:root { color-scheme: dark; --background: #101213; --surface: #171a1c; --text: #f4f3ee; --muted: #b4b6b7; --accent: #f0c15c; --line: #373b3e; --page-width: 75rem; --page-gutter: clamp(1.25rem, 5vw, 5rem); }
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 6rem; }
body { margin: 0; background: var(--background); color: var(--text); font: 1rem/1.8 "Segoe UI", "Yu Gothic UI", "Meiryo", sans-serif; }
[hidden] { display: none !important; }
a { color: inherit; text-underline-offset: .25em; }
button { font: inherit; cursor: pointer; }
a, button, summary { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 5px; }
::selection { background: var(--accent); color: var(--background); }
p { margin: 0 0 1rem; }
h1, h2, h3 { margin: 0; }
h2 { font-size: clamp(1.9rem, 3.8vw, 3.1rem); line-height: 1.45; letter-spacing: -.04em; font-weight: 650; }
h3 { font-size: 1.15rem; line-height: 1.6; font-weight: 650; }
code { font: .9rem/1.8 "Cascadia Code", Consolas, monospace; overflow-wrap: anywhere; }
.skip-link { position: fixed; top: -6rem; left: 1rem; z-index: 10; padding: .6rem 1rem; background: var(--accent); color: var(--background); }
.skip-link:focus { top: 1rem; }
.site-header { max-width: calc(var(--page-width) + var(--page-gutter) * 2); margin: auto; padding: 1.5rem var(--page-gutter); display: flex; align-items: center; gap: 2rem; }
.brand { text-decoration: none; font-size: 1.15rem; font-weight: 750; letter-spacing: -.025em; }
.brand-divider { margin: 0 .5rem; color: var(--accent); }
.brand-note { color: var(--muted); font-size: .875rem; font-weight: 400; letter-spacing: normal; }
nav { margin-left: auto; display: flex; flex-wrap: wrap; gap: 1.65rem; font-size: .875rem; }
nav a { text-decoration: none; }
nav a:hover, footer a:hover { color: var(--accent); }
.language-switch { display: flex; gap: .15rem; padding: .2rem; border: 1px solid var(--line); }
.language-switch button { background: none; color: var(--muted); border: 0; font-size: .875rem; padding: .25rem .6rem; min-height: 2.2rem; }
.language-switch button[aria-pressed="true"] { color: var(--background); background: var(--text); }
main, footer { width: calc(100% - var(--page-gutter) * 2); max-width: var(--page-width); margin: auto; }
.hero { padding: 4.5rem 0 5rem; }
.eyebrow, .section-number, .feature-index { font-size: .875rem; letter-spacing: .06em; }
.eyebrow { display: flex; align-items: center; gap: 1rem; color: var(--accent); margin-bottom: 2rem; }
.line-mark { width: 2.5rem; height: 1px; background: var(--accent); }
h1 { font-size: clamp(3rem, 10vw, 8.2rem); line-height: 1.03; font-weight: 700; letter-spacing: -.065em; overflow-wrap: anywhere; }
h1 > span:not(.title-period) { font-weight: 350; }
.hero-stage { display: grid; grid-template-columns: .85fr 1.15fr; align-items: center; gap: 2.5rem; }
.hero-stage h1 { font-size: clamp(3rem, 6.5vw, 6.5rem); }
.hero-visual { position: relative; display: block; overflow: hidden; }
.hero-visual img { display: block; width: 100%; height: auto; }
.play-mark { position: absolute; left: 50%; top: 50%; transform: translate(-50%,-50%); border-radius: 50%; display: grid; place-items: center; width: 3.5rem; height: 3.5rem; background: #111b; color: white; border: 1px solid #fffa; }
.hero-visual:hover .play-mark { background: #1f2b39; }
.video-grid { max-width: 60rem; }
.video-grid figure + figure { margin-top: 2rem; }
.video-grid figure, .media-gallery figure { margin: 0; min-width: 0; }
.video-grid video { display: block; width: 100%; aspect-ratio: 16/9; background: #0c1018; }
.video-grid figcaption { padding: 1rem 0; }
.video-grid figcaption p { color: var(--muted); font-size: .875rem; margin-top: .5rem; }
.media-gallery { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 1.2rem; margin-top: 2rem; }
.media-gallery img { display: block; width: 100%; height: auto; }
.media-gallery figcaption { padding-top: .75rem; color: var(--muted); font-size: .875rem; }
@media (max-width: 60rem) { .hero-stage { grid-template-columns: 1fr; } .hero-stage h1 { font-size: clamp(3rem,10vw,6rem); } }
@media (max-width: 40rem) { .video-grid, .media-gallery { grid-template-columns: 1fr; } }
.title-period { color: var(--accent); }
.hero-bottom { margin-top: 3.5rem; padding-top: 2rem; border-top: 1px solid var(--line); display: grid; grid-template-columns: 1.5fr 1fr; gap: 5rem; }
.hero-summary > p { max-width: 38rem; color: var(--muted); }
.hero-summary .hero-lead { color: var(--text); font-size: 1.25rem; font-weight: 550; margin-bottom: .8rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 1.7rem; }
.button { display: inline-flex; justify-content: center; align-items: center; text-decoration: none; font-size: .875rem; font-weight: 600; min-height: 3rem; padding: .65rem 1.2rem; border: 1px solid var(--line); }
.primary { background: var(--accent); border-color: var(--accent); color: var(--background); }
.primary:hover { background: #ffcf6e; border-color: #ffcf6e; }
