/* C direction: near-black / white, Helvetica-style grotesk + restrained serif.
   Spacing: 8 / 16 / 24 / 32 / 48 / 64 / 96. No external fonts or libraries. */
:root {
  color-scheme: dark;
  --background: #111111;
  --foreground: #f3f2ee;
  --secondary: #b9b9b5;
  --quiet: #91918d;
  --rule: #343433;
  --sans: "Helvetica Neue", Helvetica, "PingFang SC", "Microsoft YaHei", sans-serif;
  --serif: "Baskerville", "Iowan Old Style", "Times New Roman", serif;
}
* { box-sizing: border-box; }
html { min-width: 320px; }
body { margin: 0; background: var(--background); color: var(--foreground); font-family: var(--sans); -webkit-font-smoothing: antialiased; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; }
a, button { touch-action: manipulation; }
::selection { background: var(--foreground); color: var(--background); }
:focus-visible { outline: 1px solid var(--foreground); outline-offset: 6px; }
[tabindex="-1"]:focus { outline: none; }
[hidden] { display: none !important; }
.skip-link { position: fixed; z-index: 10; top: 12px; left: 16px; padding: 12px 20px; background: var(--foreground); color: var(--background); transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }
.site-shell { max-width: 1600px; min-height: 100svh; margin: 0 auto; padding: 0 clamp(24px, 6vw, 96px); display: flex; flex-direction: column; }
.site-header { min-height: 104px; display: flex; align-items: center; justify-content: space-between; gap: 32px; border-bottom: 1px solid var(--rule); }
.brand { display: inline-flex; align-items: center; gap: 16px; min-height: 44px; font-size: 15px; font-weight: 600; letter-spacing: .065em; white-space: nowrap; }
.brand-logo { display: block; max-width: 100%; height: auto; filter: invert(1); }
.header-mother-logo { display: block; width: 64px; height: auto; flex-shrink: 0; }
.home-logo { width: clamp(240px, 42vw, 560px); }
.about-logo { width: clamp(240px, 38vw, 520px); }
.header-controls { display: flex; align-items: center; gap: 32px; }
.navigation { display: flex; align-items: center; gap: 32px; }
.navigation > a, .nav-trigger { position: relative; display: flex; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; font-size: 13px; color: var(--secondary); white-space: nowrap; transition: color 160ms ease; }
.navigation > a:hover, .navigation > a[aria-current="page"], .nav-trigger:hover, .product-dropdown[data-active="true"] > summary { color: var(--foreground); }
.navigation > a::after, .nav-trigger::after { content: ""; position: absolute; left: 0; right: 0; bottom: 3px; height: 1px; background: currentColor; transform: scaleX(0); transform-origin: left; transition: transform 160ms ease; }
.navigation > a[aria-current="page"]::after, .product-dropdown[data-active="true"] > summary::after { transform: scaleX(1); }
.dropdown { position: relative; }
.dropdown summary { list-style: none; cursor: pointer; gap: 9px; }
.dropdown summary::-webkit-details-marker { display: none; }
.chevron { width: 6px; height: 6px; border-right: 1px solid currentColor; border-bottom: 1px solid currentColor; transform: translateY(-2px) rotate(45deg); }
.dropdown[open] > summary .chevron { transform: translateY(1px) rotate(225deg); }
.dropdown-panel { position: absolute; z-index: 5; top: calc(100% + 12px); left: -16px; min-width: 180px; padding: 6px; background: #181818; border: 1px solid var(--rule); }
.dropdown-panel a, .dropdown-panel button { display: flex; align-items: center; min-height: 44px; width: 100%; border: 0; border-radius: 0; padding: 10px 12px; color: var(--secondary); background: transparent; font-size: 13px; text-align: left; white-space: nowrap; }
.dropdown-panel a:hover, .dropdown-panel button:hover, .dropdown-panel a[aria-current="page"], .dropdown-panel button[aria-pressed="true"] { color: var(--foreground); background: #242424; }
.language-switch { display: flex; align-items: center; justify-content: center; min-height: 44px; min-width: 64px; padding-left: 24px; border-left: 1px solid var(--rule); color: var(--foreground); font-size: 12px; }
.language-options { left: auto; right: 0; min-width: 136px; }
main { display: flex; flex: 1; }
.page { width: 100%; min-height: max(620px, calc(100svh - 202px)); }
.home-page { position: relative; isolation: isolate; display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr); align-content: center; column-gap: 48px; overflow: hidden; padding: 80px 0 88px; }
.home-content { display: contents; }
.home-heading { grid-column: 1 / -1; grid-row: 1; margin: 0 0 40px; font-size: clamp(32px, 4.5vw, 64px); font-weight: 500; line-height: 1.1; letter-spacing: -.055em; white-space: nowrap; }
