/* orbitaltone.com — 色は製品の PLEX（ADR 0107・src/os/gui/aurora/OaTheme.h）に揃える。
   書体（2026-10-15 五十嵐さん = 案 C）: 見出し = Source Serif 4（製品名の書体）・本文 = Geist・小さな印 = Geist Mono（いずれも SIL OFL 1.1・許諾文は fonts/） */
@font-face { font-family: "Geist"; src: url("fonts/Geist-VF.woff2") format("woff2"); font-weight: 100 900; font-display: swap; }
@font-face { font-family: "Geist Mono"; src: url("fonts/GeistMono-VF.woff2") format("woff2"); font-weight: 100 900; font-display: swap; }
@font-face { font-family: "Jost"; src: url("fonts/Jost-VF.woff2") format("woff2"); font-weight: 100 900; font-display: swap; }   /* 社名の字だけ（2026-10-15 五十嵐さん = Jost・円い O が ORBiTAL に重なる） */
@font-face { font-family: "Source Serif 4"; src: url("fonts/SourceSerif4-Semibold.woff2") format("woff2"); font-weight: 600; font-display: swap; }

:root {
  --sky-top: #03050b;      /* kSkyFlat / kHeroTop */
  --sky-mid: #060a16;      /* kZlSkyStop[1] */
  --sky-low: #0b1426;      /* kHeroBottom */
  --text: #e6ebf2;
  --muted: #9aa3b2;
  --faint: #5c6784;
  --line: #1c2436;
  --green: #5ef2a6;        /* Dynamics */
  --cyan: #4fd6f5;         /* Optimize */
  --violet: #8a6cf0;
  --serif: "Source Serif 4", Georgia, serif;
  --sans: "Geist", -apple-system, "Helvetica Neue", Arial, sans-serif;
  --mono: "Geist Mono", Menlo, Consolas, monospace;
  --brand: "Jost", "Geist", -apple-system, sans-serif;   /* 社名（左上のロゴと会社ページの見出し）= 2026-10-15 五十嵐さん */
}

* { box-sizing: border-box; }
html { background: var(--sky-top); overflow-x: clip; }
body { overflow-x: clip; }
body {
  margin: 0; color: var(--text); font-family: var(--sans); font-size: 16px; line-height: 1.6;
  background: linear-gradient(180deg, var(--sky-top) 0%, var(--sky-mid) 55%, var(--sky-low) 100%);
  min-height: 100vh; -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
#stars { position: fixed; inset: 0; width: 100%; height: 100%; z-index: 0; pointer-events: none; }
.wrap { position: relative; z-index: 1; max-width: 1080px; margin: 0 auto; padding: 0 24px; }

header.site { display: flex; align-items: center; justify-content: space-between; padding: 28px 0; }
.mark { white-space: nowrap; font-family: var(--brand); font-weight: 500; font-size: 19px; letter-spacing: 0.16em; text-decoration: none; }
nav a { font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted); text-decoration: none; margin-left: 28px; }
nav a:hover { color: var(--text); }

.kicker { font-family: var(--mono); font-size: 12px; letter-spacing: 0.22em; text-transform: uppercase; color: var(--muted); }
.kicker.brand-kicker { font-family: var(--brand); font-weight: 400; font-size: 15px; letter-spacing: 0.24em; text-transform: none; }   /* 社名は Jost・i は小文字のまま（2026-10-15） */

/* 1 画面目 = コンセプト（2026-10-14 五十嵐さん「Software-defined sound engineering」・説明は案 A） */
.hero { min-height: 86vh; display: flex; flex-direction: column; justify-content: center; padding: 40px 0 96px; position: relative; }
.hero h1 { font-family: var(--serif); font-weight: 600; font-size: clamp(44px, 7.4vw, 96px); line-height: 1.02; margin: 20px 0 28px; letter-spacing: -0.015em; max-width: 16ch; }
.nowrap { white-space: nowrap; }
.hero .sub { color: var(--muted); font-size: clamp(17px, 1.8vw, 20px); line-height: 1.65; max-width: 46ch; margin: 0; }
.hero .sub strong { color: var(--text); font-weight: 500; }

