:root {
  --bg: #241d6d;
  --bg-deep: #1a1452;
  --bg-soft: #2e2680;
  --bg-light: #f9f9f9;
  --bg-white: #ffffff;
  --text: #1e1a3a;
  --text-muted: #6b6785;
  --text-on-dark: #f4f2ff;
  --accent: #2ddbbd;
  --accent-hover: #4aebcf;
  --gold: #ffcc2f;
  --line: #ebe8f5;
  --radius: 12px;
  --max: 1140px;
  --header-h: 64px;
  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg-white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body.nav-open {
  overflow: hidden;
}

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

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

ul {
  list-style: none;
}

.container {
  width: 100%;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  height: var(--header-h);
  background: rgba(36, 29, 109, 0.88);
  backdrop-filter: blur(10px);
  transition: background 0.25s ease;
}

.site-header.is-solid {
  background: var(--bg);
}

.header-inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 18px;
}

.brand img {
  height: 28px;
  width: auto;
}

.brand small {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
  letter-spacing: 0.04em;
}

.nav-desktop {
  display: none;
  align-items: center;
  gap: 8px;
}

.nav-desktop a {
  color: rgba(255, 255, 255, 0.88);
  font-size: 15px;
  padding: 8px 10px;
  border-radius: 8px;
}

.nav-desktop a:hover,
.nav-desktop a.is-active {
  color: var(--gold);
}

.header-actions {
  display: none;
  align-items: center;
  gap: 10px;
}

.menu-btn {
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 10px;
  background: transparent;
  color: #fff;
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  cursor: pointer;
}

.menu-btn span {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
}

.mobile-menu {
  display: none;
  position: fixed;
  inset: var(--header-h) 0 0;
  z-index: 99;
  background: var(--bg-deep);
  padding: 24px 16px 40px;
  overflow: auto;
}

.mobile-menu.is-open {
  display: block;
}

.mobile-menu a {
  display: block;
  color: #fff;
  padding: 14px 4px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 16px;
}

.mobile-menu .btn {
  margin-top: 18px;
  width: 100%;
  text-align: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 10px 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform 0.2s ease, background 0.2s ease, color 0.2s ease;
  cursor: pointer;
}

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

.btn-primary {
  background: var(--accent);
  color: #0b3d36;
}

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

.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.35);
}

.btn-ghost:hover {
  background: #fff;
  color: var(--bg);
}

.btn-outline-dark {
  background: transparent;
  color: var(--text);
  border-color: #d8d4ea;
}

.hero {
  position: relative;
  min-height: 100vh;
  padding: calc(var(--header-h) + 48px) 0 72px;
  background:
    radial-gradient(ellipse 70% 55% at 80% 20%, rgba(45, 219, 189, 0.2), transparent 60%),
    linear-gradient(160deg, #1a1452 0%, #241d6d 45%, #2e2680 100%);
  color: var(--text-on-dark);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  gap: 40px;
  align-items: center;
}

.hero-eyebrow {
  color: var(--gold);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.hero h1 {
  font-size: clamp(32px, 6vw, 56px);
  line-height: 1.15;
  font-weight: 800;
  margin-bottom: 16px;
}

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

.hero .lead {
  font-size: 16px;
  line-height: 1.75;
  color: rgba(244, 242, 255, 0.82);
  max-width: 540px;
  margin-bottom: 28px;
}

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

.phone-stage {
  position: relative;
  width: min(280px, 70vw);
  margin: 0 auto;
}

.phone-frame {
  position: relative;
  border-radius: 36px;
  border: 10px solid #111;
  background: #111;
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.45);
  overflow: hidden;
}

.phone-frame img {
  width: 100%;
  height: auto;
}

.scroll-hint {
  position: absolute;
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.35);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 18px;
  animation: bob 1.6s ease-in-out infinite;
}

@keyframes bob {
  0%,
  100% {
    transform: translate(-50%, 0);
  }
  50% {
    transform: translate(-50%, 6px);
  }
}

.section {
  padding: 88px 0;
}

.section-muted {
  background: var(--bg-light);
}

.section-dark {
  background: var(--bg);
  color: var(--text-on-dark);
}

.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: clamp(26px, 4vw, 36px);
  margin-bottom: 10px;
}

.section-title p {
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto;
}

.section-dark .section-title p {
  color: rgba(244, 242, 255, 0.65);
}

.feature-grid {
  display: grid;
  gap: 20px;
}

.feature-card {
  background: var(--bg-white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  text-align: center;
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 32px rgba(36, 29, 109, 0.1);
}

.feature-icon {
  width: 52px;
  height: 52px;
  margin: 0 auto 16px;
  border-radius: 14px;
  background: rgba(45, 219, 189, 0.14);
  color: #0f8f79;
  display: grid;
  place-items: center;
}

.feature-icon svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.feature-card h3 {
  font-size: 20px;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
}

.split-row {
  display: grid;
  gap: 32px;
  align-items: center;
  margin-bottom: 56px;
}

