:root {
  --color-primary: #0066cc;
  --color-primary-focus: #0071e3;
  --color-primary-on-dark: #2997ff;
  --color-ink: #1d1d1f;
  --color-body: #1d1d1f;
  --color-body-on-dark: #ffffff;
  --color-body-muted: #cccccc;
  --color-ink-muted-80: #333333;
  --color-ink-muted-48: #7a7a7a;
  --color-divider-soft: #f0f0f0;
  --color-hairline: #e0e0e0;
  --color-canvas: #ffffff;
  --color-canvas-parchment: #f5f5f7;
  --color-surface-pearl: #fafafc;
  --color-surface-tile-1: #272729;
  --color-surface-tile-2: #2a2a2c;
  --color-surface-tile-3: #252527;
  --color-surface-black: #000000;
  --color-on-primary: #ffffff;
  --font-display: "SF Pro Display", system-ui, -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  --font-text: "SF Pro Text", system-ui, -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  --type-hero-size: clamp(2.4rem, 6vw, 3.5rem);
  --type-display-lg: clamp(2rem, 4vw, 2.5rem);
  --type-display-md: clamp(1.6rem, 3vw, 2.125rem);
  --type-lead: clamp(1.15rem, 2.5vw, 1.75rem);
  --radius-none: 0;
  --radius-sm: 8px;
  --radius-md: 11px;
  --radius-lg: 18px;
  --radius-pill: 9999px;
  --spacing-section: clamp(64px, 9vw, 96px);
  --container-text: 980px;
  --container-wide: 1440px;
  --gutter: 24px;
  --product-shadow: rgba(0, 0, 0, 0.22) 3px 5px 30px 0;
  --image-hero: url("../assets/images/hero.webp");
  --image-elder: url("../assets/images/elder.webp");
  --image-family: url("../assets/images/family.webp");
  --image-school: url("../assets/images/school.webp");
  --image-school-phone: url("../assets/images/school-phone.webp");
  --image-office: url("../assets/images/office.webp");
  --image-remote-worker: url("../assets/images/silverarcs-work.webp");
  --image-asian-laptop: url("../assets/images/silverarcs-work.webp");
  --image-retro-phone: url("../assets/images/retro-phone.webp");
  --image-silverarcs: url("../assets/images/silverarcs-work.webp");
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--color-body); background: var(--color-canvas); font-family: var(--font-text); font-size: 17px; line-height: 1.47; letter-spacing: -0.374px; }
a { color: inherit; }
img { max-width: 100%; display: block; }
.site-header { position: sticky; top: 0; z-index: 10; }
.global-nav { min-height: 44px; background: var(--color-surface-black); color: var(--color-body-on-dark); display: flex; align-items: center; gap: 20px; padding: 0 24px; font-size: 12px; line-height: 1; letter-spacing: -0.12px; }
.brand, .footer-brand { display: inline-flex; align-items: center; gap: 8px; text-decoration: none; font-weight: 600; white-space: nowrap; }
.desktop-nav { flex: 1; display: flex; align-items: center; justify-content: center; gap: clamp(10px, 1.4vw, 20px); }
.desktop-nav a, .mobile-nav a { text-decoration: none; opacity: .9; }
.desktop-nav a[aria-current="page"], .mobile-nav a[aria-current="page"] { color: var(--color-primary-on-dark); }
.nav-cta { background: var(--color-primary); color: var(--color-on-primary); text-decoration: none; border-radius: var(--radius-pill); padding: 8px 15px; white-space: nowrap; }
.sub-nav { min-height: 52px; background: color-mix(in srgb, var(--color-canvas-parchment) 86%, transparent); backdrop-filter: blur(18px); color: var(--color-ink); display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 0 24px; border-bottom: 1px solid rgba(0,0,0,.06); }
.sub-nav a { text-decoration: none; font-size: 21px; font-weight: 600; }
.sub-nav span { font-size: 14px; color: var(--color-ink-muted-48); }
.mobile-nav { display: none; }
.mobile-nav summary { list-style: none; width: 44px; height: 44px; display: grid; place-content: center; gap: 5px; cursor: pointer; }
.mobile-nav summary::-webkit-details-marker { display: none; }
.mobile-nav summary span { width: 18px; height: 1px; background: #fff; display: block; }
