:root {
  color-scheme: dark;
  --bg: #0a0a0a;
  --bg-raised: #101010;
  --surface: #141414;
  --surface-strong: #1b1b1b;
  --text: #ffffff;
  --text-soft: #e5e7eb;
  --muted: #9ca3af;
  --primary: #ff6b35;
  --primary-hover: #e55a2b;
  --accent: #22c55e;
  --line: #262626;
  --line-strong: #3a3a3a;
  --shadow: 0 18px 48px rgba(0, 0, 0, .34);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; color: var(--text); background: var(--bg); font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif; }
body { margin: 0; min-width: 320px; overflow-x: hidden; background: var(--bg); font-size: 16px; line-height: 1.65; }
a { color: inherit; text-decoration: none; }
a, summary { cursor: pointer; touch-action: manipulation; }
:focus-visible { outline: 3px solid rgba(255, 107, 53, .72); outline-offset: 4px; }
h1, h2, h3, h4, p { margin-top: 0; }
h1, h2, h3, h4 { color: var(--text); line-height: 1.14; letter-spacing: 0; }
h1 { margin-bottom: 24px; font-size: 4.6rem; font-weight: 880; }
h1 span { color: var(--text); }
h1 strong { color: var(--primary); font-weight: inherit; }
h2 { margin-bottom: 16px; font-size: 3.25rem; font-weight: 840; }
h3 { font-size: 1.22rem; }
p { color: var(--muted); }
.container { width: min(1240px, calc(100% - 48px)); margin-inline: auto; }
.section { padding: 112px 0; scroll-margin-top: 92px; }

.site-header { position: sticky; top: 0; z-index: 50; background: rgba(8, 8, 10, .92); border-bottom: 1px solid var(--line); backdrop-filter: blur(16px); }
.header-inner { min-height: 80px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { flex: none; color: var(--text); font-size: 1.48rem; font-weight: 900; }
.brand span { display: inline-block; color: var(--primary); font-size: 1.14em; line-height: 1; vertical-align: -.02em; }
.site-nav { display: flex; justify-content: center; gap: 6px 30px; }
.site-nav a, .header-action { display: inline-flex; align-items: center; min-height: 48px; font-size: .9rem; font-weight: 700; white-space: nowrap; }
.site-nav a { color: var(--muted); transition: color .2s ease; }
.site-nav a:hover, .site-nav a.is-active { color: var(--primary); }
.header-action { padding: 0 22px; color: #fff; background: var(--primary); border-radius: 6px; box-shadow: 0 10px 28px rgba(255, 107, 53, .24); transition: background-color .2s ease, box-shadow .2s ease; }
.header-action:hover { background: var(--primary-hover); box-shadow: 0 12px 34px rgba(255, 107, 53, .32); }

