:root {
  color-scheme: dark;
  --bg: #0d1117;
  --bg-soft: #121826;
  --bg-panel: rgba(17, 22, 32, 0.92);
  --bg-panel-alt: rgba(20, 27, 39, 0.84);
  --line: rgba(255, 210, 112, 0.14);
  --line-soft: rgba(255, 255, 255, 0.08);
  --text: #f2f4f8;
  --muted: #aab2c0;
  --gold: #d8b25a;
  --gold-soft: rgba(216, 178, 90, 0.18);
  --gold-strong: #efcb72;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.48);
  --radius-xl: 28px;
  --radius-lg: 22px;
  --radius-md: 16px;
  --radius-sm: 12px;
  --max: 1200px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background:
    radial-gradient(circle at top left, rgba(216, 178, 90, 0.12), transparent 26%),
    radial-gradient(circle at 90% 15%, rgba(67, 92, 138, 0.2), transparent 22%),
    linear-gradient(180deg, #0b0f16 0%, #101621 45%, #0d1117 100%);
  color: var(--text);
  min-height: 100vh;
}

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

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

p {
  margin: 0;
  color: var(--muted);
  line-height: 1.7;
}

h1,
h2,
h3,
strong {
  margin: 0;
  color: var(--text);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.page-shell {
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 20px 20px 28px;
}

.site-header {
  position: sticky;
  top: 12px;
  z-index: 30;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 18px;
  margin-bottom: 24px;
  padding: 14px 18px;
  border: 1px solid var(--line-soft);
  border-radius: 22px;
  background: rgba(11, 15, 22, 0.75);
  backdrop-filter: blur(18px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.22);
}

.brand-row {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-mark img {
  width: 170px;
  height: auto;
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}

.site-nav a {
  padding: 10px 14px;
  border-radius: 999px;
  color: var(--muted);
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  background: rgba(216, 178, 90, 0.1);
  color: var(--text);
  transform: translateY(-1px);
}

.menu-button {
  display: none;
  width: 48px;
  height: 48px;
  padding: 0;
  border: 1px solid var(--line-soft);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.03);
  cursor: pointer;
}

.menu-button span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px auto;
  border-radius: 999px;
  background: var(--text);
}

.header-cta,
.footer-link,
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border-radius: 999px;
  font-weight: 700;
  letter-spacing: 0.01em;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.header-cta,
.btn-primary {
  color: #1b1407;
  background: linear-gradient(135deg, var(--gold-strong), #c49531);
  box-shadow: 0 12px 26px rgba(216, 178, 90, 0.3);
}

.header-cta:hover,
.btn-primary:hover,
.footer-link:hover {
  transform: translateY(-1px);
}

.btn-secondary {
  border: 1px solid rgba(216, 178, 90, 0.3);
  background: rgba(255, 255, 255, 0.04);
}

.btn-tertiary {
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.03);
}

.btn-wide {
  width: 100%;
}

.hero,
.split-section,
.install-section {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 22px;
  margin-bottom: 24px;
}

.hero {
  align-items: center;
  padding: 24px 0 10px;
}

.hero-copy {
  padding: 18px 0;
}

.eyebrow,
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid rgba(216, 178, 90, 0.22);
  border-radius: 999px;
  background: rgba(216, 178, 90, 0.08);
  color: var(--gold-strong);
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.hero h1 {
  margin-top: 18px;
  font-size: clamp(2.6rem, 5vw, 5rem);
  line-height: 0.95;
  letter-spacing: -0.04em;
}

.hero-lead {
  max-width: 62ch;
  margin-top: 18px;
  font-size: 1.05rem;
}

.hero-pills,
.hero-actions,
.hero-notes {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-pills {
  margin-top: 18px;
}

.hero-pills span {
  padding: 8px 12px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
  color: #dfe5f0;
}

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

.hero-notes {
  margin-top: 20px;
  padding-left: 18px;
  color: var(--muted);
}

.hero-notes li {
  margin: 0 0 6px;
}

.card-surface,
.section-surface,
.platform-card,
.compatibility-card,
.faq-item {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-xl);
  background: var(--bg-panel);
  box-shadow: var(--shadow);
}

