:root {
  color-scheme: light dark;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --page: #f4f7fb;
  --surface: #ffffff;
  --surface-strong: #f9fbff;
  --text: #132238;
  --muted: #5f6f83;
  --line: #dce4ef;
  --accent: #278bd7;
  --accent-deep: #1266ad;
  --accent-soft: #e8f4ff;
  --purple: #7559e8;
  --purple-soft: #f0edff;
  --shadow: 0 24px 70px rgba(24, 55, 87, .11);
  background: var(--page);
  color: var(--text);
}

* { box-sizing: border-box; }
html { min-height: 100%; scroll-behavior: smooth; }
body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 8% -8%, rgba(39, 139, 215, .18), transparent 34rem),
    radial-gradient(circle at 96% 10%, rgba(117, 89, 232, .12), transparent 30rem),
    var(--page);
}
a { color: inherit; }
.shell { width: min(1120px, calc(100% - 32px)); margin-inline: auto; }
.skip-link {
  position: fixed;
  inset-block-start: 10px;
  inset-inline-start: 10px;
  z-index: 20;
  padding: 10px 14px;
  border-radius: 10px;
  color: #fff;
  background: var(--accent-deep);
  transform: translateY(-150%);
}
.skip-link:focus { transform: none; }

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 10;
  border-block-end: 1px solid color-mix(in srgb, var(--line) 78%, transparent);
  background: color-mix(in srgb, var(--page) 86%, transparent);
  backdrop-filter: blur(18px);
}
.header-shell { display: grid; }
.nav {
  display: flex;
  min-height: 72px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  color: inherit;
  text-decoration: none;
}
.brand-mark, .footer-mark {
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(145deg, #54b4f3, var(--accent-deep));
  font-weight: 850;
  box-shadow: 0 10px 25px rgba(39, 139, 215, .22);
}
.brand-mark { width: 40px; height: 40px; border-radius: 14px; }
.brand-copy { display: grid; gap: 1px; }
.brand-copy strong { font-size: 15px; letter-spacing: .01em; }
.brand-copy small { color: var(--muted); font-size: 11px; }
.nav-actions { display: flex; align-items: center; gap: 5px; }
.nav-link {
  padding: 8px 10px;
  border-radius: 10px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}
.nav-link.active { color: var(--accent-deep); background: var(--accent-soft); }
.product-nav-row {
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  padding-block-end: 10px;
}
.product-nav {
  display: flex;
  flex: 1 1 auto;
  align-items: center;
  gap: 5px;
  min-width: 0;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scrollbar-width: none;
}
.product-nav::-webkit-scrollbar { display: none; }
.product-nav-link {
  flex: 0 0 auto;
  padding: 8px 11px;
  border-radius: 10px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 750;
  line-height: 1.2;
  text-decoration: none;
  white-space: nowrap;
}
.product-nav-link.active {
  color: var(--accent-deep);
  background: var(--accent-soft);
}
.product-nav-cta {
  flex: 0 0 auto;
  color: #fff;
  background: var(--accent-deep);
}

.main-content { padding-block: clamp(52px, 8vw, 104px) 72px; }
.hero { max-width: 860px; }
.eyebrow {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  margin-block-end: 18px;
  padding-inline: 11px;
  border: 1px solid color-mix(in srgb, var(--accent) 28%, transparent);
  border-radius: 999px;
  color: var(--accent-deep);
  background: color-mix(in srgb, var(--accent-soft) 78%, transparent);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .055em;
  text-transform: uppercase;
}
h1, h2, h3, p { margin-block-start: 0; }
h1 {
  max-width: 900px;
  margin-block-end: 20px;
  font-size: clamp(38px, 7vw, 76px);
  line-height: 1.02;
  letter-spacing: -.052em;
}
.detail-hero h1 { font-size: clamp(36px, 6vw, 66px); }
.lead {
  max-width: 760px;
  margin-block-end: 0;
  color: var(--muted);
  font-size: clamp(17px, 2.2vw, 21px);
  line-height: 1.65;
}
.tagline {
  margin-block-end: 14px;
  color: var(--accent-deep);
  font-size: clamp(19px, 2.4vw, 25px);
  font-weight: 800;
}
.included {
  display: flex;
  align-items: center;
  gap: 13px;
  max-width: 780px;
  margin-block: 34px 0;
  padding: 16px 18px;
  border: 1px solid color-mix(in srgb, var(--purple) 22%, var(--line));
  border-radius: 18px;
  background: color-mix(in srgb, var(--purple-soft) 68%, var(--surface));
  box-shadow: 0 12px 38px rgba(49, 35, 118, .06);
}
.included-icon { font-size: 24px; }
.included p { margin: 0; color: var(--text); font-weight: 720; line-height: 1.5; }