/* オーロラの帯（製品の主画面の稜線を思わせる程度・CSS だけ） */
.ribbon { position: absolute; left: -10%; right: -10%; bottom: 0; height: 300px; z-index: -1; filter: blur(30px); opacity: 0.55;
  -webkit-mask-image: linear-gradient(180deg, #000 0%, #000 45%, transparent 85%); mask-image: linear-gradient(180deg, #000 0%, #000 45%, transparent 85%);
  animation: breathe 9s ease-in-out infinite alternate; }
.ribbon::before { content: ""; position: absolute; inset: 0;
  background: linear-gradient(90deg, transparent 0%, #0f5a7a 18%, var(--green) 38%, var(--cyan) 55%, #5a2f8f 75%, transparent 100%);
  clip-path: polygon(0 55%, 12% 40%, 25% 46%, 38% 22%, 50% 34%, 62% 12%, 75% 30%, 88% 20%, 100% 38%, 100% 100%, 0 100%); }
@keyframes breathe { from { opacity: 0.38; transform: translateY(6px); } to { opacity: 0.6; transform: translateY(-6px); } }
@media (prefers-reduced-motion: reduce) { .ribbon { animation: none; } }

/* PRODUCTS = 製品ページへ。#1（第一弾）を横幅いっぱい = 最も強く */
.products { padding: 24px 0 96px; }
.products > .kicker { margin-bottom: 18px; }
.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.card { display: block; text-decoration: none; border: 1px solid var(--line); border-radius: 6px; padding: 32px; background: rgba(8, 11, 20, 0.6);
  transition: border-color 0.2s, background 0.2s; position: relative; }
.card:hover, .card:focus-visible { border-color: #33405a; background: rgba(12, 17, 30, 0.75); }
.card h2 { font-family: var(--serif); font-weight: 600; font-size: 44px; margin: 10px 0 6px; }
.card p { color: var(--muted); margin: 0; }
.card .when { margin-top: 20px; font-family: var(--mono); font-size: 12px; letter-spacing: 0.22em; color: var(--faint); text-transform: uppercase; }
.card .go { position: absolute; right: 28px; bottom: 26px; font-family: var(--mono); font-size: 12px; letter-spacing: 0.18em; color: var(--faint); text-transform: uppercase; }
.card:hover .go { color: var(--text); }
.card.first { isolation: isolate; grid-column: 1 / -1; padding: 48px 40px; min-height: 280px; display: flex; flex-direction: column; justify-content: flex-end; overflow: hidden; }
.card.first h2 { font-size: clamp(88px, 12vw, 140px); line-height: 0.95; margin: 12px 0 14px; }
.card.first p { font-size: 20px; color: var(--text); font-weight: 500; }
.card.first .when { color: var(--green); }
.card.first::after { content: ""; position: absolute; right: -8%; top: -30%; width: 60%; height: 160%; z-index: -1; filter: blur(60px); opacity: 0.35;
  background: radial-gradient(closest-side, var(--green), transparent 70%), radial-gradient(closest-side at 70% 60%, var(--cyan), transparent 70%); }

/* 画面には出さず、検索エンジンと読み上げにだけ渡す見出し */
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }

/* 製品ページ */
.teaser { margin: 22px 0 40px; border: 1px solid var(--line); border-radius: 6px; overflow: hidden; background: #000; aspect-ratio: 16 / 9; }
.teaser video { display: block; width: 100%; height: 100%; object-fit: cover; }
.product { min-height: 70vh; padding: 64px 0 96px; display: flex; flex-direction: column; justify-content: center; }
.product h1 { font-family: var(--serif); font-weight: 600; font-size: clamp(112px, 16vw, 180px); line-height: 0.95; margin: 14px 0 18px; }
.product .lead { font-size: clamp(20px, 2.6vw, 28px); font-weight: 500; max-width: 28ch; margin: 0 0 12px; }
.product .sub { color: var(--muted); max-width: 52ch; margin: 0; }
.product .when { margin-top: 36px; font-family: var(--mono); font-size: 13px; letter-spacing: 0.24em; text-transform: uppercase; color: var(--green); }
.back { display: inline-block; margin-top: 56px; font-family: var(--mono); font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--muted); text-decoration: none; }
.back:hover { color: var(--text); }

.about { border-top: 1px solid var(--line); padding: 72px 0; display: grid; grid-template-columns: 1fr 2fr; gap: 32px; }
.about > .kicker { padding-top: 10px; }
.about .proof { color: var(--text); font-size: 18px; font-weight: 500; }
.about h3 { font-family: var(--serif); font-weight: 600; font-size: clamp(30px, 4vw, 44px); line-height: 1.15; margin: 0 0 18px; }
.about p { color: var(--muted); margin: 0 0 12px; max-width: 60ch; }

footer.site { border-top: 1px solid var(--line); padding: 28px 0 40px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 13px; color: var(--faint); }
footer.site a { color: var(--muted); text-decoration: none; }

/* 会社ページ */
.page { padding: 64px 0 96px; }
.page h1 { font-family: var(--serif); font-weight: 600; font-size: 48px; margin: 12px 0 40px; }
.page h1.brand { font-family: var(--brand); font-weight: 500; font-size: 46px; letter-spacing: 0.06em; }
dl.facts { display: grid; grid-template-columns: 220px 1fr; margin: 0; border-top: 1px solid var(--line); }
dl.facts dt, dl.facts dd { padding: 18px 0; border-bottom: 1px solid var(--line); margin: 0; }
dl.facts dt { font-family: var(--mono); font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--muted); padding-top: 21px; }
dl.facts dd .ja { display: block; color: var(--muted); font-size: 14px; }

@media (max-width: 720px) {
  .grid, .about { grid-template-columns: 1fr; }
  .card.first { padding: 36px 24px; }
  dl.facts { grid-template-columns: 1fr; }
  dl.facts dt { border-bottom: 0; padding-bottom: 0; }
  nav a { margin-left: 10px; font-size: 10.5px; letter-spacing: 0.08em; }
  .mark { font-size: 15px; letter-spacing: 0.1em; }
  .page h1.brand { font-size: 30px; letter-spacing: 0.04em; }
  .wrap { padding: 0 16px; }
}

/* Contact の小窓 */
dialog.contact { border: 1px solid var(--line); border-radius: 8px; padding: 36px 40px 32px; width: min(440px, calc(100vw - 32px));
  background: #070a12; color: var(--text); box-shadow: 0 24px 80px rgba(0, 0, 0, 0.6); }
dialog.contact::backdrop { background: rgba(3, 5, 11, 0.72); backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); }
dialog.contact .addr { font-family: var(--mono); font-size: clamp(17px, 4.6vw, 22px); margin: 14px 0 26px; user-select: all; overflow-wrap: anywhere; }
dialog.contact .actions { display: flex; gap: 12px; flex-wrap: wrap; }
dialog.contact .actions > * { font: 500 13px/1 var(--sans); letter-spacing: 0.08em; padding: 12px 16px; border-radius: 4px; cursor: pointer; text-decoration: none; }
dialog.contact .copy { background: var(--green); color: #03050b; border: 0; }
dialog.contact .open { border: 1px solid var(--line); color: var(--muted); }
dialog.contact .open:hover { color: var(--text); }
dialog.contact .close { position: absolute; top: 10px; right: 14px; background: none; border: 0; color: var(--muted); font-size: 24px; cursor: pointer; }
dialog.contact .close:hover { color: var(--text); }