:root {
  --ink: #17211f;
  --muted: #59635f;
  --line: #d7dfdb;
  --paper: #ffffff;
  --soft: #f2f7f4;
  --brand: #0b8c7b;
  --brand-dark: #07695d;
  --aqua: #19c9c4;
  --coral: #d96256;
  --lavender: #eee8f7;
  --header-height: 72px;
  --content-width: 1180px;
  color-scheme: light;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 18px);
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.65;
}

body.modal-open {
  overflow: hidden;
}

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

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

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

button {
  font: inherit;
}

:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--aqua) 70%, white);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  z-index: 1000;
  top: 10px;
  left: 10px;
  transform: translateY(-150%);
  padding: 8px 14px;
  background: var(--ink);
  color: white;
}

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

.site-header,
.legal-header {
  position: sticky;
  z-index: 100;
  top: 0;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(12px);
}

.site-header.is-scrolled,
.legal-header {
  border-bottom-color: var(--line);
}

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

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  font-size: 20px;
  font-weight: 800;
}

.brand img {
  width: 42px;
  height: 42px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 26px;
  font-size: 15px;
  font-weight: 600;
}

.site-nav > a:not(.nav-download) {
  position: relative;
}

.site-nav > a:not(.nav-download)::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: -8px;
  left: 0;
  height: 2px;
  transform: scaleX(0);
  background: var(--brand);
  transition: transform 180ms ease;
}

.site-nav > a:hover::after {
  transform: scaleX(1);
}

.nav-download {
  padding: 9px 16px;
  background: var(--ink);
  color: white;
  border-radius: 6px;
}

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

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

.hero {
  position: relative;
  min-height: 600px;
  height: min(760px, calc(100svh - var(--header-height) - 36px));
  overflow: hidden;
  background: var(--soft);
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  position: relative;
  z-index: 2;
  width: min(calc(100% - 40px), var(--content-width));
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
}

.hero-copy {
  width: min(56%, 620px);
  padding-bottom: 28px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--brand-dark);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1,
.legal-article h1 {
  margin: 0;
  font-size: clamp(56px, 8vw, 106px);
  line-height: 1.02;
  letter-spacing: 0;
}

.hero-lead {
  margin: 22px 0 8px;
  font-size: clamp(24px, 3vw, 38px);
  font-weight: 750;
  line-height: 1.25;
}

.hero-description {
  max-width: 570px;
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button {
  min-height: 50px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 12px 22px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-weight: 750;
  line-height: 1.3;
  transition: transform 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  background: var(--brand);
  color: white;
}

.button-primary:hover {
  background: var(--brand-dark);
}

.button-secondary {
  border-color: #a8b5b0;
  background: rgba(255, 255, 255, 0.7);
}

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

.hero-visual {
  position: absolute;
  z-index: 1;
  inset: 0;
  width: min(calc(100% - 40px), var(--content-width));
  margin: auto;
  pointer-events: none;
}

.hero-phone {
  position: absolute;
  object-fit: contain;
  filter: drop-shadow(0 20px 24px rgba(23, 33, 31, 0.12));
}

.hero-phone-primary {
  right: -30px;
  bottom: -210px;
  width: 410px;
  transform: rotate(2deg);
}

.hero-phone-secondary {
  right: 295px;
  bottom: -250px;
  width: 310px;
  opacity: 0.78;
  transform: rotate(-5deg);
}

.hero-next {
  position: absolute;
  z-index: 3;
  bottom: 18px;
  left: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  color: var(--muted);
  font-size: 12px;
  transform: translateX(-50%);
}

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

.section-inner-wide {
  width: min(calc(100% - 32px), 1320px);
}

.feature-section,
.screenshots-section,
.contact-section {
  padding: 104px 0;
}

.section-heading {
  max-width: 690px;
}

.section-heading h2,
.download-inner h2,
.contact-copy h2 {
  margin: 0;
  font-size: clamp(34px, 4vw, 56px);
  line-height: 1.16;
  letter-spacing: 0;
}

.section-heading > p:last-child,
.download-inner p,
.contact-copy > p {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 18px;
}

.feature-list {
  margin-top: 62px;
  border-top: 1px solid var(--line);
}

.feature-item {
  display: grid;
  grid-template-columns: 80px minmax(0, 1fr);
  gap: 28px;
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.feature-number {
  color: var(--coral);
  font-size: 16px;
  font-weight: 800;
}

.feature-item h3 {
  margin: 0;
  font-size: 24px;
}

.feature-item p {
  max-width: 690px;
  margin: 7px 0 0;
  color: var(--muted);
}