.secondary:hover { background: var(--surface); }
.hero-spec { margin: 0; }
.hero-spec > div { padding: .65rem 0; display: grid; grid-template-columns: 6.5rem minmax(0, 1fr); gap: 1.3rem; border-bottom: 1px solid var(--line); }
dt { color: var(--muted); font-size: .875rem; }
dd { margin: 0; font-size: .875rem; }
small { display: block; color: var(--muted); font-size: .8125rem; line-height: 1.65; margin-top: .25rem; }
.section { border-top: 1px solid var(--line); padding: 4.5rem 0; }
.section-heading { max-width: 48rem; margin-bottom: 2.75rem; }
.section-number { color: var(--accent); margin-bottom: 1rem; }
.section-heading > p:last-child:not(.section-number) { color: var(--muted); margin-top: 1.25rem; }
.feature-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 3rem; }
.feature-grid article { padding: 1.6rem 0; border-top: 1px solid var(--line); }
.feature-index { display: block; color: var(--muted); margin-bottom: .7rem; }
.feature-grid h3 { margin-bottom: .8rem; }
.feature-grid p { color: var(--muted); }
.feature-grid .feature-note { font-size: .875rem; color: var(--accent); margin-bottom: .1rem; }
.modes { margin-top: 1.7rem; padding: 1.3rem 1.6rem; background: var(--surface); display: flex; gap: 2rem; align-items: baseline; }
.modes p { color: var(--muted); font-size: .875rem; margin: 0; flex-shrink: 0; }
.modes ul { margin: 0; padding: 0; list-style: none; display: flex; flex-wrap: wrap; gap: .45rem 1.1rem; font-size: .875rem; }
.compatibility-list > div { display: grid; grid-template-columns: 16rem 1fr; gap: 2rem; padding: 1.6rem 0; border-top: 1px solid var(--line); }
.compatibility-list p { color: var(--muted); margin: 0; }
.limitations { margin-top: 2rem; padding: 1.8rem 2rem; border: 1px solid var(--line); }
.limitations > h3 { margin-bottom: 1.2rem; }
details { border-top: 1px solid var(--line); }
summary { cursor: pointer; padding: 1rem 0; font-size: 1rem; font-weight: 550; }
summary:hover { color: var(--accent); }
details p { color: var(--muted); margin-bottom: 1.3rem; }
.steps { padding: 0; margin: 0; list-style: none; counter-reset: workflow; display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
.steps li { counter-increment: workflow; border-top: 1px solid var(--line); padding-top: 1.5rem; }
.steps li::before { content: "0" counter(workflow); display: block; color: var(--accent); font: 2rem/1 Consolas, monospace; margin-bottom: 1.5rem; }
.steps h3 { margin-bottom: .8rem; }
.steps p { color: var(--muted); }
.documentation { margin-top: 2rem; border-bottom: 1px solid var(--line); }
.documentation dl { display: grid; grid-template-columns: 9rem 1fr; gap: 1rem 2rem; margin-bottom: 1.5rem; }
.support-grid { display: grid; grid-template-columns: 1.25fr 1fr; gap: 5rem; }
.support-grid p { color: var(--muted); }
.email { display: block; font-size: clamp(1rem, 2.5vw, 1.6rem); margin: 1.3rem 0; overflow-wrap: anywhere; }
.support-note { margin-top: .8rem; font-size: .875rem; }
.support-scope { padding-left: 2rem; border-left: 1px solid var(--line); }
.support-scope h3 { margin-bottom: .8rem; }
.support-scope p { margin-bottom: 1.6rem; }
footer { border-top: 1px solid var(--line); padding: 1.7rem 0; display: flex; align-items: baseline; gap: 2rem; }
footer p { color: var(--muted); font-size: .875rem; flex: 1; }
footer > a:last-child { font-size: .875rem; white-space: nowrap; }
@media (max-width: 60rem) {
  .site-header { gap: 1rem; flex-wrap: wrap; }
  .brand-note, .brand-divider { display: none; }
  nav { gap: 1rem; }
  .hero-bottom, .support-grid { gap: 2.5rem; }
  .compatibility-list > div { grid-template-columns: 12rem 1fr; }
  .hero-spec > div { grid-template-columns: 1fr; gap: .1rem; }
}
@media (max-width: 40rem) {
  .site-header { padding-top: 1rem; padding-bottom: 1rem; justify-content: space-between; }
  .language-switch { margin-left: auto; }
  nav { order: 3; width: 100%; margin-left: 0; padding-top: .4rem; }
  .hero { padding: 2.5rem 0 3rem; }
  h1 { font-size: clamp(2.8rem, 10vw, 4rem); }
  .hero-bottom { margin-top: 2rem; grid-template-columns: 1fr; gap: 2rem; }
  .hero-spec > div { grid-template-columns: 7rem minmax(0, 1fr); gap: .75rem; }
  .section { padding: 3rem 0; }
  .section-heading { margin-bottom: 2rem; }
  .feature-grid, .steps, .support-grid { grid-template-columns: 1fr; gap: 1.5rem; }
  .feature-grid { gap: 0; }
  .modes { display: block; padding: 1.2rem; }
  .modes p { margin-bottom: .65rem; }
  .compatibility-list > div { grid-template-columns: 1fr; gap: .65rem; }
  .limitations { padding: 1.3rem; }
  .documentation dl { grid-template-columns: 1fr; gap: .3rem; }
  .documentation dd { margin-bottom: 1rem; }
  .support-scope { padding-left: 0; padding-top: 1.5rem; border-left: 0; border-top: 1px solid var(--line); }
  footer { flex-wrap: wrap; gap: .7rem 1.5rem; }
  footer p { flex-basis: 100%; order: 3; margin: .4rem 0 0; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }