:root {
  --navy: #071b3d;
  --navy-2: #102d61;
  --blue-soft: #eef4ff;
  --blue-wash: oklch(96% 0.03 255);
  --gold: #f4b63d;
  --gold-hover: #ffc34f;
  --gold-deep: #b97800;
  --gold-wash: oklch(96.5% 0.055 84);
  --teal: oklch(58% 0.11 178);
  --teal-deep: oklch(38% 0.075 178);
  --teal-wash: oklch(95.5% 0.035 178);
  --ink: #16213a;
  --muted: #5f6b7d;
  --meta: #798497;
  --line: #e7e9ee;
  --surface: #f7f9fc;
  --success: #2f8f52;
  --danger: #b83b32;
  --font: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Noto Sans CJK SC", "Segoe UI", sans-serif;
  --container: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

body, button, a { font-size: 16px; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button { font-family: inherit; }

:focus-visible {
  outline: 3px solid rgba(30, 91, 255, .34);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: -60px;
  z-index: 100;
  padding: 10px 14px;
  border-radius: 8px;
  color: #fff;
  background: var(--navy);
}
.skip-link:focus { top: 16px; }

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

.site-header {
  z-index: 40;
  height: 76px;
  background: #fff;
  border-bottom: 1px solid var(--line);
}

.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

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

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 11px;
}

.brand-name {
  display: block;
  color: var(--navy);
  font-size: 20px;
  font-weight: 750;
  line-height: 1.1;
}

.brand-tagline {
  display: block;
  margin-top: 4px;
  color: var(--meta);
  font-size: 10px;
  letter-spacing: .08em;
}

.nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 30px;
}

.nav a {
  color: #536074;
  font-size: 14px;
  font-weight: 600;
}
.nav a:hover { color: var(--navy); }

.header-download,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 11px;
  font-weight: 700;
  transition: transform 160ms ease-out, background-color 160ms ease-out, color 160ms ease-out;
}

.header-download {
  min-height: 42px;
  color: #fff;
  background: var(--navy);
  font-size: 14px;
  white-space: nowrap;
}

.button:hover,
.header-download:hover { transform: translateY(-1px); }

.button-primary { color: var(--navy); background: var(--gold); }
.button-primary:hover { background: var(--gold-hover); }
.button-secondary { color: var(--navy); border: 1px solid #ccd3df; background: #fff; }
.button-secondary:hover { border-color: var(--navy); }
.button-on-dark { color: var(--navy); background: #fff; }

.os-mark {
  min-width: 29px;
  padding: 3px 5px;
  border-radius: 5px;
  border: 1px solid currentColor;
  font-size: 9px;
  font-weight: 800;
  line-height: 1;
  text-align: center;
}

.hero {
  overflow: hidden;
  background:
    radial-gradient(circle at 92% 12%, oklch(89% 0.07 255), transparent 29%),
    linear-gradient(105deg, oklch(98.5% 0.01 255) 0 54%, oklch(95% 0.04 255) 54% 100%);
}

.hero-grid {
  min-height: 650px;
  padding-block: 68px 54px;
  display: grid;
  grid-template-columns: .84fr 1.16fr;
  gap: 40px;
  align-items: center;
}

.hero-label {
  margin: 0 0 20px;
  display: flex;
  align-items: center;
  gap: 10px;
  color: #56647a;
  font-size: 14px;
  font-weight: 650;
}

.hero-label::before {
  content: "";
  width: 28px;
  height: 2px;
  background: var(--gold);
}

.hero h1 {
  margin: 0;
  color: var(--navy);
  font-size: clamp(3.1rem, 4.3vw, 3.875rem);
  font-weight: 780;
  line-height: 1.07;
  letter-spacing: -.035em;
  text-wrap: balance;
}

.hero h1 span { color: var(--gold-deep); }

.hero-copy > p {
  max-width: 580px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.75;
  text-wrap: pretty;
}

.hero-actions {
  margin-top: 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero-meta {
  margin: 16px 0 0;
  display: flex;
  align-items: center;
  gap: 9px;
  color: var(--meta);
  font-size: 13px;
  line-height: 1.5;
}

.status-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 7px;
  border-radius: 50%;
  background: var(--success);
}