.screenshots-section {
  overflow: hidden;
  background: #f7f4fb;
}

.screenshot-heading {
  width: min(calc(100% - 8px), 690px);
  margin: 0 auto 50px;
  text-align: center;
}

.screenshot-track {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  align-items: start;
}

.screenshot-button {
  min-width: 0;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: zoom-in;
  transition: transform 180ms ease;
}

.screenshot-button:hover {
  transform: translateY(-7px);
}

.screenshot-button img {
  width: 100%;
  max-height: 690px;
  object-fit: contain;
}

.download-section {
  padding: 82px 0;
  background: var(--ink);
  color: white;
}

.download-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}

.download-inner > div {
  max-width: 720px;
}

.download-inner p {
  color: #cbd3d0;
}

.eyebrow-light {
  color: #60ddd1;
}

.contact-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  align-items: center;
  gap: clamp(54px, 9vw, 130px);
}

.contact-copy {
  max-width: 650px;
}

.wechat-id {
  max-width: 520px;
  margin-top: 28px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 16px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.wechat-id span {
  color: var(--muted);
}

.wechat-id strong {
  font-size: 20px;
}

.copy-button {
  min-width: 64px;
  min-height: 40px;
  padding: 7px 14px;
  border: 1px solid var(--brand);
  border-radius: 5px;
  background: transparent;
  color: var(--brand-dark);
  font-weight: 700;
  cursor: pointer;
}

.contact-note {
  font-size: 15px !important;
}

.copy-status {
  min-height: 26px;
  margin-top: 6px !important;
  color: var(--brand-dark) !important;
  font-size: 14px !important;
}

.qr-wrap {
  aspect-ratio: 1 / 1;
  padding: 16px;
  border: 1px solid var(--line);
  background: white;
}

.qr-wrap img {
  width: 100%;
  height: 100%;
  aspect-ratio: 1 / 1;
  object-fit: contain;
}

.site-footer {
  padding: 34px 0;
  border-top: 1px solid var(--line);
  background: var(--soft);
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
  color: var(--muted);
  font-size: 14px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--ink);
  font-weight: 800;
}

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

.footer-links a:hover,
.back-link:hover,
.legal-footer a:hover {
  color: var(--brand-dark);
}

.footer-inner > p {
  margin: 0;
  text-align: right;
}

.lightbox[hidden] {
  display: none;
}

.lightbox {
  position: fixed;
  z-index: 500;
  inset: 0;
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr) 72px;
  align-items: center;
  padding: 30px;
  background: rgba(10, 15, 14, 0.94);
}

.lightbox-stage {
  height: calc(100vh - 60px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.lightbox-stage img {
  max-width: 100%;
  max-height: calc(100% - 36px);
  object-fit: contain;
}

.lightbox-stage p {
  margin: 0;
  color: white;
}

.lightbox-close,
.lightbox-arrow {
  width: 52px;
  height: 52px;
  border: 1px solid rgba(255, 255, 255, 0.45);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: white;
  font-size: 34px;
  line-height: 1;
  cursor: pointer;
}

.lightbox-close {
  position: absolute;
  top: max(22px, env(safe-area-inset-top));
  right: 24px;
}

.lightbox-arrow {
  justify-self: center;
}

.legal-body {
  background: var(--soft);
}

.back-link {
  color: var(--brand-dark);
  font-weight: 700;
}

.legal-main {
  padding: 64px 20px 90px;
}

.legal-article {
  width: min(100%, 820px);
  margin: 0 auto;
  padding: clamp(30px, 6vw, 68px);
  border: 1px solid var(--line);
  background: white;
}

.legal-article h1 {
  font-size: clamp(42px, 7vw, 70px);
}

.legal-article .legal-date {
  margin: 28px 0 48px;
  color: var(--muted);
}

.legal-article section {
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.legal-article h2 {
  margin: 0 0 8px;
  font-size: 22px;
}

.legal-article p {
  margin: 0;
  color: #424d49;
}

.legal-footer {
  display: flex;
  justify-content: center;
  gap: 28px;
  padding: 28px 20px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}

@media (max-width: 1040px) {
  .hero-copy {
    width: 58%;
  }

  .hero-phone-primary {
    right: -50px;
    width: 360px;
  }

  .hero-phone-secondary {
    right: 245px;
    width: 260px;
    opacity: 0.5;
  }

  .screenshot-track {
    display: flex;
    gap: 14px;
    padding: 0 4px 18px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    scrollbar-width: thin;
  }

  .screenshot-button {
    flex: 0 0 clamp(230px, 31vw, 300px);
    scroll-snap-align: center;
  }
}

@media (max-width: 820px) {
  :root {
    --header-height: 64px;
  }

  .header-inner,
  .section-inner,
  .footer-inner {
    width: min(calc(100% - 32px), var(--content-width));
  }

  .menu-button {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: calc(100% - 1px);
    right: 0;
    left: 0;
    display: none;
    padding: 14px 20px 20px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border-bottom: 1px solid var(--line);
    background: white;
    box-shadow: 0 12px 22px rgba(23, 33, 31, 0.08);
  }

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

  .site-nav a {
    padding: 12px 4px;
  }

  .site-nav > a:not(.nav-download)::after {
    display: none;
  }

  .nav-download {
    margin-top: 8px;
    padding: 11px 14px !important;
    text-align: center;
  }

  .menu-button.is-open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .menu-button.is-open span:nth-child(2) {
    opacity: 0;
  }

  .menu-button.is-open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero {
    min-height: 600px;
    height: min(760px, calc(100svh - var(--header-height) - 30px));
  }

  .hero-inner {
    align-items: flex-start;
    padding-top: 62px;
  }

  .hero-copy {
    width: 54%;
    padding: 0;
  }

  .hero h1 {
    font-size: clamp(58px, 13vw, 90px);
  }

  .hero-description {
    font-size: 16px;
  }

  .hero-phone-primary {
    right: -90px;
    bottom: -230px;
    width: 340px;
    opacity: 0.88;
  }

  .hero-phone-secondary {
    display: none;
  }

  .feature-section,
  .screenshots-section,
  .contact-section {
    padding: 78px 0;
  }

  .download-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 30px;
  }

  .contact-inner {
    grid-template-columns: 1fr 280px;
    gap: 42px;
  }

  .footer-inner {
    grid-template-columns: 1fr auto;
  }

  .footer-links {
    grid-column: 1 / -1;
    grid-row: 2;
  }
}

@media (max-width: 600px) {
  .brand {
    font-size: 18px;
  }

  .brand img {
    width: 36px;
    height: 36px;
  }

  .hero {
    min-height: 560px;
    height: min(680px, calc(100svh - var(--header-height) - 24px));
  }

  .hero-inner {
    padding-top: 42px;
  }

  .hero-copy {
    width: 100%;
  }

  .hero h1 {
    font-size: clamp(54px, 18vw, 76px);
  }

  .hero-lead {
    max-width: 360px;
    margin-top: 16px;
    font-size: 25px;
  }

  .hero-description {
    max-width: 350px;
    padding-right: 20px;
  }

  .hero-actions {
    margin-top: 22px;
  }

  .button {
    min-height: 48px;
    padding: 11px 16px;
  }

  .button-secondary {
    background: rgba(255, 255, 255, 0.84);
  }

  .hero-phone-primary {
    right: -78px;
    bottom: -360px;
    width: 315px;
    opacity: 0.7;
  }

  .hero-next {
    display: none;
  }

  .section-heading h2,
  .download-inner h2,
  .contact-copy h2 {
    font-size: 36px;
  }

  .section-heading > p:last-child,
  .download-inner p,
  .contact-copy > p {
    font-size: 16px;
  }

  .feature-list {
    margin-top: 42px;
  }

  .feature-item {
    grid-template-columns: 44px minmax(0, 1fr);
    gap: 14px;
    padding: 24px 0;
  }

  .feature-item h3 {
    font-size: 21px;
  }

  .screenshot-heading {
    text-align: left;
  }

  .screenshot-track {
    margin-right: -16px;
  }

  .screenshot-button {
    flex-basis: min(76vw, 280px);
  }

  .download-section {
    padding: 66px 0;
  }

  .button-light {
    width: 100%;
  }

  .contact-inner {
    grid-template-columns: 1fr;
  }

  .qr-wrap {
    width: min(100%, 320px);
    margin: 0 auto;
  }

  .wechat-id {
    grid-template-columns: 1fr auto;
  }

  .wechat-id span {
    grid-column: 1 / -1;
  }

  .footer-inner {
    display: flex;
    align-items: flex-start;
    flex-direction: column;
    gap: 16px;
  }

  .footer-links {
    flex-wrap: wrap;
    gap: 10px 22px;
  }

  .footer-inner > p {
    text-align: left;
  }

  .lightbox {
    grid-template-columns: 48px minmax(0, 1fr) 48px;
    padding: 16px 8px;
  }

  .lightbox-stage {
    height: calc(100vh - 32px);
  }

  .lightbox-close,
  .lightbox-arrow {
    width: 42px;
    height: 42px;
    font-size: 28px;
  }

  .lightbox-close {
    right: 12px;
  }

  .legal-main {
    padding: 24px 12px 60px;
  }

  .legal-article {
    padding: 28px 20px;
  }

  .legal-date {
    margin-bottom: 34px;
  }
}

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

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