.mobile-nav nav { position: absolute; left: 0; right: 0; top: 44px; background: var(--color-surface-black); display: grid; gap: 0; padding: 10px 24px 24px; border-top: 1px solid rgba(255,255,255,.12); }
.mobile-nav nav a { padding: 14px 0; border-bottom: 1px solid rgba(255,255,255,.12); }
.mobile-line { color: var(--color-primary-on-dark); }
.tile { padding: var(--spacing-section) max(24px, calc((100vw - var(--container-wide)) / 2)); }
.tile-light { background: var(--color-canvas); color: var(--color-ink); }
.tile-parchment { background: var(--color-canvas-parchment); color: var(--color-ink); }
.tile-dark { background: var(--color-surface-tile-1); color: var(--color-body-on-dark); }
.tile-dark .card { background: var(--color-surface-tile-2); color: var(--color-body-on-dark); border-color: rgba(255,255,255,.12); }
.hero { min-height: calc(100vh - 96px); display: grid; place-items: center; gap: 48px; grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.1fr); }
.hero-copy { max-width: 720px; text-align: center; justify-self: center; }
.hero h1, .page-title h1 { font-family: var(--font-display); font-size: var(--type-hero-size); line-height: 1.07; font-weight: 600; letter-spacing: -0.28px; margin: 0 0 18px; }
.hero-visual { width: min(720px, 100%); aspect-ratio: 16 / 10; overflow: hidden; background: var(--color-canvas-parchment); }
.photo, .photo-tile { width: 100%; height: 100%; background-position: center; background-size: cover; }
.photo-hero { background-image: var(--image-hero); }
.photo-elder { background-image: var(--image-elder); }
.photo-family { background-image: var(--image-family); }
.photo-school { background-image: var(--image-school); }
.photo-school-phone { background-image: var(--image-school-phone); }
.photo-office { background-image: var(--image-office); }
.photo-retro { background-image: var(--image-retro-phone); }
.photo-silverarcs { background-image: var(--image-silverarcs); }
.photo-tile { min-height: 520px; }
.product-shadow { box-shadow: var(--product-shadow); }
.eyebrow { color: var(--color-ink-muted-48); font-size: 14px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; margin: 0 0 12px; }
.eyebrow.on-dark { color: var(--color-body-muted); }
.lead { font-family: var(--font-display); font-size: var(--type-lead); line-height: 1.28; font-weight: 400; margin: 0 auto 28px; max-width: 850px; }
.lead.narrow { max-width: 760px; }
h2 { font-family: var(--font-display); font-size: var(--type-display-lg); line-height: 1.1; font-weight: 600; margin: 0 0 18px; letter-spacing: 0; }
h3 { font-size: 17px; line-height: 1.24; font-weight: 600; margin: 0 0 8px; }
p { margin: 0 0 1em; }
.center-block { max-width: var(--container-text); margin: 0 auto; text-align: center; }
.center-block p:not(.eyebrow) { font-size: clamp(1.1rem, 2.2vw, 1.5rem); line-height: 1.5; font-weight: 300; }
.section-head { max-width: var(--container-text); margin: 0 auto 40px; text-align: center; }
.section-head p { color: var(--color-ink-muted-48); }
.tile-dark .section-head p:not(.eyebrow), .tile-dark .center-block p:not(.eyebrow) { color: var(--color-body-muted); }
.button-row { display: flex; justify-content: center; align-items: center; gap: 12px; flex-wrap: wrap; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; border-radius: var(--radius-pill); padding: 11px 22px; text-decoration: none; font-size: 17px; line-height: 1; border: 1px solid transparent; transition: transform .18s ease; }
.button:active { transform: scale(.95); }
.button.primary { background: var(--color-primary); color: var(--color-on-primary); }
.button.secondary { background: var(--color-canvas); color: var(--color-primary); border-color: var(--color-primary); }
.button.secondary.on-dark { background: transparent; color: var(--color-primary-on-dark); border-color: var(--color-primary-on-dark); }
.text-link { color: var(--color-primary); text-decoration: none; }
