* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --ink: #142927;
  --ink-soft: #26423d;
  --teal: #00a892;
  --teal-bright: #13d2b5;
  --teal-deep: #04bda3;
  --cyan: #28a9f2;
  --gold: #ffc83d;
  --bg: #f4fdfb;
  --surface: #ffffff;
  --muted: #5d706b;
  --line: #d9efea;
  --danger: #f43f5e;
  --shadow: 0 22px 50px rgba(15, 118, 110, 0.12);
  --shadow-soft: 0 10px 28px rgba(15, 118, 110, 0.08);
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--ink);
  font-family: "Segoe UI", "Microsoft YaHei UI", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  min-width: 320px;
  padding-bottom: 64px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

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

::selection {
  background: rgba(4, 189, 163, 0.24);
  color: var(--ink);
}

.icon {
  width: 1em;
  height: 1em;
  flex: none;
  stroke-width: 2;
}

.top-box {
  position: relative;
  z-index: 40;
}

.header-box {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
}

.header-shell,
.hidden-header-content {
  width: min(1180px, calc(100% - 48px));
  height: 76px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand img {
  width: 42px;
  height: 42px;
  object-fit: contain;
}

.brand-name {
  color: var(--ink);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.2;
  white-space: nowrap;
}

.header-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 34px;
}

.nav-link {
  color: var(--ink-soft);
  font-size: 15px;
  font-weight: 600;
  transition: color 0.2s ease;
}

.nav-link:hover {
  color: var(--teal-deep);
}

.header-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 42px;
  padding: 0 18px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  white-space: nowrap;
  box-shadow: 0 8px 18px rgba(20, 41, 39, 0.14);
  transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.header-cta:hover {
  background: var(--teal-deep);
  box-shadow: 0 10px 22px rgba(4, 189, 163, 0.22);
  transform: translateY(-1px);
}

.hidden-header-box {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(217, 239, 234, 0.8);
}

.hidden-header-box.active {
  box-shadow: 0 12px 34px rgba(20, 41, 39, 0.1);
}

.hero {
  padding: 142px 24px 88px;
  background:
    linear-gradient(rgba(4, 189, 163, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(4, 189, 163, 0.045) 1px, transparent 1px),
    linear-gradient(115deg, #eefbf9 0%, #ffffff 52%, #dff8f3 100%);
  background-size: 32px 32px, 32px 32px, auto;
  overflow: hidden;
}

.hero-shell {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(420px, 0.98fr);
  align-items: center;
  gap: 64px;
}

.hero h1 {
  color: var(--ink);
  font-size: clamp(38px, 4.6vw, 56px);
  font-weight: 800;
  line-height: 1.1;
}

.hero-lead {
  max-width: 620px;
  margin-top: 24px;
  color: var(--muted);
  font-size: clamp(16px, 1.7vw, 20px);
  line-height: 1.8;
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
  list-style: none;
}

.hero-points li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid rgba(20, 41, 39, 0.08);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  color: var(--ink-soft);
  font-size: 14px;
  font-weight: 600;
  box-shadow: 0 6px 18px rgba(15, 118, 110, 0.05);
}

.hero-points .icon {
  width: 18px;
  height: 18px;
  color: var(--teal-deep);
}

.download-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  min-height: 76px;
  padding: 14px 30px;
  border-radius: 18px;
  background: linear-gradient(90deg, var(--teal-deep), var(--teal-bright));
  color: #fff;
  box-shadow: 0 18px 38px rgba(4, 189, 163, 0.28);
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease, filter 0.2s ease;
}

.download-btn::before {
  content: "";
  position: absolute;
  top: -60%;
  bottom: -60%;
  left: -40%;
  width: 34%;
  background: linear-gradient(90deg, rgba(255, 255, 255, 0), rgba(255, 255, 255, 0.38), rgba(255, 255, 255, 0));
  transform: skewX(-22deg) translateX(-80%);
  transition: transform 0.5s ease;
  pointer-events: none;
}