.hero-visual {
  position: relative;
  margin-right: -52px;
  padding: 16px 0 0;
}

.hero-visual::before {
  content: "";
  position: absolute;
  width: min(430px, 78%);
  aspect-ratio: 1;
  right: -25px;
  top: -24px;
  border-radius: 50%;
  background: oklch(91% 0.06 255);
}

.product-window {
  position: relative;
  z-index: 2;
  overflow: hidden;
  border-radius: 16px;
  background: #fff;
  box-shadow: 0 28px 70px rgba(14, 38, 83, .20), 0 6px 14px rgba(14, 38, 83, .09);
  transform: none;
}

.product-window img {
  width: 100%;
  height: auto;
  aspect-ratio: 1600 / 1030;
  object-fit: contain;
}

.reply-note {
  position: relative;
  z-index: 3;
  width: min(360px, 78%);
  margin: 14px 4px 0 auto;
  padding: 14px 16px;
  border-radius: 14px;
  color: #fff;
  background: var(--navy);
  box-shadow: 0 12px 28px rgba(7, 27, 61, .22);
  font-size: 13px;
  line-height: 1.55;
}

.reply-note small {
  display: block;
  margin-top: 7px;
  color: #a9d7b9;
  font-size: 10px;
}

.trust-bar {
  padding-block: 14px;
  background: oklch(97.5% 0.014 255);
}
.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.trust-item {
  min-height: 92px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 18px 20px;
  border-radius: 12px;
}
.trust-item:nth-child(1) { background: var(--blue-wash); }
.trust-item:nth-child(2) { background: var(--gold-wash); }
.trust-item:nth-child(3) { background: var(--teal-wash); }

.trust-check {
  width: 24px;
  height: 24px;
  flex: 0 0 24px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--navy);
  font-size: 13px;
  font-weight: 800;
}
.trust-item:nth-child(2) .trust-check { color: var(--navy); background: var(--gold); }
.trust-item:nth-child(3) .trust-check { background: var(--teal); }

.trust-item strong {
  display: block;
  margin-bottom: 4px;
  color: var(--navy);
  font-size: 15px;
}
.trust-item:nth-child(2) strong { color: #774a00; }
.trust-item:nth-child(3) strong { color: var(--teal-deep); }
.trust-item p { margin: 0; color: #506078; font-size: 12px; line-height: 1.55; }
.trust-item:nth-child(2) p { color: #765b2a; }
.trust-item:nth-child(3) p { color: oklch(41% 0.045 178); }

.proof-strip { color: #fff; background: var(--navy); }
.proof-inner {
  min-height: 176px;
  display: grid;
  grid-template-columns: .72fr 1.28fr;
  gap: 60px;
  align-items: center;
  padding-block: 28px;
}

.proof-copy h2 {
  margin: 0;
  font-size: clamp(1.65rem, 2.7vw, 2.2rem);
  line-height: 1.25;
  letter-spacing: -.025em;
  text-wrap: balance;
}
.proof-copy p { margin: 8px 0 0; color: #b4c0d3; font-size: 13px; line-height: 1.6; }

.message-flow { display: flex; flex-direction: column; gap: 10px; }
.flow-row {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr) auto;
  align-items: center;
  gap: 12px;
}
.flow-time { color: #8496b3; font-size: 11px; }
.flow-text { padding: 11px 14px; border-radius: 9px; background: #112f63; font-size: 13px; }
.flow-state { color: #9ed4ad; font-size: 11px; white-space: nowrap; }

.section { padding-block: clamp(70px, 9vw, 112px); }
#features {
  padding-block: clamp(52px, 6vw, 76px);
  background: oklch(96.5% 0.045 84);
}
#features .section-heading {
  max-width: 680px;
  margin-bottom: 32px;
}
#features .section-heading h2 { font-size: clamp(1.9rem, 3vw, 2.7rem); }
#features .section-heading p { margin-top: 12px; font-size: 16px; line-height: 1.7; }
.section-heading {
  max-width: 720px;
  margin-bottom: 48px;
}
.section-heading h2 {
  margin: 0;
  color: var(--navy);
  font-size: clamp(2rem, 4vw, 3.35rem);
  line-height: 1.15;
  letter-spacing: -.035em;
  text-wrap: balance;
}
.section-heading p {
  max-width: 660px;
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.75;
}

