:root {
  --sea: #88B4B7;
  --aqua: #B9D5D9;
  --crystal: #F0F5F9;
  --ash: #D7DCD9;
  --slate: #879796;
  --ink: #21363f;
  --muted: #5e7278;
  --line: rgba(135, 151, 150, 0.28);
  --surface: #ffffff;
  --shadow: 0 18px 45px rgba(38, 65, 72, 0.12);
  --soft-shadow: 0 8px 24px rgba(38, 65, 72, 0.08);
  --serif: Georgia, "Times New Roman", serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 10% 0%, rgba(185, 213, 217, 0.28), transparent 30rem),
    linear-gradient(180deg, #ffffff 0%, var(--crystal) 100%);
  font-family: var(--sans);
  line-height: 1.65;
}

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

a {
  color: #376f78;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: #234d55;
}

:focus-visible {
  outline: 3px solid var(--sea);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: 1rem;
  z-index: 20;
  transform: translateY(-140%);
  border-radius: 6px;
  background: var(--ink);
  color: #fff;
  padding: 0.65rem 0.85rem;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-shell {
  width: min(1500px, calc(100% - 2rem));
  margin: 2rem auto;
  overflow: clip;
  border: 1px solid rgba(135, 151, 150, 0.22);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--shadow);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 86px;
  padding: 0 2.8rem;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: #5b9298;
  font-family: var(--serif);
  font-size: clamp(2rem, 3vw, 3rem);
  font-weight: 700;
  letter-spacing: 0;
  text-decoration: none;
}

.brand-mark {
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.8vw, 3rem);
  font-size: 0.98rem;
  font-weight: 650;
}

.site-nav a {
  color: var(--ink);
  text-decoration: none;
}

.site-nav a[aria-current="page"] {
  color: #4d8790;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--ink);
}

.nav-toggle span,
.nav-toggle::before,
.nav-toggle::after {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px auto;
  content: "";
  background: currentColor;
}

main {
  min-height: 65vh;
}

.section {
  padding: clamp(2.5rem, 5vw, 5rem) clamp(1.2rem, 5vw, 5rem);
}

.section + .section {
  padding-top: 0;
}

.section-header {
  max-width: 760px;
  margin: 0 auto clamp(1.8rem, 4vw, 3rem);
  text-align: center;
}

.section-label,
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-height: 32px;
  margin-bottom: 0.8rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(240, 245, 249, 0.82);
  color: #4e7d84;
  padding: 0.28rem 0.7rem;
  font-size: 0.86rem;
  font-weight: 700;
}

h1,
h2,
h3,
h4 {
  color: #456f76;
  font-family: var(--serif);
  line-height: 1.08;
  letter-spacing: 0;
}

h1 {
  margin: 0 0 1rem;
  font-size: clamp(2.4rem, 7vw, 5.2rem);
}

h2 {
  margin: 0 0 1rem;
  font-size: clamp(2rem, 4.5vw, 3.2rem);
}

h3 {
  margin: 1.6rem 0 0.65rem;
  font-size: clamp(1.35rem, 2.6vw, 2rem);
}

h4 {
  margin: 1.2rem 0 0.35rem;
  font-size: 1.12rem;
}

.hero {
  position: relative;
  min-height: clamp(460px, 58vw, 690px);
  display: grid;
  align-items: center;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.hero img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero::after {
  position: absolute;
  inset: 0;
  content: "";
  background: linear-gradient(90deg, rgba(240, 245, 249, 0.88) 0%, rgba(240, 245, 249, 0.72) 34%, rgba(240, 245, 249, 0.12) 63%);
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 590px;
  margin-left: clamp(1.4rem, 8vw, 8rem);
  padding: 2rem 0;
}

.hero-content p {
  max-width: 480px;
  margin: 0 0 1.8rem;
  color: #2e454d;
  font-size: clamp(1rem, 1.6vw, 1.28rem);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
}

.button,
.button-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  border-radius: 6px;
  padding: 0.7rem 1.2rem;
  font-weight: 750;
  text-decoration: none;
}

