0.78fr 1.22fr;
  gap: 90px;
}

.faq-heading {
  align-self: start;
}

.faq-heading p:not(.section-kicker) {
  margin: 22px 0 0;
  color: var(--muted);
}

.faq-download {
  min-height: 54px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 26px;
  padding: 0 17px;
  color: #fff;
  background: var(--ink);
  font-size: 13px;
  font-weight: 900;
}

.faq-download span {
  color: var(--acid);
  font-size: 18px;
}

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

.faq-list details {
  border-bottom: 1px solid #c8c6bb;
}

.faq-list summary {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  color: var(--ink);
  font-size: 16px;
  font-weight: 850;
  cursor: pointer;
  list-style: none;
}

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

.faq-list summary span {
  position: relative;
  width: 26px;
  height: 26px;
  flex: 0 0 auto;
  border: 1px solid var(--ink);
}

.faq-list summary span::before,
.faq-list summary span::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 1px;
  background: var(--ink);
  transform: translate(-50%, -50%);
  transition: transform 0.2s ease;
}

.faq-list summary span::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.faq-list details[open] summary span {
  background: var(--acid);
}

.faq-list details[open] summary span::after {
  transform: translate(-50%, -50%) rotate(0deg);
}

.faq-list details p {
  margin: -3px 50px 25px 0;
  color: var(--muted);
  font-size: 14px;
}

.final-download {
  padding: 75px 0;
  border-top: 1px solid var(--line);
  background: var(--paper);
}

.final-shell {
  display: grid;
  grid-template-columns: 90px 1fr 190px;
  align-items: center;
  gap: 30px;
}

.final-icon {
  width: 84px;
  height: 84px;
  padding: 8px;
  border: 1px solid var(--line);
  background: var(--cream);
}

.final-icon img {
  width: 100%;
  height: 100%;
  border-radius: 14px;
}

.final-copy > span {
  color: #649638;
  font-size: 10px;
  font-weight: 950;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.final-copy h2 {
  margin-top: 5px;
  font-size: clamp(27px, 3.5vw, 40px);
}

.final-copy p {
  margin: 9px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.final-button {
  min-height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 18px;
  color: var(--ink);
  background: var(--acid);
  font-size: 14px;
  font-weight: 920;
  box-shadow: 5px 5px 0 var(--ink);
}

.site-footer {
  color: rgba(255, 255, 255, 0.6);
  background: #0b0d0a;
}

.footer-shell {
  display: grid;
  grid-template-columns: 1.5fr 0.6fr 0.9fr;
  gap: 80px;
  padding: 70px 0 55px;
}

.footer-brand img {
  height: 36px;
}

.footer-brand p,
.footer-notice p {
  max-width: 480px;
  margin: 18px 0 0;
  font-size: 12px;
}

.footer-links,
.footer-notice {
  display: grid;
  align-content: start;
  gap: 9px;
}

.footer-links strong,
.footer-notice strong {
  margin-bottom: 7px;
  color: #fff;
  font-size: 12px;
}

.footer-links a {
  width: max-content;
  font-size: 12px;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom .section-shell {
  min-height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  font-size: 11px;
}

.footer-bottom a {
  color: var(--acid);
}

@media (max-width: 1040px) {
  .header-shell {
    grid-template-columns: 190px 1fr 155px;
    gap: 18px;
  }

  .site-nav {
    gap: 18px;
  }

  .hero-shell {
    grid-template-columns: 1fr 390px;
    gap: 42px;
  }

  .intro-layout {
    grid-template-columns: 70px 1fr 310px;
    gap: 35px;
  }

  .install-shell,
  .faq-layout {
    gap: 55px;
  }
}

@media (max-width: 880px) {
  html {
    scroll-padding-top: 74px;
  }

  .header-shell {
    min-height: 70px;
    grid-template-columns: 1fr auto;
  }

  .brand img {
    height: 34px;
  }

  .header-download {
    display: none;
  }

  .menu-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    left: 20px;
    right: 20px;
    top: 70px;
    display: none;
    padding: 10px;
    border: 1px solid rgba(255,255,255,0.12);
    background: var(--ink-2);
    box-shadow: 0 20px 50px rgba(0,0,0,0.25);
  }

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

  .site-nav a {
    padding: 12px 13px;
  }

  .site-nav a::before {
    display: none;
  }

  .hero {
    padding: 70px 0 78px;
  }

  .hero-shell {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .hero-copy {
    text-align: center;
  }

  .platform-tag,
  .hero-actions {
    justify-content: center;
  }

  .hero-lead,
  .direct-answer {
    margin-inline: auto;
  }

  .installer {
    width: min(520px, 100%);
    margin-inline: auto;
  }

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

  .answer-grid > div:nth-child(3) {
    border-left: 1px solid var(--line);
    border-top: 1px solid var(--line);
  }

  .answer-grid > div:nth-child(4) {
    border-top: 1px solid var(--line);
  }

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

  .intro-index {
    display: none;
  }

  .entry-panel {
    position: static;
  }

  .section-heading,
  .install-shell,
  .safety-layout,
  .faq-layout {
    grid-template-columns: 1fr;
    gap: 35px;
  }

  .install-heading {
    position: static;
  }

  .requirement-row {
    grid-template-columns: 1fr 0.72fr 0.8fr;
  }

  .requirement-row > span:nth-child(4) {
    grid-column: 1 / -1;
    border-top: 1px solid var(--line);
    border-right: 0;
    background: rgba(0,0,0,0.018);
  }

  .requirement-head > span:nth-child(4) {
    display: none;
  }

  .issue-item {
    grid-template-columns: 55px 1fr;
  }

  .issue-item > b {
    grid-column: 2;
    justify-self: start;
    margin-bottom: 20px;
  }

  .final-shell {
    grid-template-columns: 75px 1fr;
  }

  .final-button {
    grid-column: 1 / -1;
    width: min(320px, 100%);
  }

  .footer-shell {
    grid-template-columns: 1.3fr 0.7fr;
    gap: 45px;
  }

  .footer-notice {
    grid-column: 1 / -1;
  }
}

@media (max-width: 600px) {
  .header-shell,
  .section-shell,
  .footer-shell,
  .hero-shell {
    width: min(calc(100% - 28px), var(--shell));
  }

  .site-nav {
    left: 14px;
    right: 14px;
  }

  .hero {
    padding: 55px 0 62px;
  }

  .hero::before {
    right: -25px;
    top: 25px;
    font-size: 100px;
  }

  .hero h1 {
    font-size: clamp(43px, 14vw, 64px);
  }

  .hero-lead {
    font-size: 15px;
  }

  .hero-actions {
    display: grid;
    width: 100%;
  }

  .primary-action {
    min-width: 0;
    width: 100%;
  }

  .secondary-action {
    justify-self: center;
  }

  .direct-answer {
    text-align: left;
  }

  .installer-body {
    padding: 20px;
  }

  .app-row img {
    width: 58px;
    height: 58px;
  }

  .app-row strong {
    font-size: 16px;
  }

  .check-item {
    grid-template-columns: 28px 1fr;
  }

  .check-item i {
    grid-column: 2;
    justify-self: start;
    margin-bottom: 9px;
  }

  .answer-grid {
    grid-template-columns: 1fr;
  }

  .answer-grid > div,
  .answer-grid > div:nth-child(3),
  .answer-grid > div:nth-child(4) {
    min-height: 86px;
    border: 0;
    border-bottom: 1px solid var(--line);
  }

  .answer-grid > div:first-child {
    border-left: 0;
  }

  .intro-section,
  .requirements-section,
  .install-section,
  .troubleshooting-section,
  .faq-section {
    padding: 78px 0;
  }

  .intro-copy h2,
  .section-heading h2,
  .install-heading h2,
  .safety-title-wrap h2,
  .faq-heading h2 {
    font-size: 34px;
  }

  .entry-panel {
    padding: 24px;
  }

  .requirements-table {
    border-top-width: 1px;
  }

  .requirement-row,
  .requirement-head {
    grid-template-columns: 1fr 1fr;
  }

  .requirement-head > span:nth-child(3),
  .requirement-head > span:nth-child(4) {
    display: none;
  }

  .requirement-row > span:nth-child(3),
  .requirement-row > span:nth-child(4) {
    grid-column: 1 / -1;
    border-top: 1px solid var(--line);
    border-right: 0;
  }

  .requirement-row > span:nth-child(3)::before {
    content: "建议配置";
    margin-bottom: 4px;
    color: var(--muted);
    font-size: 10px;
    font-weight: 850;
  }

  .install-steps li {
    grid-template-columns: 55px 1fr;
    gap: 15px;
    padding: 24px 0;
  }

  .step-number {
    width: 46px;
    height: 46px;
    font-size: 13px;
  }

  .safety-section {
    padding: 70px 0;
  }

  .safety-title-wrap {
    grid-template-columns: 52px 1fr;
    gap: 15px;
  }

  .safety-mark {
    width: 50px;
    height: 50px;
    font-size: 25px;
  }

  .issue-item {
    grid-template-columns: 36px 1fr;
    gap: 12px;
    padding: 24px 0;
  }

  .issue-item:hover {
    padding-inline: 0;
  }

  .faq-list summary {
    min-height: 72px;
    font-size: 15px;
  }

  .faq-list details p {
    margin-right: 0;
  }

  .final-download {
    padding: 62px 0;
  }

  .final-shell {
    grid-template-columns: 62px 1fr;
    gap: 18px;
  }

  .final-icon {
    width: 62px;
    height: 62px;
  }

  .final-copy h2 {
    font-size: 26px;
  }

  .footer-shell {
    grid-template-columns: 1fr;
    gap: 35px;
    padding: 55px 0 42px;
  }

  .footer-notice {
    grid-column: auto;
  }

  .footer-bottom .section-shell {
    min-height: 68px;
    align-items: flex-start;
    justify-content: center;
    flex-direction: column;
    gap: 4px;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}