.feature-list { border-top: 1px solid var(--line); }
.feature-row {
  display: grid;
  grid-template-columns: 64px .8fr 1.2fr;
  gap: 24px;
  align-items: start;
  padding-block: 22px;
  border-bottom: 1px solid var(--line);
}
.feature-number { color: var(--gold-deep); font-size: 14px; font-weight: 750; }
.feature-row h3 { margin: 0; color: var(--navy); font-size: 20px; line-height: 1.35; }
.feature-row p { max-width: 650px; margin: 0; color: var(--muted); font-size: 15px; line-height: 1.65; }

.how-section { background: oklch(95.5% 0.026 255); }
.steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  border-block: 1px solid #dfe4ec;
}
.step { padding: 28px 24px; }
.step + .step { border-left: 1px solid #dfe4ec; }
.step-number {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--navy);
  background: var(--gold);
  font-size: 13px;
  font-weight: 800;
}
.step h3 { margin: 20px 0 8px; color: var(--navy); font-size: 18px; }
.step p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.7; }
.section-action { margin-top: 28px; }

.download-section {
  padding-block: 68px;
  color: var(--navy);
  background: var(--gold);
}
.download-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}
.download-copy h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.2rem); letter-spacing: -.035em; line-height: 1.12; }
.download-copy p { margin: 14px 0 0; max-width: 620px; line-height: 1.7; }
.download-actions { display: flex; gap: 12px; flex-shrink: 0; }
.download-actions .button-secondary { background: transparent; border-color: rgba(7, 27, 61, .45); }

.site-footer { padding-block: 34px; color: #5f6d83; background: oklch(96.5% 0.016 255); border-top: 1px solid #dce4f2; }
.footer-inner { display: flex; align-items: flex-start; justify-content: space-between; gap: 30px; }
.footer-brand { color: var(--navy); font-weight: 750; }
.footer-copy { margin: 7px 0 0; font-size: 12px; line-height: 1.6; }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 20px; font-size: 13px; }
.footer-links a:hover { color: var(--navy); }

/* Guide and privacy pages */
.page-hero { padding-block: 72px 58px; background: var(--surface); border-bottom: 1px solid var(--line); }
.page-hero h1 { margin: 0; color: var(--navy); font-size: clamp(2.5rem, 5vw, 4.25rem); line-height: 1.1; letter-spacing: -.035em; }
.page-hero p { max-width: 720px; margin: 20px 0 0; color: var(--muted); font-size: 18px; line-height: 1.75; }
.guide-layout { display: grid; grid-template-columns: 220px minmax(0, 760px); gap: 72px; align-items: start; padding-block: 68px 100px; }
.guide-nav { position: sticky; top: 108px; display: flex; flex-direction: column; gap: 12px; }
.guide-nav a { color: #667287; font-size: 14px; }
.guide-nav a:hover { color: var(--navy); }
.guide-article section { scroll-margin-top: 105px; padding-bottom: 52px; }
.guide-article section + section { padding-top: 52px; border-top: 1px solid var(--line); }
.guide-article h2 { margin: 0 0 18px; color: var(--navy); font-size: 30px; line-height: 1.25; }
.guide-article h3 { margin: 28px 0 10px; color: var(--navy); font-size: 19px; }
.guide-article p, .guide-article li { color: var(--muted); line-height: 1.8; }
.guide-article ol, .guide-article ul { margin: 0; padding-left: 22px; }
.guide-article li + li { margin-top: 8px; }
.guide-note { margin-top: 20px; padding: 16px 18px; border-radius: 10px; background: var(--blue-soft); color: #42516a; line-height: 1.7; }
.guide-downloads { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.privacy-main { max-width: 780px; padding-block: 68px 100px; }
.privacy-main h2 { margin: 44px 0 14px; color: var(--navy); font-size: 26px; }
.privacy-main h2:first-child { margin-top: 0; }
.privacy-main p, .privacy-main li { color: var(--muted); line-height: 1.85; }
.privacy-main ul { padding-left: 22px; }