.hero { position: relative; isolation: isolate; display: flex; align-items: center; min-height: min(780px, calc(100dvh - 80px)); overflow: hidden; background: var(--bg); }
.hero-stage { position: relative; width: 100%; }
.hero-grid { position: relative; z-index: 1; display: grid; grid-template-columns: repeat(2, minmax(0, 620px)); align-items: center; }
.hero-copy { position: relative; z-index: 1; width: 100%; max-width: 620px; margin-left: 15rem; }
.hero-visual { position: absolute; top: 50%; left: calc(50% - 160px); z-index: 0; width: clamp(500px, min(60vw, calc(100dvh - 120px)), 720px); aspect-ratio: 1; opacity: .7; transform: translateY(-50%); background-image: url("../images/hero-main.webp"); background-position: right center; background-repeat: no-repeat; background-size: contain; -webkit-mask-image: linear-gradient(to right, transparent 0, #000 14%, #000 100%); mask-image: linear-gradient(to right, transparent 0, #000 14%, #000 100%); }
.hero-visual::after { position: absolute; inset: 0; content: ""; pointer-events: none; background: linear-gradient(to right, transparent 76%, var(--bg) 100%), linear-gradient(to bottom, transparent 68%, var(--bg) 100%); }
.hero h1 { margin-bottom: 32px; }
.lead { max-width: 37rem; margin-bottom: 0; color: var(--muted); font-size: 1.06rem; line-height: 1.85; }
.action-row { display: flex; flex-wrap: wrap; gap: 14px; margin: 40px 0 0; }
.button { display: inline-flex; justify-content: center; align-items: center; gap: 24px; min-height: 54px; padding: 10px 24px; border: 1px solid var(--line-strong); border-radius: 6px; font-weight: 780; transition: color .2s ease, background-color .2s ease, border-color .2s ease, box-shadow .2s ease; }
.button-primary { gap: 10px; min-width: 220px; color: #fff; background: var(--primary); border-color: var(--primary); box-shadow: 0 12px 30px rgba(255, 107, 53, .22); }
.button-icon { flex: none; width: 20px; height: 20px; fill: currentColor; }
.button-primary:hover { background: var(--primary-hover); border-color: var(--primary-hover); box-shadow: 0 16px 36px rgba(255, 107, 53, .3); }
.button-secondary { color: var(--text); background: transparent; }
.button-secondary:hover { color: #fff; background: var(--surface-strong); border-color: #555560; }
#discover { background: var(--bg-raised); }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 48px; margin-bottom: 48px; text-align: left; }
.section-heading > div { max-width: 640px; }
.section-heading h2 { margin-bottom: 12px; }
.section-heading h2 + p { max-width: 540px; margin: 0; font-size: 1.02rem; }
#discover .section-heading { display: block; text-align: center; }
#discover .section-heading > div { margin-inline: auto; }
#discover .section-heading h2 + p { margin-inline: auto; }
.genre-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px; }
.genre-card { min-width: 0; overflow: hidden; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; transition: transform .3s ease, border-color .3s ease, background-color .3s ease, box-shadow .3s ease; }
.genre-card:hover { transform: translateY(-4px); background: var(--surface-strong); border-color: var(--primary); box-shadow: 0 16px 36px rgba(255, 107, 53, .18); }
.genre-image { aspect-ratio: 3 / 4; overflow: hidden; }
.genre-image img { width: 100%; height: 100%; object-fit: cover; object-position: center; transition: transform .5s cubic-bezier(.4, 0, .2, 1); }
.genre-card:hover .genre-image img { transform: scale(1.1); }
.genre-text { padding: 22px; border-top: 1px solid var(--line); }
.genre-text h3 { margin-bottom: 9px; font-size: 1.18rem; }
.genre-text p { margin-bottom: 0; font-size: .9rem; }
.scenario-grid { display: grid; grid-template-columns: 1.05fr repeat(3, minmax(0, 1fr)); gap: 0; margin-top: 40px; overflow: hidden; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; }
.scenario-intro, .scenario-grid article { min-width: 0; padding: 30px; }
.scenario-grid article { border-left: 1px solid var(--line); }
.scenario-intro h3 { margin-bottom: 12px; font-size: 1.5rem; }
.scenario-intro p { margin: 0; }
.scenario-grid article > span { color: var(--primary); font-size: .75rem; font-weight: 800; letter-spacing: .05em; }
.scenario-grid h4 { margin: 20px 0 12px; font-size: 1.1rem; }
.scenario-grid p { margin-bottom: 0; font-size: .9rem; }

.features { background: var(--bg); }
.capability-intro { max-width: 680px; margin: 0 auto 52px; text-align: center; }
.capability-intro h2 { margin-bottom: 16px; }
.capability-intro p { margin: 0; font-size: 1.02rem; }
.capability-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.capability-grid article { min-height: 250px; padding: 30px; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; transition: transform .3s ease, border-color .3s ease, background-color .3s ease, box-shadow .3s ease; }
.capability-grid article:hover { transform: translateY(-4px); color: #fff; background: var(--primary); border-color: var(--primary); box-shadow: 0 16px 36px rgba(255, 107, 53, .22); }
.capability-grid article:hover h3 { color: #fff; }
.capability-grid article:hover p, .capability-grid article:hover .capability-index { color: rgba(255, 255, 255, .88); }
.capability-index { display: block; margin-bottom: 54px; color: var(--primary); font-size: .76rem; font-weight: 850; letter-spacing: .08em; }
.capability-grid h3 { margin-bottom: 12px; font-size: 1.3rem; }
.capability-grid p { margin: 0; font-size: .92rem; }

