:root {
  --bg: #0a0a0c;
  --panel: #121215;
  --line: #2a2620;
  --text: #ece6da;
  --sub: #9f988c;
  --gold: #c9a86a;
  --gold-2: #e5cc95;
  --err: #ff8a7a;
  --serif: "Noto Serif JP", serif;
  --sans: "Noto Sans JP", system-ui, -apple-system, "Hiragino Sans", sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--sans); line-height: 1.8; -webkit-font-smoothing: antialiased; }
a { color: var(--gold-2); }
em { color: var(--gold); font-style: normal; }

.nav { position: sticky; top: 0; z-index: 5; display: flex; justify-content: space-between; align-items: center;
  padding: 14px 20px; background: rgba(10,10,12,.82); backdrop-filter: blur(10px); border-bottom: 1px solid var(--line); }
.logo { font-family: var(--serif); font-weight: 700; letter-spacing: .25em; color: var(--text); text-decoration: none; font-size: .95rem; }
.logo .kanji { color: var(--gold); letter-spacing: 0; margin-right: 6px; font-size: 1.2em; }
.lang { display: flex; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; }
.lang button { background: none; border: 0; color: var(--sub); padding: 6px 12px; font: inherit; font-size: .8rem; cursor: pointer; }
.lang button[aria-pressed=true] { background: var(--gold); color: #111; font-weight: 700; }

.hero { position: relative; overflow: hidden; min-height: 88vh; display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  align-items: center; gap: 12px; padding: 64px 24px 48px; max-width: 1280px; margin: 0 auto; }
.hero-text { position: relative; z-index: 1; display: flex; flex-direction: column; }
.hero::before { content: ""; position: absolute; inset: -20%; background: radial-gradient(circle at 70% 40%, rgba(201,168,106,.14), transparent 55%); pointer-events: none; }
.hero-kanji { position: absolute; right: -2%; top: 50%; transform: translateY(-50%); font-family: var(--serif); font-weight: 700;
  font-size: min(62vw, 560px); line-height: 1; color: transparent; -webkit-text-stroke: 1px rgba(201,168,106,.28); user-select: none; }
.eyebrow { color: var(--gold); letter-spacing: .3em; font-size: .75rem; margin: 0 0 18px; position: relative; }
h1 { font-family: var(--serif); font-weight: 700; font-size: clamp(2.4rem, 8vw, 5rem); line-height: 1.25; margin: 0; position: relative; }
.lead { color: var(--sub); font-size: clamp(1rem, 2.4vw, 1.2rem); margin: 22px 0 34px; position: relative; max-width: 34em; }
.cta { display: inline-block; align-self: flex-start; background: linear-gradient(90deg, var(--gold), var(--gold-2)); color: #111; font-weight: 700;
  padding: 16px 34px; border-radius: 999px; text-decoration: none; border: 0; font: inherit; font-weight: 700; cursor: pointer; position: relative;
  box-shadow: 0 10px 30px rgba(201,168,106,.2); }
.cta:disabled { opacity: .6; }
.count { color: var(--gold); margin-top: 16px; position: relative; font-size: .9rem; }

.block { max-width: 1080px; margin: 0 auto; padding: 72px 24px; border-top: 1px solid var(--line); }
h2 { font-family: var(--serif); font-size: clamp(1.5rem, 4vw, 2.3rem); line-height: 1.45; margin: 0 0 16px; }
.sub { color: var(--sub); max-width: 40em; }
.sub strong { color: var(--gold-2); font-weight: 500; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 16px; margin-top: 36px; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: 16px; padding: 26px; }
.card .num { font-family: var(--serif); color: var(--gold); font-size: 1.6rem; }
.card h3 { font-family: var(--serif); margin: 8px 0; font-size: 1.15rem; }
.card p { color: var(--sub); margin: 0; font-size: .92rem; }

.split { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 32px; }
.tag { color: var(--gold); letter-spacing: .25em; font-size: .72rem; margin: 0 0 6px; }
.side h3 { font-family: var(--serif); font-size: 1.35rem; margin: 0 0 12px; }
.side ul, .perks { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.side li { padding-left: 1.2em; position: relative; color: var(--sub); }
.side li::before { content: "—"; position: absolute; left: 0; color: var(--gold); }

