:root {
  color-scheme: light;
  --bg: #f5f5f7;
  --surface: #ffffff;
  --surface-soft: #eeeeF2;
  --text: #1d1d1f;
  --secondary: #6e6e73;
  --tertiary: #8e8e93;
  --accent: #ff5a52;
  --accent-strong: #e94640;
  --accent-text: #1d1d1f;
  --line: rgba(29, 29, 31, 0.1);
  --control-hover: rgba(29, 29, 31, 0.06);
  --nav-bg: rgba(250, 250, 252, 0.72);
  --focus: #0071e3;
  --shadow-soft: 0 12px 40px rgba(0, 0, 0, 0.07);
  --shadow-preview: 0 24px 70px rgba(0, 0, 0, 0.11);
  --shell: min(1120px, calc(100% - 48px));
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0b0b0d;
  --surface: #1c1c1e;
  --surface-soft: #242426;
  --text: #f5f5f7;
  --secondary: #a1a1a6;
  --tertiary: #8e8e93;
  --accent: #ff6961;
  --accent-strong: #ff7c75;
  --accent-text: #1d1d1f;
  --line: rgba(255, 255, 255, 0.11);
  --control-hover: rgba(255, 255, 255, 0.09);
  --nav-bg: rgba(28, 28, 30, 0.72);
  --focus: #2997ff;
  --shadow-soft: 0 12px 40px rgba(0, 0, 0, 0.2);
  --shadow-preview: 0 28px 80px rgba(0, 0, 0, 0.34);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
  background: var(--bg);
}

body {
  min-width: 320px;
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font-family:
    -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Helvetica Neue", sans-serif;
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition:
    color 220ms ease,
    background-color 220ms ease;
}

button,
a {
  color: inherit;
  font: inherit;
}

button {
  padding: 0;
}

a {
  text-decoration: none;
}

img,
svg {
  display: block;
}

img {
  max-width: 100%;
}

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

button:focus-visible,
a:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--focus) 42%, transparent);
  outline-offset: 3px;
}

.section-shell {
  width: var(--shell);
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 100;
  padding: 10px 14px;
  color: white;
  background: #1d1d1f;
  border-radius: 10px;
  transform: translateY(-160%);
  transition: transform 180ms ease;
}

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

.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 50;
  padding: 14px 0;
  pointer-events: none;
}

.nav-shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: var(--shell);
  min-height: 60px;
  padding: 8px 10px 8px 14px;
  margin-inline: auto;
  background: color-mix(in srgb, var(--nav-bg) 58%, transparent);
  border: 1px solid transparent;
  border-radius: 18px;
  pointer-events: auto;
  transition:
    background-color 220ms ease,
    border-color 220ms ease,
    box-shadow 220ms ease,
    backdrop-filter 220ms ease;
}

.site-header.is-scrolled .nav-shell {
  background: var(--nav-bg);
  border-color: var(--line);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
  backdrop-filter: blur(22px) saturate(160%);
  -webkit-backdrop-filter: blur(22px) saturate(160%);
}

.brand {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  min-height: 44px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.brand-mark {
  position: relative;
  display: block;
  width: 34px;
  height: 34px;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.brand-sun {
  position: absolute;
  top: 7px;
  right: 7px;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
}

.brand-mountain {
  position: absolute;
  bottom: 6px;
  width: 0;
  height: 0;
  border-right: 9px solid transparent;
  border-left: 9px solid transparent;
  border-bottom: 14px solid #78837d;
}

.brand-mountain-left {
  left: 3px;
}

.brand-mountain-right {
  right: 1px;
  border-right-width: 8px;
  border-bottom-width: 11px;
  border-left-width: 8px;
  border-bottom-color: #34413b;
}

.header-actions {
  display: flex;
  gap: 4px;
  align-items: center;
}

.header-control {
  display: inline-flex;
  gap: 7px;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  height: 44px;
  padding: 0 12px;
  background: transparent;
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  transition:
    color 160ms ease,
    background-color 160ms ease,
    transform 100ms ease-out;
}

.header-control:active {
  transform: scale(0.96);
}

.language-toggle {
  color: var(--secondary);
  font-size: 12px;
  font-weight: 650;
}

.language-toggle i {
  color: var(--tertiary);
  font-style: normal;
  opacity: 0.55;
}

html[lang="zh-CN"] .language-zh,
html[lang="en"] .language-en {
  color: var(--text);
}

.support-link {
  color: var(--secondary);
  font-size: 13px;
  font-weight: 600;
}

.support-link svg,
.theme-toggle svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.6;
}

.support-link svg {
  color: var(--accent);
  fill: color-mix(in srgb, var(--accent) 10%, transparent);
}