.button {
  border: 1px solid #679ca2;
  background: linear-gradient(135deg, #6ba7ad, #5a9298);
  color: #fff;
}

.button:hover {
  color: #fff;
  background: #4f848a;
}

.button-secondary {
  border: 1px solid #82aeb3;
  background: rgba(255, 255, 255, 0.72);
  color: #32636b;
}

.feature-band {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  background: linear-gradient(90deg, rgba(185, 213, 217, 0.72), rgba(240, 245, 249, 0.88));
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.feature-band > div {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.9rem;
  align-items: center;
  min-height: 96px;
  padding: 1.2rem clamp(1.1rem, 4vw, 4.5rem);
  border-right: 1px solid rgba(135, 151, 150, 0.38);
}

.feature-band > div:last-child {
  border-right: 0;
}

.feature-band svg {
  width: 42px;
  height: 42px;
  color: #4f8790;
}

.feature-band strong {
  display: block;
  color: #31555d;
}

.feature-band span {
  display: block;
  color: #4f6268;
  font-size: 0.92rem;
  line-height: 1.35;
}

.grid {
  display: grid;
  gap: clamp(1rem, 2vw, 2rem);
}

.product-grid {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.product-index-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(1.4rem, 3vw, 2.4rem);
}

.home-products-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(1.4rem, 3vw, 2.4rem);
}

.article-grid {
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
}

.article-index-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.2rem, 2.4vw, 2rem);
}

.home-articles-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.2rem, 2.4vw, 2rem);
}

.card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: var(--soft-shadow);
}

.card-media {
  display: grid;
  place-items: center;
  aspect-ratio: 1.45 / 1;
  background: linear-gradient(145deg, #fff, var(--crystal));
  overflow: hidden;
}

.card-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.product-card .card-media img {
  object-fit: contain;
  padding: 1rem;
}

.card-body {
  display: flex;
  flex: 1;
  flex-direction: column;
  padding: 1.2rem;
}

.card h3 {
  margin: 0 0 0.55rem;
  color: #2f4e56;
  font-family: var(--sans);
  font-size: 1.08rem;
  line-height: 1.3;
}

.card p {
  margin: 0 0 1rem;
  color: #415960;
  font-size: 0.96rem;
  line-height: 1.48;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: auto;
  color: #4f8790;
  font-size: 0.92rem;
  font-weight: 750;
  text-decoration: none;
}

.split-index {
  display: grid;
  gap: 2.5rem;
}

.index-group h2 {
  margin-bottom: 1.35rem;
}

.page-hero {
  padding: clamp(2.8rem, 6vw, 5rem) clamp(1.2rem, 7vw, 7rem);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(240, 245, 249, 0.98), rgba(240, 245, 249, 0.55)),
    var(--hero-image, none) center / cover;
}

.page-hero-inner {
  max-width: 920px;
}

.page-hero p {
  max-width: 760px;
  color: #3d535a;
  font-size: clamp(1rem, 1.7vw, 1.2rem);
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  padding: 1.1rem clamp(1.2rem, 4vw, 4rem) 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.breadcrumbs a {
  color: #4e7d84;
  text-decoration: none;
}

.breadcrumbs span:not(:last-child)::after,
.breadcrumbs a::after {
  content: "/";
  margin-left: 0.45rem;
  color: var(--slate);
}

.product-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  padding: clamp(1.4rem, 4vw, 4rem);
}

.gallery-main-wrap {
  display: grid;
  place-items: center;
  overflow: hidden;
  aspect-ratio: 1 / 0.82;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(145deg, #fff, var(--crystal));
}

.gallery-main-wrap button {
  width: 100%;
  height: 100%;
  border: 0;
  background: transparent;
  cursor: zoom-in;
}

.gallery-main-wrap img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  padding: 1.5rem;
}

.thumbs {
  display: flex;
  gap: 0.8rem;
  margin-top: 1rem;
  overflow-x: auto;
  padding-bottom: 0.2rem;
}