.founding { text-align: center; }
.founding .perks { justify-content: center; margin-top: 20px; font-size: 1.05rem; }

form { display: grid; gap: 18px; max-width: 560px; margin-top: 24px; }
label, legend { display: block; font-size: .9rem; color: var(--sub); }
fieldset { border: 0; padding: 0; margin: 0; }
input[type=email], input[type=text] { width: 100%; margin-top: 6px; background: var(--panel); border: 1px solid var(--line); border-radius: 12px;
  padding: 14px; color: var(--text); font: inherit; font-size: 16px; }
input:focus { outline: 2px solid var(--gold); outline-offset: 1px; }
.roles { display: grid; gap: 8px; margin-top: 8px; }
.role { display: flex; gap: 10px; align-items: center; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; color: var(--text); cursor: pointer; }
.role:has(input:checked) { border-color: var(--gold); }
input[type=radio], input[type=checkbox] { accent-color: var(--gold); width: 18px; height: 18px; flex: none; }
.consent { display: flex; gap: 10px; align-items: flex-start; font-size: .82rem; }
.consent input { margin-top: 4px; }
.hp { position: absolute; left: -9999px; width: 1px; height: 1px; opacity: 0; }
.msg { min-height: 1.5em; margin: 0; }
.msg.ok { color: var(--gold-2); }
.msg.err { color: var(--err); }

.foot { text-align: center; padding: 48px 24px 64px; border-top: 1px solid var(--line); color: var(--sub); font-size: .85rem; }
.foot .logo { display: inline-block; margin-bottom: 8px; }
.fine { font-size: .75rem; }

/* 3Dショールーム */
.showroom { margin: 0; position: relative; z-index: 1; }
.stage { position: relative; aspect-ratio: 4 / 3; width: 100%; }
.stage canvas { width: 100%; height: 100%; display: block;
  -webkit-mask-image: radial-gradient(ellipse 50% 50% at 50% 55%, #000 62%, transparent 100%); mask-image: radial-gradient(ellipse 50% 50% at 50% 55%, #000 62%, transparent 100%); touch-action: pan-y; cursor: grab; opacity: 0; transition: opacity 1.2s ease; }
.stage canvas:active { cursor: grabbing; }
.stage.ready canvas { opacity: 1; }
.stage.no-webgl { display: none; }
.showroom figcaption { display: flex; align-items: center; justify-content: center; gap: 16px; flex-wrap: wrap; margin-top: -6px; font-size: .75rem; color: var(--sub); }
.showroom .model { font-family: var(--serif); letter-spacing: .3em; color: var(--gold); }
.paints { display: flex; gap: 8px; }
.paints .lbl { font-size: .65rem; letter-spacing: .2em; color: var(--sub); align-self: center; margin-right: 2px; }
.calipers button { width: 18px; height: 18px; }
.door-btn { background: none; border: 1px solid var(--gold); color: var(--gold-2); border-radius: 999px; padding: 6px 14px; font: inherit; font-size: .75rem; cursor: pointer; }
.engine-btn { border-color: #c0120f; color: #ff9b8f; }
.engine-btn[aria-pressed=true] { background: #c0120f; color: #fff; }
.rev-btn { border-color: #ff6a3d; color: #ffb199; animation: pulse 1.2s infinite; }
@keyframes pulse { 50% { box-shadow: 0 0 14px rgba(255,106,61,.6); } }
.door-btn[aria-pressed=true] { background: var(--gold); color: #111; }
.paints button { width: 22px; height: 22px; border-radius: 50%; background: var(--c); border: 1px solid rgba(255,255,255,.25); cursor: pointer; padding: 0; }
.paints button[aria-pressed=true] { outline: 2px solid var(--gold); outline-offset: 2px; }

@media (max-width: 860px) {
  .hero { grid-template-columns: 1fr; min-height: auto; padding-top: 24px; }
  .showroom { order: -1; margin: 0 -24px; }
  .stage { aspect-ratio: 1 / 0.82; }
}
@media (max-width: 600px) {
  .hero-kanji { right: -18%; opacity: .8; }
  .cta { width: 100%; text-align: center; }
}

/* サウンド（BGM）ボタン：オンのとき金色のイコライザーが動く */
.nav-right { display: flex; align-items: center; gap: 10px; }
.sound-btn { display: inline-flex; align-items: center; gap: 8px; background: none; border: 1px solid var(--line); border-radius: 999px;
  color: var(--sub); padding: 6px 12px; font: inherit; font-size: .72rem; letter-spacing: .2em; cursor: pointer; }
.sound-btn[aria-pressed=true] { border-color: var(--gold); color: var(--gold-2); }
.sound-btn[hidden] { display: none; }
.eq { display: inline-flex; align-items: flex-end; gap: 2px; height: 12px; }
.eq i { display: block; width: 2px; height: 3px; background: currentColor; border-radius: 1px; }
.sound-on .eq i { animation: eq .9s ease-in-out infinite; }
.sound-on .eq i:nth-child(2) { animation-delay: -.3s; }
.sound-on .eq i:nth-child(3) { animation-delay: -.6s; }
.sound-on .eq i:nth-child(4) { animation-delay: -.15s; }
@keyframes eq { 0%, 100% { height: 3px; } 50% { height: 12px; } }
@media (max-width: 600px) { .sound-label { display: none; } }
@media (prefers-reduced-motion: reduce) { .sound-on .eq i { animation: none; height: 8px; } }