.theme-toggle {
  position: relative;
}

.theme-icon {
  position: absolute;
}

.theme-icon-sun {
  opacity: 0;
  transform: scale(0.75);
}

html[data-theme="dark"] .theme-icon-moon {
  opacity: 0;
  transform: scale(0.75);
}

html[data-theme="dark"] .theme-icon-sun {
  opacity: 1;
  transform: scale(1);
}

.theme-icon {
  transition:
    opacity 180ms ease,
    transform 180ms ease;
}

.hero {
  display: grid;
  grid-template-columns: minmax(350px, 0.84fr) minmax(540px, 1.16fr);
  gap: clamp(48px, 6vw, 84px);
  align-items: center;
  min-height: 760px;
  padding: 132px 0 84px;
}

.hero-copy {
  max-width: 520px;
}

.product-label {
  margin: 0 0 20px;
  color: var(--accent-strong);
  font-size: 13px;
  font-weight: 650;
  letter-spacing: 0.01em;
}

.hero h1 {
  margin: 0;
  font-family:
    -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", sans-serif;
  font-size: clamp(50px, 5.6vw, 78px);
  font-weight: 720;
  line-height: 1.05;
  letter-spacing: -0.055em;
  text-wrap: balance;
}

.hero-lead {
  max-width: 470px;
  margin: 28px 0 0;
  color: var(--secondary);
  font-size: clamp(17px, 1.5vw, 20px);
  line-height: 1.65;
  letter-spacing: -0.012em;
}

.trust-line {
  margin: 22px 0 0;
  color: var(--tertiary);
  font-size: 13px;
}

.hero-product {
  min-width: 0;
}

.hero-preview {
  margin: 0;
  padding: 8px;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow-preview);
}

.hero-preview img {
  width: 100%;
  height: auto;
  border-radius: 17px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  align-items: center;
  justify-content: center;
  margin-top: 24px;
}

.button {
  display: inline-flex;
  gap: 12px;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 22px;
  font-size: 14px;
  font-weight: 650;
  border: 1px solid transparent;
  border-radius: 14px;
  transition:
    background-color 160ms ease,
    border-color 160ms ease,
    box-shadow 160ms ease,
    transform 100ms ease-out;
}

.button:active,
.destination-badges a:active {
  transform: scale(0.97);
}

.button svg {
  width: 18px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.button-primary {
  color: var(--accent-text);
  background: var(--accent);
  box-shadow: 0 8px 24px color-mix(in srgb, var(--accent) 24%, transparent);
}

.button-secondary {
  background: var(--surface);
  border-color: var(--line);
}

.features {
  padding: 112px 0;
  border-top: 1px solid var(--line);
}

.section-heading {
  max-width: 680px;
  margin-bottom: 48px;
}

.section-heading h2,
.install-panel h2 {
  margin: 0;
  font-family:
    -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", sans-serif;
  font-size: clamp(38px, 5vw, 60px);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.045em;
}

.section-heading > p,
.install-panel > div > p {
  max-width: 620px;
  margin: 18px 0 0;
  color: var(--secondary);
  font-size: 18px;
  line-height: 1.65;
  letter-spacing: -0.01em;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.feature-card {
  min-height: 250px;
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow-soft);
}

.feature-icon {
  display: grid;
  width: 42px;
  height: 42px;
  color: var(--accent-strong);
  background: color-mix(in srgb, var(--accent) 12%, var(--surface));
  border-radius: 12px;
  place-items: center;
}

.feature-icon svg {
  width: 23px;
  height: 23px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.6;
}

.feature-card h3 {
  margin: 28px 0 10px;
  font-size: 21px;
  font-weight: 680;
  line-height: 1.2;
  letter-spacing: -0.025em;
}

.feature-card p {
  margin: 0;
  color: var(--secondary);
  line-height: 1.65;
}

.inline-link {
  display: inline-block;
  margin-top: 18px;
  color: var(--focus);
  font-size: 14px;
  font-weight: 600;
}

.inline-link::after {
  content: " ↗";
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 16px;
}

.preview-card {
  margin: 0;
  padding: 12px 12px 18px;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 24px;
}

.preview-card img {
  width: 100%;
  height: clamp(420px, 44vw, 610px);
  object-fit: contain;
  background: var(--surface-soft);
  border-radius: 16px;
}

.preview-card figcaption {
  padding: 16px 8px 0;
  color: var(--secondary);
  font-size: 14px;
  text-align: center;
}

.install {
  padding: 24px 0 120px;
}

.install-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 56px;
  align-items: center;
  padding: clamp(40px, 6vw, 72px);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 32px;
  box-shadow: var(--shadow-soft);
}

.install-panel h2 {
  font-size: clamp(36px, 4.5vw, 54px);
}

.install-panel > div > p {
  max-width: 560px;
  font-size: 17px;
}

.destination-badges {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 224px;
}