.thumbs button {
  width: 88px;
  height: 88px;
  flex: 0 0 auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  padding: 0.25rem;
  cursor: pointer;
}

.thumbs button[aria-current="true"] {
  border-color: #5d969d;
  box-shadow: 0 0 0 2px rgba(136, 180, 183, 0.28);
}

.thumbs img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.product-summary h1 {
  font-size: clamp(2.1rem, 4.2vw, 4rem);
}

.product-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin: 1.1rem 0;
}

.pill {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(240, 245, 249, 0.78);
  padding: 0.35rem 0.7rem;
  color: #38565f;
  font-size: 0.9rem;
  font-weight: 700;
}

.compat-card,
.info-card,
.faq-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
  padding: clamp(1.2rem, 2vw, 1.7rem);
  box-shadow: var(--soft-shadow);
}

.compat-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: 0.7rem 1rem;
  padding: 0;
  margin: 1rem 0 0;
  list-style: none;
}

.compat-list li::before {
  content: "✓";
  display: inline-grid;
  place-items: center;
  width: 1.1rem;
  height: 1.1rem;
  margin-right: 0.45rem;
  border: 1px solid var(--sea);
  border-radius: 50%;
  color: #4f8790;
  font-size: 0.7rem;
}

.detail-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.4rem;
  padding: 0 clamp(1.2rem, 4vw, 4rem) clamp(2.5rem, 5vw, 5rem);
}

.info-card dl {
  display: grid;
  grid-template-columns: minmax(110px, 0.55fr) 1fr;
  gap: 0.7rem 1.1rem;
  margin: 0;
}

.info-card dt {
  font-weight: 800;
}

.info-card dd {
  margin: 0;
}

.content-layout {
  display: grid;
  grid-template-columns: 285px minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  padding: clamp(1.4rem, 4vw, 4rem);
}

.toc {
  position: sticky;
  top: 112px;
  align-self: start;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.86);
  padding: 1.1rem;
  box-shadow: var(--soft-shadow);
}

.toc h2 {
  margin: 0 0 0.9rem;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1rem;
}

.toc ol {
  display: grid;
  gap: 0.7rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.toc a {
  color: #405a61;
  font-size: 0.92rem;
  text-decoration: none;
}

.prose {
  max-width: 900px;
}

.prose > :first-child {
  margin-top: 0;
}

.prose p,
.prose li {
  color: #2f454d;
}

.prose ul,
.prose ol {
  padding-left: 1.35rem;
}

.prose li + li {
  margin-top: 0.35rem;
}

.prose img {
  border-radius: 8px;
  box-shadow: var(--soft-shadow);
}

.quick-answer,
.model-notice,
.important-notes,
.pdf-reminder,
.callout {
  margin: 1.3rem 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(135deg, rgba(185, 213, 217, 0.48), rgba(240, 245, 249, 0.9));
  padding: 1.1rem 1.25rem;
}

.article-image {
  margin: 1.6rem 0;
}

.article-image img,
.instruction-figure img {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.article-image figcaption,
.instruction-figure figcaption {
  margin-top: 0.5rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.service-page {
  max-width: 900px;
  margin: 0 auto;
  padding: clamp(2rem, 5vw, 5rem) clamp(1.2rem, 4vw, 4rem);
}

.faq-list {
  display: grid;
  gap: 0.75rem;
}

details {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

summary {
  cursor: pointer;
  padding: 1rem 1.1rem;
  color: var(--ink);
  font-weight: 800;
}

details > div {
  padding: 0 1.1rem 1rem;
}

.instruction-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 0.85rem;
  margin: 1.2rem 0;
}

.instruction-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  border: 1px solid #82aeb3;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.72);
  color: #32636b;
  padding: 0.7rem 1.2rem;
  font: inherit;
  font-weight: 750;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

.instruction-link:hover {
  color: #234d55;
  background: #fff;
}

.instruction-link-pdf {
  border-color: #679ca2;
  background: linear-gradient(135deg, #6ba7ad, #5a9298);
  color: #fff;
}