@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; padding-top: 62px; }
  .hero-copy { max-width: 760px; }
  .hero-visual { width: min(100%, 780px); margin-inline: auto; padding-left: 0; }
  .trust-grid { grid-template-columns: 1fr; }
  .proof-inner { grid-template-columns: 1fr; gap: 22px; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .step:nth-child(odd) { border-left: 0; }
  .step:nth-child(n+3) { border-top: 1px solid #dfe4ec; }
  .download-inner { align-items: flex-start; flex-direction: column; }
  .guide-layout { grid-template-columns: 1fr; gap: 36px; }
  .guide-nav { position: static; flex-direction: row; flex-wrap: wrap; padding-bottom: 24px; border-bottom: 1px solid var(--line); }
}

@media (max-width: 760px) {
  .container { width: min(calc(100% - 30px), var(--container)); }
  .site-header { height: 68px; }
  .brand-tagline { display: none; }
  .brand img { width: 36px; height: 36px; }
  .brand-name { font-size: 18px; }
  .nav { display: none; }
  .header-download { padding-inline: 14px; }
  .hero-grid { min-height: auto; padding-block: 52px 48px; gap: 34px; }
  .hero h1 { font-size: clamp(2.6rem, 12vw, 3.75rem); }
  .hero-copy > p { font-size: 16px; }
  .hero-visual::before { right: -90px; }
  .reply-note { width: min(340px, 82vw); }
  .proof-inner { padding-block: 25px; }
  .flow-row { grid-template-columns: 40px minmax(0, 1fr); }
  .flow-state { display: none; }
  #features .feature-row { grid-template-columns: 44px 1fr; gap: 10px 16px; padding-block: 20px; }
  #features .feature-row p { grid-column: 2; }
  .download-actions { width: 100%; flex-direction: column; }
  .download-actions .button { width: 100%; }
  .footer-inner { flex-direction: column; }
  .footer-links { justify-content: flex-start; }
}

@media (max-width: 560px) {
  .hero-actions { flex-direction: row; flex-wrap: nowrap; gap: 8px; }
  .hero-actions .button { width: auto; min-width: 0; flex: 1 1 0; padding-inline: 10px; font-size: 14px; gap: 6px; white-space: nowrap; }
  .hero-actions .os-mark { min-width: 26px; padding-inline: 4px; }
  .hero-meta { align-items: flex-start; }
  .hero-meta .status-dot { margin-top: .65em; }
  .product-window { border-radius: 12px; transform: none; }
  .reply-note { width: 92%; margin-top: 12px; }
  #features { padding-block: 36px; }
  #features .section-heading { margin-bottom: 18px; }
  #features .section-heading h2 { font-size: 1.8rem; }
  #features .section-heading p { margin-top: 10px; font-size: 15px; line-height: 1.6; }
  #features .feature-row { grid-template-columns: 40px minmax(0, 1fr); gap: 5px 12px; padding-block: 14px; }
  #features .feature-number { padding-top: 2px; font-size: 12px; }
  #features .feature-row h3 { font-size: 18px; }
  #features .feature-row p { grid-column: 2; font-size: 14px; line-height: 1.55; }
  .steps { grid-template-columns: 1fr; }
  .step + .step { border-left: 0; border-top: 1px solid #dfe4ec; }
  .section { padding-block: 64px; }
  .section-heading { margin-bottom: 34px; }
  .how-section { padding-block: 40px; }
  .how-section .section-heading { margin-bottom: 22px; }
  .how-section .section-heading h2 { font-size: 1.85rem; }
  .how-section .section-heading p { margin-top: 10px; font-size: 15px; line-height: 1.6; }
  .how-section .step {
    padding: 16px 0;
    display: grid;
    grid-template-columns: 28px minmax(0, 1fr);
    gap: 4px 12px;
  }
  .how-section .step-number {
    width: 28px;
    height: 28px;
    grid-row: 1 / 3;
    font-size: 12px;
  }
  .how-section .step h3 { margin: 1px 0 0; font-size: 17px; }
  .how-section .step p { grid-column: 2; font-size: 13px; line-height: 1.55; }
  .how-section .section-action { margin-top: 20px; }
  .page-hero { padding-block: 52px 42px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}