.destination-badges a {
  display: block;
  overflow: hidden;
  border-radius: 10px;
  transition:
    opacity 160ms ease,
    transform 100ms ease-out;
}

.destination-badges img {
  width: 100%;
  height: auto;
}

.site-footer {
  border-top: 1px solid var(--line);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 104px;
  color: var(--secondary);
  font-size: 13px;
}

.footer-inner p {
  margin: 0;
}

.footer-links {
  display: flex;
  gap: 24px;
}

.footer-links a {
  transition: color 160ms ease;
}

[data-reveal] {
  opacity: 1;
}

[data-reveal].reveal-pending {
  opacity: 0;
  transform: translateY(12px);
}

[data-reveal].reveal-pending.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 480ms cubic-bezier(0.22, 1, 0.36, 1),
    transform 480ms cubic-bezier(0.22, 1, 0.36, 1);
}

[data-delay="1"].reveal-pending.is-visible {
  transition-delay: 70ms;
}

[data-delay="2"].reveal-pending.is-visible {
  transition-delay: 140ms;
}

@media (hover: hover) {
  .header-control:hover {
    color: var(--text);
    background: var(--control-hover);
  }

  .button-primary:hover {
    background: var(--accent-strong);
  }

  .button-secondary:hover {
    background: var(--control-hover);
    border-color: color-mix(in srgb, var(--text) 18%, transparent);
  }

  .destination-badges a:hover {
    opacity: 0.82;
  }

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

@media (max-width: 980px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 56px;
    min-height: auto;
    padding: 150px 0 96px;
  }

  .hero-copy {
    max-width: 720px;
    margin-inline: auto;
    text-align: center;
  }

  .hero-lead {
    max-width: 620px;
    margin-inline: auto;
    margin-top: 24px;
  }

  .hero-product {
    width: min(760px, 100%);
    margin-inline: auto;
  }

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

  .feature-card {
    min-height: auto;
  }

  .install-panel {
    grid-template-columns: 1fr;
  }

  .destination-badges {
    flex-direction: row;
    width: auto;
  }

  .destination-badges a {
    width: 210px;
  }
}

@media (max-width: 680px) {
  :root {
    --shell: min(100% - 32px, 1120px);
  }

  html {
    scroll-padding-top: 82px;
  }

  .site-header {
    padding-top: 8px;
  }

  .nav-shell {
    min-height: 56px;
    padding: 6px 6px 6px 10px;
    border-radius: 16px;
  }

  .brand {
    gap: 8px;
    font-size: 15px;
  }

  .brand-mark {
    width: 32px;
    height: 32px;
  }

  .header-actions {
    gap: 0;
  }

  .header-control {
    height: 42px;
    padding-inline: 10px;
  }

  .support-link span {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
  }

  .hero {
    gap: 42px;
    padding: 124px 0 72px;
  }

  .product-label {
    margin-bottom: 16px;
    font-size: 12px;
  }

  .hero h1 {
    font-size: clamp(44px, 13vw, 62px);
    letter-spacing: -0.045em;
  }

  .hero-lead {
    font-size: 17px;
    line-height: 1.6;
  }

  .hero-preview {
    padding: 5px;
    border-radius: 18px;
  }

  .hero-preview img {
    border-radius: 13px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
    margin-top: 18px;
  }

  .button {
    width: 100%;
  }

  .features {
    padding: 80px 0;
  }

  .section-heading {
    margin-bottom: 32px;
  }

  .section-heading h2 {
    font-size: 40px;
  }

  .section-heading > p {
    font-size: 17px;
  }

  .feature-card {
    padding: 24px;
    border-radius: 20px;
  }

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

  .preview-card {
    border-radius: 20px;
  }

  .preview-card img {
    height: min(132vw, 580px);
  }

  .install {
    padding: 0 0 80px;
  }

  .install-panel {
    gap: 32px;
    padding: 32px 24px;
    border-radius: 24px;
  }

  .install-panel h2 {
    font-size: 38px;
  }

  .destination-badges {
    flex-direction: column;
    width: 100%;
  }

  .destination-badges a {
    width: min(224px, 100%);
  }

  .footer-inner {
    flex-direction: column;
    gap: 20px;
    align-items: flex-start;
    justify-content: center;
    padding: 28px 0;
  }

  .footer-links {
    flex-wrap: wrap;
    gap: 12px 20px;
  }
}

@media (max-width: 380px) {
  .brand > span:last-child {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
  }
}

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

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

  [data-reveal].reveal-pending,
  [data-reveal].reveal-pending.is-visible {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-transparency: reduce) {
  .nav-shell,
  .site-header.is-scrolled .nav-shell {
    background: var(--surface);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}

@media (prefers-contrast: more) {
  .nav-shell,
  .feature-card,
  .preview-card,
  .install-panel,
  .hero-preview {
    border-color: var(--text);
  }
}