.hero-visual {
  padding: 20px;
  overflow: hidden;
}

.hero-visual-top,
.hero-visual-bottom {
  display: flex;
  justify-content: space-between;
  gap: 14px;
}

.hero-visual-top {
  margin-bottom: 14px;
}

.status-chip {
  display: inline-flex;
  align-items: center;
  padding: 8px 11px;
  border-radius: 999px;
  background: rgba(216, 178, 90, 0.12);
  color: #f3d899;
  font-size: 0.86rem;
  font-weight: 700;
}

.status-chip--ghost {
  background: rgba(255, 255, 255, 0.05);
  color: #ced6e2;
}

.hero-image {
  width: 100%;
  margin: 4px 0 14px;
  border-radius: 22px;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.hero-visual-bottom > div {
  flex: 1;
  padding: 14px 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.04);
}

.hero-visual-bottom p {
  margin-top: 6px;
  font-size: 0.95rem;
}

.section-surface {
  padding: 24px;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 20px;
}

.section-head--compact {
  align-items: start;
}

.section-head h2 {
  margin-top: 12px;
  font-size: clamp(1.7rem, 2.4vw, 2.45rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
}

.section-head p {
  max-width: 44ch;
}

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

.platform-card {
  position: relative;
  padding: 22px;
  overflow: hidden;
}

.platform-card::after {
  content: "";
  position: absolute;
  inset: auto -40px -40px auto;
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(216, 178, 90, 0.16), transparent 72%);
  pointer-events: none;
}

.platform-card--mobile {
  background: linear-gradient(180deg, rgba(19, 25, 38, 0.96), rgba(12, 16, 23, 0.96));
}

.platform-card--desktop {
  background: linear-gradient(180deg, rgba(17, 23, 34, 0.96), rgba(12, 16, 23, 0.96));
}

.platform-card__icon {
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.05);
  margin-bottom: 14px;
}

.platform-card__icon img {
  width: 34px;
  height: 34px;
}

.platform-card h3,
.compatibility-card h3,
.install-step h3,
.faq-trigger span:first-child {
  font-size: 1.12rem;
}

.platform-card__meta {
  margin-top: 8px;
  color: #f0cf81;
  font-weight: 700;
}

.platform-card p {
  margin-top: 10px;
}

.platform-card .btn {
  margin-top: 18px;
}

.split-section {
  align-items: stretch;
}

.split-section__media {
  padding: 24px;
  overflow: hidden;
}

.card-surface--image {
  background: linear-gradient(180deg, rgba(17, 22, 32, 0.96), rgba(14, 18, 26, 0.96));
}

.card-surface--accent {
  background:
    linear-gradient(180deg, rgba(24, 29, 41, 0.96), rgba(16, 19, 28, 0.96)),
    radial-gradient(circle at top right, rgba(216, 178, 90, 0.08), transparent 40%);
}

.split-section__media h2 {
  margin-top: 12px;
  font-size: clamp(1.55rem, 2vw, 2.1rem);
  letter-spacing: -0.03em;
}

.split-section__media img {
  width: 100%;
  margin: 16px 0 12px;
  border-radius: 18px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.02);
}

.compatibility-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.compatibility-card {
  padding: 22px;
  background: linear-gradient(180deg, rgba(18, 24, 35, 0.94), rgba(13, 17, 25, 0.96));
}

.compatibility-card img {
  width: 54px;
  height: 54px;
  margin-bottom: 14px;
}

.compatibility-card p {
  margin-top: 10px;
}

.install-section {
  align-items: stretch;
}

.install-panel,
.install-aside {
  min-height: 100%;
}

.install-panel {
  padding: 24px;
}

.install-steps {
  display: grid;
  gap: 14px;
  margin-top: 16px;
}

.install-step {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 18px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.04);
}

.step-index {
  display: inline-grid;
  place-items: center;
  width: 58px;
  height: 58px;
  border-radius: 18px;
  background: linear-gradient(135deg, rgba(216, 178, 90, 0.18), rgba(255, 255, 255, 0.04));
  color: #f2d998;
  font-weight: 800;
}

.install-step p {
  margin-top: 6px;
}

.install-aside {
  position: relative;
  overflow: hidden;
  background-size: cover;
  background-position: center;
  border: 1px solid rgba(216, 178, 90, 0.18);
}

.install-aside__overlay {
  display: grid;
  align-content: end;
  min-height: 100%;
  padding: 28px;
  background: linear-gradient(180deg, rgba(9, 12, 18, 0.15), rgba(9, 12, 18, 0.88));
}

.install-aside h2 {
  margin-top: 12px;
  font-size: clamp(1.6rem, 2.4vw, 2.4rem);
  line-height: 1.05;
}

.install-aside p {
  margin: 12px 0 18px;
  max-width: 30ch;
  color: #d9dee8;
}

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

.faq-item {
  overflow: hidden;
  background: linear-gradient(180deg, rgba(18, 24, 35, 0.94), rgba(13, 17, 25, 0.96));
}

.faq-trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 20px 22px;
  border: 0;
  background: transparent;
  color: var(--text);
  text-align: left;
  cursor: pointer;
}

.faq-trigger span:first-child {
  line-height: 1.35;
}

.faq-icon {
  flex: none;
  position: relative;
  width: 18px;
  height: 18px;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background: #f0cf81;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.faq-icon::after {
  transform: rotate(90deg);
}

.faq-item.is-open .faq-icon::after {
  opacity: 0;
}

.faq-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.25s ease;
}

.faq-panel p {
  padding: 0 22px 20px;
}

.faq-item.is-open .faq-panel {
  max-height: 180px;
}

.final-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin: 24px 0 10px;
  padding: 24px;
}

.card-surface--final {
  background:
    radial-gradient(circle at top left, rgba(216, 178, 90, 0.14), transparent 26%),
    linear-gradient(135deg, rgba(15, 19, 28, 0.98), rgba(20, 26, 38, 0.98));
}

.final-cta h2 {
  margin-top: 12px;
  font-size: clamp(1.7rem, 2.5vw, 2.45rem);
  letter-spacing: -0.03em;
}

.final-cta p {
  margin-top: 10px;
}

.final-cta__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 12px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 4px 6px;
}

.footer-link {
  border: 1px solid rgba(216, 178, 90, 0.24);
}

@media (max-width: 1024px) {
  .site-header {
    grid-template-columns: 1fr;
  }

  .site-nav {
    justify-content: flex-start;
  }

  .hero,
  .split-section,
  .install-section {
    grid-template-columns: 1fr;
  }

  .platform-grid,
  .compatibility-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 720px) {
  .page-shell {
    padding: 14px 14px 20px;
  }

  .site-header {
    top: 0;
    border-radius: 0 0 20px 20px;
    margin: 0 -14px 16px;
    padding: 12px 14px 14px;
  }

  .brand-row {
    justify-content: space-between;
  }

  .menu-button {
    display: inline-block;
  }

  .site-nav {
    display: none;
    width: 100%;
    padding-top: 8px;
  }

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

  .header-cta {
    width: 100%;
  }

  .hero {
    padding-top: 10px;
  }

  .hero h1 {
    font-size: clamp(2.2rem, 12vw, 3.4rem);
  }

  .hero-actions,
  .final-cta__actions {
    flex-direction: column;
    align-items: stretch;
  }

  .platform-grid,
  .compatibility-grid {
    grid-template-columns: 1fr;
  }

  .section-head,
  .final-cta,
  .site-footer,
  .hero-visual-top,
  .hero-visual-bottom {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-visual-bottom > div {
    width: 100%;
  }

  .faq-trigger {
    padding: 18px 18px;
  }

  .faq-panel p {
    padding: 0 18px 18px;
  }

  .final-cta {
    align-items: stretch;
  }
}