.text-link:hover { text-decoration: underline; }
.card-grid { display: grid; gap: 24px; max-width: var(--container-wide); margin: 0 auto; }
.cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.cols-5 { grid-template-columns: repeat(5, minmax(0, 1fr)); }
.card { background: var(--color-canvas); border: 1px solid var(--color-hairline); border-radius: var(--radius-lg); padding: 24px; }
.card p:last-child { margin-bottom: 0; }
.price { color: var(--color-ink-muted-48); }
.price strong { font-family: var(--font-display); font-size: 2rem; color: var(--color-ink); letter-spacing: -.02em; }
.tile-dark .price strong { color: #fff; }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(320px, 0.85fr); gap: 56px; align-items: center; }
.split > div:first-child { max-width: 720px; justify-self: center; }
.check-list { list-style: none; padding: 0; margin: 24px 0 0; display: grid; gap: 12px; }
.check-list li { padding-left: 32px; position: relative; font-size: 19px; }
.check-list li::before { content: '✓'; position: absolute; left: 0; color: var(--color-primary); font-weight: 700; }
.table-wrap { max-width: var(--container-wide); margin: 0 auto; overflow-x: auto; }
.clean-table { width: 100%; border-collapse: collapse; min-width: 720px; background: var(--color-canvas); border: 1px solid var(--color-hairline); }
.clean-table th, .clean-table td { padding: 18px 20px; border-bottom: 1px solid var(--color-hairline); text-align: left; vertical-align: top; }
.clean-table th { width: 220px; font-weight: 600; background: var(--color-surface-pearl); }
.flow-list { counter-reset: steps; max-width: 1100px; margin: 0 auto; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(4, minmax(0,1fr)); gap: 24px; }
.flow-list li { background: var(--color-canvas); border: 1px solid var(--color-hairline); border-radius: var(--radius-lg); padding: 24px; }
.flow-list span { display: inline-grid; place-items: center; width: 36px; height: 36px; border-radius: var(--radius-pill); background: var(--color-primary); color: #fff; margin-bottom: 16px; }
.flow-list strong { display: block; margin-bottom: 8px; }
.faq-list { max-width: var(--container-text); margin: 0 auto; display: grid; gap: 10px; }
.faq-list details { background: var(--color-canvas); border: 1px solid var(--color-hairline); border-radius: var(--radius-lg); padding: 0; }
.faq-list summary { cursor: pointer; padding: 18px 22px; font-weight: 600; }
.faq-list p { padding: 0 22px 20px; color: var(--color-ink-muted-80); }
.page-title { text-align: center; }
.cta-band { text-align: center; }
.contact-form { max-width: 980px; margin: 0 auto; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.contact-form label, .contact-form fieldset { display: grid; gap: 8px; font-weight: 600; }
.contact-form input, .contact-form select, .contact-form textarea { width: 100%; min-height: 44px; border: 1px solid var(--color-hairline); border-radius: var(--radius-md); padding: 12px 14px; font: inherit; background: #fff; }
.contact-form .full, .contact-form fieldset { grid-column: 1 / -1; }
.contact-form fieldset { border: 1px solid var(--color-hairline); border-radius: var(--radius-lg); padding: 18px; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); }
.contact-form fieldset label { display: flex; align-items: center; gap: 8px; font-weight: 400; }
.contact-form fieldset input[type="checkbox"] { min-height: auto; width: auto; }
.form-note { color: var(--color-ink-muted-48); font-size: 14px; }
.news-list { max-width: var(--container-text); margin: 0 auto; }
.news-item { border-top: 1px solid var(--color-hairline); padding-top: 32px; }
.news-item time { color: var(--color-ink-muted-48); font-size: 14px; }

/* Legal / policy pages */
.tile.legal-text {
  max-width: none;
  margin: 0;
}

.legal-text article {
  max-width: var(--container-text);
  margin: 0 auto;
  border-bottom: 1px solid var(--color-hairline);
  padding: 32px 0;
}

.legal-text h2 {
  font-size: var(--type-display-md);
}

.site-footer { background: var(--color-canvas-parchment); color: var(--color-ink-muted-80); padding: 64px 24px 28px; }
.footer-inner { max-width: var(--container-wide); margin: 0 auto; display: grid; grid-template-columns: minmax(0, 1fr) minmax(320px, 1.4fr); gap: 48px; }
.footer-brand { color: var(--color-ink); margin-bottom: 12px; }
.footer-nav { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px 24px; }
.footer-nav a, .sns-links a { color: var(--color-ink-muted-80); text-decoration: none; line-height: 2.2; }
.sns-links { display: flex; gap: 18px; flex-wrap: wrap; }
.footer-legal { max-width: var(--container-wide); margin: 40px auto 0; padding-top: 18px; border-top: 1px solid var(--color-hairline); display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; color: var(--color-ink-muted-48); font-size: 12px; }
@media (max-width: 1100px) { .cols-4, .cols-5 { grid-template-columns: repeat(2, minmax(0,1fr)); } .flow-list { grid-template-columns: repeat(2, minmax(0,1fr)); } }
@media (max-width: 900px) { .desktop-nav, .nav-cta { display: none; } .mobile-nav { display: block; margin-left: auto; } .global-nav { padding: 0 16px; } .hero, .split { grid-template-columns: 1fr; min-height: auto; } .hero-copy { order: 1; } .hero-visual { order: 2; } .sub-nav span { display: none; } .photo-tile { min-height: 360px; } .footer-inner { grid-template-columns: 1fr; } }
@media (max-width: 640px) { .tile { padding-left: 20px; padding-right: 20px; } .cols-3, .cols-4, .cols-5, .flow-list, .contact-form { grid-template-columns: 1fr; } .footer-nav { grid-template-columns: repeat(2, minmax(0,1fr)); } .clean-table { min-width: 640px; } }


/* SilverArcs / developer information */
.company-note {
  margin-top: 18px;
  color: var(--color-ink-muted-48);
  font-size: 14px;
}
.company-links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 18px;
}
.company-links.left {
  justify-content: flex-start;
}
.company-links .text-link {
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-pill);
  padding: 9px 14px;
  background: var(--color-canvas);
}
.tile-dark .company-links .text-link {
  background: transparent;
  border-color: rgba(255,255,255,.22);
  color: var(--color-primary-on-dark);
}
.meta-list {
  display: grid;
  gap: 10px;
  margin: 0;
}
.meta-list div {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--color-hairline);
}
.meta-list dt { color: var(--color-ink-muted-48); font-weight: 600; }
.meta-list dd { margin: 0; }
.footer-developer {
  margin-top: 16px;
  font-size: 14px;
  color: var(--color-ink-muted-48);
}
.footer-developer a {
  color: var(--color-primary);
  text-decoration: none;
}
.footer-developer a:hover { text-decoration: underline; }
@media (max-width: 640px) {
  .meta-list div { grid-template-columns: 1fr; gap: 4px; }
}


/* Contact form API states */
.form-alert {
  grid-column: 1 / -1;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: 14px 16px;
  font-weight: 600;
  background: var(--color-canvas);
}
.form-alert.info {
  color: var(--color-primary);
  border-color: rgba(0, 102, 204, .24);
  background: rgba(0, 102, 204, .06);
}
.form-alert.success {
  color: #166534;
  border-color: #bbf7d0;
  background: #ecfdf3;
}
.form-alert.error {
  color: #991b1b;
  border-color: #fecaca;
  background: #fef2f2;
}
.contact-form .honeypot {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.consent-line {
  display: flex !important;
  grid-template-columns: auto 1fr !important;
  align-items: flex-start;
  gap: 10px !important;
  font-weight: 400 !important;
}
.consent-line input[type="checkbox"] {
  width: auto;
  min-height: auto;
  margin-top: 5px;
}
.button[disabled] {
  opacity: .58;
  cursor: not-allowed;
}