.slogan { grid-column: 1; grid-row: 2; margin: 0; color: var(--secondary); font-family: var(--serif); font-size: clamp(20px, 1.8vw, 25px); font-weight: 400; line-height: 1.6; letter-spacing: -.015em; }
.slogan span { display: block; }
.home-watermark { grid-column: 2; grid-row: 2; align-self: center; width: 100%; aspect-ratio: 776 / 160; background: url("preview-assets/shiro-wordmark.svg") center / contain no-repeat; opacity: .075; pointer-events: none; }
.page-heading { margin: 0; font-size: clamp(48px, 5.4vw, 80px); font-weight: 400; line-height: 1.1; letter-spacing: -.055em; text-wrap: balance; }
.product-page { display: grid; grid-template-columns: minmax(160px, 280px) minmax(0, 580px); justify-content: center; align-content: center; align-items: center; gap: clamp(48px, 8vw, 128px); padding: 96px 0; }
.product-icon img { display: block; width: 100%; height: auto; border-radius: 22%; }
.product-content .page-heading { font-size: clamp(40px, 4.1vw, 64px); }
.release-status { margin: 32px 0 20px; font-size: 13px; line-height: 1.6; letter-spacing: .02em; }
.body-copy { max-width: 480px; margin: 0; color: var(--secondary); font-size: 17px; line-height: 1.9; text-wrap: pretty; }
.about-page { display: grid; grid-template-columns: minmax(0, 1fr); gap: 48px; align-content: center; padding: 80px 0; }
.about-heading-block .page-heading { white-space: nowrap; }
.section-label { margin: 0 0 32px; color: var(--quiet); font-size: 12px; }
.about-content { width: min(100%, 760px); margin-left: auto; }
.about-introduction { margin: 0; font-size: clamp(21px, 2.1vw, 30px); font-weight: 400; line-height: 1.65; text-wrap: pretty; }
.company-information { max-width: 600px; margin-top: 64px; padding-top: 24px; border-top: 1px solid var(--rule); }
.company-information p { margin: 0; color: var(--quiet); font-size: 13px; line-height: 1.85; }
.site-footer { position: relative; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 16px; min-height: 98px; padding: 24px 0; border-top: 1px solid var(--rule); font-size: 11px; color: var(--quiet); }
.copyright { grid-column: 1; }
.icp-link { grid-column: 2; display: inline-flex; align-items: center; min-height: 44px; text-align: center; }
.icp-link:hover { color: var(--foreground); text-decoration: underline; text-underline-offset: 4px; }
@media (max-width: 860px) {
  .site-header { min-height: 96px; gap: 24px; }
  .header-controls, .navigation { gap: 20px; }
  .brand { font-size: 12px; }
  .navigation > a, .nav-trigger { font-size: 12px; }
  .language-switch { padding-left: 16px; }
  .product-page { grid-template-columns: minmax(140px, 220px) minmax(0, 1fr); gap: 40px; }
  .about-page { gap: 40px; }
  .home-page { column-gap: 32px; }
}
@media (max-width: 620px) {
  .site-shell { padding: 0 24px; }
  .site-header { padding: 20px 0 12px; flex-wrap: wrap; gap: 8px; }
  .brand { min-height: 44px; font-size: 13px; gap: 12px; }
  .header-mother-logo { width: 56px; }
  .header-controls { width: 100%; justify-content: space-between; gap: 16px; }
  .navigation { flex: 1; justify-content: space-between; gap: 12px; }
  .navigation > a, .nav-trigger { min-height: 48px; font-size: 12px; }
  .language-switch { min-height: 44px; min-width: 44px; padding-left: 16px; }
  .page { min-height: max(520px, calc(100svh - 252px)); }
  .home-page { grid-template-columns: minmax(0, 1fr); padding: 64px 0 56px; align-content: center; }
  .home-heading { font-size: clamp(27px, 7.5vw, 46px); margin-bottom: 40px; }
  .slogan { font-size: 21px; line-height: 1.6; }
  .home-watermark { grid-column: 1; grid-row: 3; width: 100%; margin-top: 48px; opacity: .055; }
  .product-page { grid-template-columns: 1fr; justify-items: start; align-content: center; gap: 40px; padding: 64px 0 80px; }
  .product-icon { width: 144px; }
  .product-content .page-heading { font-size: clamp(34px, 9vw, 48px); }
  .release-status { margin: 24px 0 16px; }
  .body-copy { font-size: 16px; line-height: 1.9; }
  .about-page { grid-template-columns: 1fr; gap: 40px; padding: 64px 0 80px; }
  .section-label { margin-bottom: 24px; }
  .page-heading { font-size: 54px; }
  .about-heading-block .page-heading { font-size: clamp(28px, 8vw, 44px); }
  .about-introduction { font-size: 22px; }
  .company-information { margin-top: 48px; }
  .site-footer { grid-template-columns: 1fr; gap: 0; justify-items: center; padding: 20px 0; min-height: 112px; }
  .copyright, .icp-link { grid-column: 1; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; scroll-behavior: auto !important; }
}