.download-btn:hover {
  filter: saturate(1.08);
  box-shadow: 0 22px 44px rgba(4, 189, 163, 0.34);
  transform: translateY(-2px);
}

.download-btn:hover::before {
  transform: skewX(-22deg) translateX(420%);
}

.download-btn .icon-download {
  width: 28px;
  height: 28px;
}

.download-label {
  font-size: 22px;
  font-weight: 800;
  line-height: 1;
}

.download-btn small {
  display: block;
  font-size: 12px;
  font-weight: 600;
  line-height: 1;
  opacity: 0.88;
  margin-top: 5px;
}

.hero .download-btn {
  margin-top: 34px;
}

.hero-visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 520px;
}

.hero-image {
  width: min(100%, 540px);
  max-height: 620px;
  object-fit: contain;
  filter: drop-shadow(0 30px 46px rgba(4, 189, 163, 0.2));
}

.trust-strip {
  background: linear-gradient(90deg, #effbf9 0%, #e6f8ff 100%);
  color: var(--teal-deep);
  border-top: 1px solid rgba(4, 189, 163, 0.14);
  border-bottom: 1px solid rgba(4, 189, 163, 0.14);
}

.trust-shell {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.trust-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2px 14px;
  align-items: center;
  min-height: 104px;
  padding: 20px 28px;
  border-right: 1px solid rgba(4, 189, 163, 0.16);
}

.trust-item:last-child {
  border-right: 0;
}

.trust-item strong {
  grid-row: 1 / 3;
  color: var(--teal-deep);
  font-size: 30px;
  font-weight: 800;
}

.trust-item span {
  color: #0b6e63;
  font-size: 17px;
  font-weight: 700;
}

.trust-item small {
  color: #6f8f8a;
  font-size: 13px;
}

.features-section,
.module-section,
.faq-section,
.final-download {
  padding: 92px 24px;
}

.section-head {
  width: min(760px, 100%);
  margin: 0 auto 58px;
  text-align: center;
}

.section-head h2 {
  color: var(--ink);
  font-size: clamp(28px, 3.5vw, 42px);
  font-weight: 800;
  line-height: 1.25;
}

.section-head p {
  margin-top: 12px;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
}

.features-section {
  background: #fff;
}

.feature-row {
  width: min(1180px, 100%);
  margin: 0 auto 72px;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  align-items: center;
  gap: 64px;
}

.feature-row:last-child {
  margin-bottom: 0;
}

.feature-row.reverse .feature-media {
  order: 2;
}

.feature-row.reverse .feature-copy {
  order: 1;
}

.feature-media {
  border-radius: 16px;
  overflow: hidden;
  background: #eefbf9;
  box-shadow: var(--shadow);
  border: 1px solid rgba(4, 189, 163, 0.12);
}

.feature-media img {
  width: 100%;
  height: auto;
}

.feature-tag {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: 13px;
  font-weight: 800;
}

.feature-copy h3 {
  margin-top: 16px;
  color: var(--ink);
  font-size: clamp(26px, 3vw, 36px);
  font-weight: 800;
  line-height: 1.3;
}

.feature-copy p {
  margin-top: 14px;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.85;
}

.feature-copy ul {
  display: grid;
  gap: 10px;
  margin-top: 22px;
  list-style: none;
}

.feature-copy li {
  position: relative;
  padding-left: 26px;
  color: var(--ink-soft);
  font-size: 15px;
  font-weight: 600;
}

.feature-copy li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 14px;
  height: 9px;
  border-left: 2px solid var(--teal-deep);
  border-bottom: 2px solid var(--teal-deep);
  transform: rotate(-45deg);
}

.module-section {
  background:
    linear-gradient(rgba(255, 255, 255, 0.72), rgba(255, 255, 255, 0.72)),
    linear-gradient(120deg, #eafcf8 0%, #f8fffd 46%, #e7f7ff 100%);
}