.catalog-section { margin-block-start: clamp(50px, 8vw, 84px); }
.section-heading { max-width: 660px; margin-block-end: 24px; }
.section-heading h2 { margin-block-end: 8px; font-size: clamp(25px, 4vw, 36px); letter-spacing: -.03em; }
.section-heading p { color: var(--muted); line-height: 1.55; }
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; }
.product-card {
  display: flex;
  min-height: 280px;
  flex-direction: column;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 26px;
  color: inherit;
  background: color-mix(in srgb, var(--surface) 94%, transparent);
  box-shadow: 0 14px 50px rgba(24, 55, 87, .07);
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.product-card:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--accent) 44%, var(--line));
  box-shadow: var(--shadow);
}
.product-icon {
  display: grid;
  width: 52px;
  height: 52px;
  place-items: center;
  margin-block-end: 28px;
  border-radius: 17px;
  background: var(--accent-soft);
  font-size: 25px;
}
.product-card:nth-child(2) .product-icon { background: var(--purple-soft); }
.product-card:nth-child(3) .product-icon { background: #fff2df; }
.product-card:nth-child(4) .product-icon { background: #e9f9ef; }
.product-card h2 { margin-block-end: 10px; font-size: 22px; letter-spacing: -.025em; }
.product-card p { margin-block-end: 25px; color: var(--muted); line-height: 1.55; }
.card-link { margin-block-start: auto; color: var(--accent-deep); font-size: 14px; font-weight: 800; }

.breadcrumb {
  display: inline-flex;
  margin-block-end: 26px;
  color: var(--accent-deep);
  font-size: 14px;
  font-weight: 750;
  text-decoration: none;
}
.detail-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 360px);
  gap: 22px;
  align-items: start;
  margin-block-start: clamp(44px, 7vw, 76px);
}
.details-list { display: grid; gap: 12px; }
.details-list details {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: color-mix(in srgb, var(--surface) 96%, transparent);
  box-shadow: 0 10px 34px rgba(24, 55, 87, .055);
}
.details-list summary {
  display: flex;
  min-height: 62px;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 17px 19px;
  cursor: pointer;
  font-weight: 790;
  list-style: none;
}
.details-list summary::-webkit-details-marker { display: none; }
.details-list summary::after {
  content: "+";
  display: grid;
  flex: 0 0 auto;
  width: 25px;
  height: 25px;
  place-items: center;
  border-radius: 9px;
  color: var(--accent-deep);
  background: var(--accent-soft);
}
.details-list details[open] summary::after { content: "−"; }
.details-list details p {
  margin: 0;
  padding: 0 19px 19px;
  color: var(--muted);
  line-height: 1.62;
}
.side-stack { display: grid; gap: 14px; }
.side-card {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--surface);
  box-shadow: 0 16px 48px rgba(24, 55, 87, .075);
}
.side-card.example { background: linear-gradient(145deg, var(--purple-soft), var(--surface)); }
.side-card h2 { margin-block-end: 8px; font-size: 19px; }
.side-card p { margin-block-end: 18px; color: var(--muted); line-height: 1.55; }
.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 10px 16px;
  border-radius: 13px;
  color: #fff;
  background: linear-gradient(145deg, #3aa7ee, var(--accent-deep));
  font-size: 14px;
  font-weight: 800;
  text-align: center;
  text-decoration: none;
  box-shadow: 0 12px 28px rgba(39, 139, 215, .2);
}
.button.secondary { color: var(--accent-deep); background: var(--accent-soft); box-shadow: none; }
.button-row { display: flex; flex-wrap: wrap; gap: 9px; }
.button:focus-visible, .product-card:focus-visible, .nav-link:focus-visible, .product-nav-link:focus-visible, .brand:focus-visible, summary:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent) 42%, transparent);
  outline-offset: 3px;
}

.guide-hero { max-width: 920px; }
.guide-toc {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-block-start: 28px;
}
.guide-toc a {
  padding: 9px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--accent-deep);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  font-size: 13px;
  font-weight: 760;
  text-decoration: none;
}
.guide-section {
  scroll-margin-block-start: 88px;
  margin-block-start: clamp(52px, 8vw, 88px);
}
.guide-section-heading {
  max-width: 780px;
  margin-block-end: 24px;
}
.guide-section-heading h2 {
  margin-block-end: 9px;
  font-size: clamp(27px, 4vw, 39px);
  letter-spacing: -.035em;
}
.guide-section-heading p { margin: 0; color: var(--muted); font-size: 16px; line-height: 1.62; }
.step-grid,
.guide-item-grid,
.example-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 13px;
}
.step-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.guide-item,
.guide-step,
.guide-example {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: color-mix(in srgb, var(--surface) 95%, transparent);
  box-shadow: 0 12px 38px rgba(24, 55, 87, .055);
}
.guide-step { border-block-start: 3px solid var(--accent); }
.guide-item h3,
.guide-step h3,
.guide-example h3 { margin: 0 0 8px; font-size: 17px; letter-spacing: -.018em; }
.guide-item p,
.guide-step p,
.guide-example p { margin: 0; color: var(--muted); line-height: 1.62; }
.guide-example { background: linear-gradient(145deg, var(--purple-soft), var(--surface)); }
.guide-note {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  margin-block-start: 18px;
  padding: 20px;
  border: 1px solid color-mix(in srgb, var(--purple) 28%, var(--line));
  border-radius: 21px;
  background: color-mix(in srgb, var(--purple-soft) 72%, var(--surface));
}
.guide-note-icon { font-size: 25px; }
.guide-note h2 { margin: 0 0 6px; font-size: 18px; }
.guide-note p { margin: 0; color: var(--muted); line-height: 1.6; }
.guide-actions { margin-block-start: 28px; }
.rotation-guide-card { background: linear-gradient(145deg, var(--accent-soft), var(--surface)); }
.guide-toc a:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent) 42%, transparent);
  outline-offset: 3px;
}

.footer {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-block: 28px 42px;
  border-block-start: 1px solid var(--line);
  color: var(--muted);
}
.footer-mark { width: 30px; height: 30px; border-radius: 10px; font-size: 12px; }
.footer p { margin: 0; font-size: 13px; }

@media (max-width: 820px) {
  .card-grid { grid-template-columns: 1fr; }
  .product-card { min-height: 0; }
  .detail-layout { grid-template-columns: 1fr; }
  .side-stack { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .step-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 560px) {
  .shell { width: min(100% - 24px, 1120px); }
  .nav { min-height: 64px; gap: 12px; }
  .brand-copy small { display: none; }
  .nav-link { padding-inline: 7px; font-size: 12px; }
  .product-nav-row { align-items: flex-start; gap: 5px; }
  .product-nav { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); overflow-x: visible; }
  .product-nav-link { padding-inline: 9px; text-align: center; font-size: 12px; }
  .main-content { padding-block-start: 42px; }
  .side-stack { grid-template-columns: 1fr; }
  .included { align-items: flex-start; }
  .step-grid, .guide-item-grid, .example-grid { grid-template-columns: 1fr; }
  .guide-item, .guide-step, .guide-example { padding: 17px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .product-card { transition: none; }
}
@media (prefers-color-scheme: dark) {
  :root {
    --page: #0e1724;
    --surface: #152235;
    --surface-strong: #18273b;
    --text: #edf5ff;
    --muted: #a7b6c8;
    --line: #293b51;
    --accent: #4db4f5;
    --accent-deep: #76c8fa;
    --accent-soft: #17354d;
    --purple: #9b87ff;
    --purple-soft: #282345;
    --shadow: 0 24px 70px rgba(0, 0, 0, .32);
  }
  .button { color: #07121d; }
  .product-card:nth-child(3) .product-icon { background: #47361f; }
  .product-card:nth-child(4) .product-icon { background: #173b2a; }
}