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

.split-copy h2 {
  font-size: clamp(24px, 3.5vw, 32px);
  margin-bottom: 14px;
}

.split-copy p {
  color: var(--text-muted);
  margin-bottom: 22px;
  line-height: 1.75;
}

.split-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.split-visual img {
  width: 100%;
  height: auto;
  background: #eceaf5;
  border-radius: 18px;
  box-shadow: 0 18px 40px rgba(36, 29, 109, 0.12);
}

.about-grid {
  display: grid;
  gap: 28px;
  align-items: center;
}

.about-list {
  display: grid;
  gap: 18px;
}

.about-item {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 12px;
  align-items: start;
}

.about-item .icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(45, 219, 189, 0.14);
  color: #0f8f79;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 14px;
}

.about-item h4 {
  font-size: 17px;
  margin-bottom: 4px;
}

.about-item p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.65;
}

.about-device {
  width: min(260px, 70%);
  margin: 0 auto;
}

.about-device img {
  width: 100%;
  height: auto;
  border-radius: 28px;
  box-shadow: 0 24px 48px rgba(36, 29, 109, 0.16);
}

.showcase-grid {
  display: grid;
  gap: 20px;
  justify-items: center;
}

.showcase-grid img {
  width: min(100%, 240px);
  height: auto;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: #1a1452;
}

.security-grid {
  display: grid;
  gap: 18px;
}

.security-card {
  background: var(--bg-white);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  padding: 28px 22px;
}

.security-card h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.security-card p {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
}

.cert-block {
  display: grid;
  gap: 28px;
  align-items: center;
}

.cert-copy h2 {
  font-size: clamp(24px, 3.5vw, 32px);
  margin-bottom: 8px;
}

.cert-copy .tag {
  display: inline-block;
  color: var(--gold);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 14px;
}

.cert-copy p {
  color: rgba(244, 242, 255, 0.78);
  line-height: 1.75;
}

.cert-visual img {
  width: min(360px, 100%);
  height: auto;
  margin: 0 auto;
  border-radius: 16px;
}

.faq-layout {
  display: grid;
  gap: 32px;
  align-items: start;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-white);
  overflow: hidden;
}

.faq-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  text-align: left;
  background: transparent;
  border: 0;
  padding: 16px 18px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  color: var(--text);
}

.faq-trigger .num {
  display: inline-flex;
  width: 24px;
  height: 24px;
  margin-right: 8px;
  border-radius: 50%;
  background: rgba(45, 219, 189, 0.18);
  color: #0f8f79;
  align-items: center;
  justify-content: center;
  font-size: 12px;
}

.faq-body {
  display: none;
  padding: 0 18px 16px 50px;
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
}

.faq-item.is-open .faq-body {
  display: block;
}

.faq-side {
  width: min(240px, 70%);
  margin: 0 auto;
}

.faq-side img {
  width: 100%;
  height: auto;
  border-radius: 28px;
  box-shadow: 0 18px 40px rgba(36, 29, 109, 0.12);
}

.download-panel {
  text-align: center;
}

.download-panel h2 {
  font-size: clamp(26px, 4vw, 36px);
  margin-bottom: 12px;
}

.download-panel p {
  color: rgba(244, 242, 255, 0.75);
  max-width: 560px;
  margin: 0 auto 28px;
}

.download-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.site-footer {
  background: var(--bg-light);
  padding: 40px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
}

.site-footer .links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
  margin-bottom: 14px;
}

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

.fade-up {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.fade-up.is-visible {
  opacity: 1;
  transform: none;
}

.fade-up.delay-1 {
  transition-delay: 0.08s;
}

.fade-up.delay-2 {
  transition-delay: 0.16s;
}

@media (min-width: 768px) {
  .nav-desktop,
  .header-actions {
    display: flex;
  }

  .menu-btn {
    display: none;
  }

  .hero-grid {
    grid-template-columns: 1.15fr 0.85fr;
  }

  .feature-grid,
  .security-grid,
  .showcase-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .split-row {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .split-row.is-reverse .split-copy {
    order: 2;
  }

  .split-row.is-reverse .split-visual {
    order: 1;
  }

  .about-grid {
    grid-template-columns: 1fr 0.85fr 1fr;
  }

  .cert-block {
    grid-template-columns: 0.9fr 1.1fr;
  }

  .faq-layout {
    grid-template-columns: 1.3fr 0.7fr;
  }
}

@media (max-width: 767px) {
  .section {
    padding: 64px 0;
  }

  .hero {
    padding-top: calc(var(--header-h) + 28px);
  }

  .hero-actions .btn,
  .download-actions .btn {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .scroll-hint {
    animation: none;
  }

  .fade-up {
    opacity: 1;
    transform: none;
    transition: none;
  }
}


body.v-compact .about-grid { grid-template-columns: 1fr; max-width: 720px; margin: 0 auto; }
body.v-compact .about-device { order: -1; margin-bottom: 12px; }