.module-grid {
  width: min(1180px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.module-card {
  min-height: 216px;
  padding: 26px;
  border: 1px solid rgba(217, 239, 234, 0.9);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: var(--shadow-soft);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.module-card:hover {
  transform: translateY(-4px);
  border-color: rgba(4, 189, 163, 0.35);
  box-shadow: var(--shadow);
}

.module-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 14px;
  color: #fff;
  box-shadow: 0 10px 22px rgba(15, 118, 110, 0.16);
}

.module-icon .icon {
  width: 24px;
  height: 24px;
}

.icon-teal {
  background: linear-gradient(135deg, #00b9a2, #14d3b8);
}

.icon-amber {
  background: linear-gradient(135deg, #ffc83d, #f59e0b);
}

.icon-cyan {
  background: linear-gradient(135deg, #28a9f2, #38bdf8);
}

.icon-rose {
  background: linear-gradient(135deg, #fb7185, #f43f5e);
}

.icon-blue {
  background: linear-gradient(135deg, #6366f1, #3b82f6);
}

.icon-green {
  background: linear-gradient(135deg, #10b981, #22d3ee);
}

.module-card h3 {
  margin-top: 18px;
  color: var(--ink);
  font-size: 20px;
  font-weight: 800;
}

.module-card p {
  margin-top: 8px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
}

.faq-section {
  background: #fff;
}

.faq-list {
  width: min(900px, 100%);
  margin: 0 auto;
  display: grid;
  gap: 16px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fbfefd;
  overflow: hidden;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.faq-item:hover {
  border-color: rgba(4, 189, 163, 0.3);
  box-shadow: var(--shadow-soft);
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 20px 24px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 800;
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  flex: none;
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: rgba(4, 189, 163, 0.12);
  color: var(--teal-deep);
  font-size: 22px;
  font-weight: 600;
  transition: transform 0.2s ease, background 0.2s ease;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
  background: var(--teal-deep);
  color: #fff;
}

.faq-item p {
  padding: 0 24px 22px;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.85;
}

.final-download {
  background: linear-gradient(135deg, #f4fdfb 0%, #edf8ff 100%);
  color: var(--ink);
  border-top: 1px solid rgba(4, 189, 163, 0.14);
  border-bottom: 1px solid rgba(4, 189, 163, 0.14);
  text-align: center;
}

.final-shell {
  width: min(820px, 100%);
  margin: 0 auto;
}

.final-shell > img {
  width: 96px;
  height: 96px;
  margin: 0 auto;
  object-fit: contain;
  filter: drop-shadow(0 16px 30px rgba(4, 189, 163, 0.14));
}

.final-shell h2 {
  margin-top: 18px;
  color: var(--ink);
  font-size: clamp(30px, 4vw, 44px);
  font-weight: 800;
}

.final-shell p {
  max-width: 640px;
  margin: 14px auto 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.85;
}

.final-shell .download-btn {
  margin-top: 30px;
  background: linear-gradient(90deg, var(--teal-deep), var(--teal-bright));
  color: #fff;
  box-shadow: 0 18px 38px rgba(4, 189, 163, 0.24);
}

.final-shell .download-btn::before {
  background: linear-gradient(90deg, rgba(255, 255, 255, 0), rgba(255, 255, 255, 0.34), rgba(255, 255, 255, 0));
}

.security-row {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px 22px;
  margin-top: 22px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 600;
}

.security-row span::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--teal-deep);
  vertical-align: middle;
}

.footer {
  padding: 36px 24px 42px;
  background: var(--ink);
  color: rgba(255, 255, 255, 0.64);
  text-align: center;
}

.footer p {
  max-width: 980px;
  margin: 0 auto;
  font-size: 13px;
  line-height: 1.8;
}

.footer p + p {
  margin-top: 8px;
}

.bottom-nav {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 50;
  height: 64px;
  display: flex;
  align-items: center;
  background: rgba(20, 41, 39, 0.96);
  color: #fff;
  transform: translateY(100%);
  opacity: 0;
  transition: transform 0.28s ease, opacity 0.28s ease;
}

.bottom-nav.show {
  transform: translateY(0);
  opacity: 1;
}

.nav-links {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  font-size: 14px;
}

.nav-links a {
  color: #fff;
  font-weight: 600;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--teal-bright);
}

.nav-links span {
  color: rgba(255, 255, 255, 0.3);
}

.download-progress-panel {
  position: fixed;
  inset: 0;
  z-index: 3000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(10, 18, 38, 0.58);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}

.download-progress-panel.show {
  opacity: 1;
  visibility: visible;
}

.download-progress-card {
  width: min(520px, calc(100% - 40px));
  padding: 42px 40px 36px;
  border-radius: 20px;
  background: #fff;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.22);
  text-align: center;
}

.download-progress-icon {
  width: 88px;
  height: 88px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 22px;
  background: linear-gradient(180deg, #eafbf8 0%, #d9f7f0 100%);
}

.download-progress-icon img {
  max-width: 72px;
  max-height: 72px;
  object-fit: contain;
}

.download-progress-title {
  color: var(--ink);
  font-size: 26px;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 8px;
}

.download-progress-desc {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 26px;
}

.download-progress-bar {
  width: 100%;
  height: 14px;
  border-radius: 999px;
  overflow: hidden;
  background: #edf4f2;
}

.download-progress-bar span {
  display: block;
  width: 0;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--teal-deep), var(--teal-bright));
  transition: width 0.2s ease;
}

.download-progress-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  margin-top: 14px;
  color: var(--muted);
  font-size: 14px;
}

.download-progress-percent {
  color: var(--teal-deep);
  font-size: 22px;
  font-weight: 800;
}

@media (max-width: 1080px) {
  .header-nav {
    display: none;
  }

  .hero-shell {
    grid-template-columns: minmax(0, 1fr) minmax(340px, 0.9fr);
    gap: 36px;
  }

  .hero-visual {
    min-height: 440px;
  }

  .feature-row {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 36px;
  }

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

@media (max-width: 820px) {
  .header-shell,
  .hidden-header-content {
    width: min(100% - 32px, 1180px);
    height: 66px;
  }

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

  .brand-name {
    font-size: 17px;
  }

  .hero {
    padding: 120px 20px 64px;
  }

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

  .hero-visual {
    order: -1;
    min-height: 0;
    padding: 12px 0 44px;
  }

  .hero-image {
    width: min(100%, 420px);
  }

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

  .trust-item {
    border-bottom: 1px solid rgba(4, 189, 163, 0.14);
  }

  .trust-item:nth-child(2) {
    border-right: 0;
  }

  .trust-item:nth-child(3),
  .trust-item:nth-child(4) {
    border-bottom: 0;
  }

  .features-section,
  .module-section,
  .faq-section,
  .final-download {
    padding: 64px 20px;
  }

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

  .feature-row.reverse .feature-media {
    order: 1;
  }

  .feature-row.reverse .feature-copy {
    order: 2;
  }

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

  .final-shell .download-btn {
    width: min(100%, 360px);
  }
}

@media (max-width: 520px) {
  .header-cta {
    width: 42px;
    padding: 0;
    font-size: 0;
  }

  .header-cta .icon {
    width: 20px;
    height: 20px;
  }

  .hero h1 {
    font-size: 36px;
  }

  .download-btn {
    width: 100%;
  }

  .trust-item {
    padding: 16px 12px;
  }

  .trust-item strong {
    font-size: 24px;
  }

  .feature-copy h3 {
    font-size: 26px;
  }

  .section-head h2 {
    font-size: 28px;
  }

  .bottom-nav {
    height: 56px;
  }

  .nav-links {
    gap: 8px;
    font-size: 12px;
  }
}

@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;
  }
}