.instruction-link-pdf:hover {
  color: #fff;
  background: #4f848a;
}

.instruction-figure button {
  width: 100%;
  border: 0;
  background: transparent;
  padding: 0;
  cursor: zoom-in;
}

.dialog {
  width: min(96vw, 1300px);
  max-height: 94vh;
  border: 0;
  border-radius: 8px;
  background: #fff;
  padding: 3.2rem 1rem 1rem;
}

.dialog::backdrop {
  background: rgba(15, 26, 30, 0.78);
}

.dialog img {
  display: block;
  max-width: 100%;
  max-height: calc(94vh - 5rem);
  margin: auto;
  object-fit: contain;
}

.dialog button {
  position: absolute;
  top: 0.7rem;
  right: 0.7rem;
  width: 36px;
  height: 36px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: #fff;
  color: var(--ink);
  font-size: 1.3rem;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, #fff, var(--crystal));
}

.footer-main {
  display: grid;
  grid-template-columns: 1.2fr repeat(4, 1fr);
  gap: clamp(1.4rem, 3vw, 3rem);
  padding: clamp(2rem, 5vw, 4rem);
}

.footer-main h2,
.footer-main h3 {
  margin: 0 0 0.75rem;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 0.95rem;
}

.footer-main ul {
  display: grid;
  gap: 0.38rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-main a {
  color: #4a6269;
  font-size: 0.9rem;
  text-decoration: none;
}

.footer-brand p,
.affiliate-note {
  color: #596d73;
  font-size: 0.92rem;
}

.footer-bottom {
  padding: 1rem clamp(1.2rem, 5vw, 4rem);
  border-top: 1px solid var(--line);
  color: #64777d;
  font-size: 0.86rem;
}

@media (max-width: 980px) {
  .site-shell {
    width: min(100% - 1rem, 1500px);
    margin: 0.5rem auto;
  }

  .site-header {
    min-height: 72px;
    padding: 0 1rem;
  }

  .brand {
    font-size: 2rem;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border-bottom: 1px solid var(--line);
    background: #fff;
  }

  .site-nav[data-open] {
    display: flex;
  }

  .site-nav a {
    padding: 1rem 1.25rem;
    border-top: 1px solid var(--line);
  }

  .hero {
    min-height: 520px;
  }

  .hero img {
    object-position: 63% center;
  }

  .hero::after {
    background: linear-gradient(90deg, rgba(240, 245, 249, 0.94) 0%, rgba(240, 245, 249, 0.78) 54%, rgba(240, 245, 249, 0.18) 100%);
  }

  .hero-content {
    margin-left: 1.25rem;
    max-width: 520px;
  }

  .product-layout,
  .content-layout,
  .detail-grid {
    grid-template-columns: 1fr;
  }

  .toc {
    position: static;
  }

  .footer-main {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .article-index-grid,
  .home-articles-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .product-index-grid,
  .home-products-grid,
  .article-index-grid,
  .home-articles-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .site-shell {
    width: 100%;
    margin: 0;
    border-left: 0;
    border-right: 0;
    border-radius: 0;
  }

  .section,
  .page-hero,
  .product-layout,
  .content-layout,
  .detail-grid {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  h1 {
    font-size: 2.45rem;
  }

  .hero {
    min-height: 560px;
    align-items: start;
  }

  .hero::after {
    background: linear-gradient(180deg, rgba(240, 245, 249, 0.96) 0%, rgba(240, 245, 249, 0.72) 44%, rgba(240, 245, 249, 0.08) 100%);
  }

  .hero-content {
    margin: 0;
    padding: 2rem 1rem;
  }

  .button-row,
  .instruction-actions {
    display: grid;
  }

  .button,
  .button-secondary {
    width: 100%;
  }

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

  .feature-band > div {
    border-right: 0;
    border-bottom: 1px solid rgba(135, 151, 150, 0.38);
  }

  .feature-band > div:last-child {
    border-bottom: 0;
  }

  .footer-main {
    grid-template-columns: 1fr;
  }

  .info-card dl {
    grid-template-columns: 1fr;
  }
}