.faq { background: var(--bg-raised); }
.faq-grid { display: grid; grid-template-columns: minmax(0, .72fr) minmax(0, 1.28fr); gap: 10%; align-items: start; }
.faq-grid > div:first-child { position: sticky; top: 124px; max-width: 420px; }
.faq-grid > div:first-child p { font-size: 1.02rem; }
.faq-list { display: grid; gap: 12px; }
.faq-list details { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; transition: border-color .2s ease, background-color .2s ease; }
.faq-list details:hover, .faq-list details[open] { background: var(--surface-strong); border-color: var(--primary); }
.faq-list summary { position: relative; min-height: 70px; padding: 21px 58px 21px 22px; color: var(--text); font-weight: 760; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { position: absolute; top: 50%; right: 20px; content: "+"; color: var(--primary); font-size: 1.45rem; font-weight: 400; transform: translateY(-50%); }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { padding: 0 58px 22px 22px; margin: 0; }

.download { padding-block: 96px; color: var(--text); background: var(--bg); }
.download-inner { padding: 72px 48px; text-align: center; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; box-shadow: var(--shadow); }
.download-inner > div:first-child { max-width: 680px; margin-inline: auto; }
.download h2 { color: var(--text); }
.download-inner h2 { margin-bottom: 14px; }
.download-inner p:last-child { margin-bottom: 0; color: var(--muted); }
.download .button { min-width: 220px; margin-top: 32px; color: #fff; background: var(--primary); border-color: var(--primary); box-shadow: 0 12px 30px rgba(255, 107, 53, .2); }
.download .button:hover { color: #fff; background: var(--primary-hover); border-color: var(--primary-hover); }

.site-footer { padding: 52px 0; background: #070707; border-top: 1px solid var(--line); }
.footer-inner { display: flex; align-items: center; gap: 24px; flex-wrap: wrap; color: var(--text); }
.footer-inner .brand span { color: var(--primary); }
.footer-inner p { margin: 0; color: var(--muted); }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 12px 22px; margin-left: auto; }
.site-footer nav a { display: inline-flex; align-items: center; min-height: 44px; color: var(--muted); font-size: .88rem; transition: color .2s ease; }
.site-footer nav a:hover { color: var(--text); }

@media (max-width: 1100px) {
  h1 { font-size: 4rem; }
  h2 { font-size: 2.8rem; }
  .hero-copy { margin-left: 0; }
  .hero-visual { left: calc(50% - 150px); opacity: .6; }
}

@media (max-width: 1023px) {
  .header-inner { flex-wrap: wrap; gap: 0 20px; padding: 12px 0; }
  .site-nav { order: 3; width: 100%; justify-content: flex-start; gap: 4px 22px; }
  .hero { min-height: 660px; padding: 72px 0; }
  .hero-grid { grid-template-columns: minmax(0, 55fr) minmax(0, 45fr); }
  .hero-visual { left: calc(55% - 150px); }
  .genre-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .scenario-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .scenario-grid article { border-left: 1px solid var(--line); }
  .scenario-grid article:last-child { border-top: 1px solid var(--line); }
  .capability-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 768px) and (max-width: 850px) {
  .action-row { flex-direction: column; max-width: 390px; }
  .action-row .button { width: 100%; }
}

@media (max-width: 767px) {
  h2 { font-size: 2.3rem; }
  .container { width: min(100% - 32px, 560px); }
  .section { padding: 72px 0; }
  .header-inner { min-height: 72px; }
  .brand { font-size: 1.28rem; }
  .header-action { min-height: 36px; margin-left: auto; padding: 0 14px; }
  .site-nav { display: none; }
  .hero { min-height: 0; padding: 72px 0 64px; }
  .hero-grid { position: relative; display: block; }
  .hero h1 { margin-bottom: 18px; font-size: 2.55rem; overflow-wrap: anywhere; }
  .hero h1 strong { display: inline; }
  .lead { font-size: 1rem; }
  .action-row { flex-direction: column; gap: 8px; margin: 26px 0 0; }
  .action-row .button { width: 100%; min-height: 50px; }
  .action-row .button-secondary { background: transparent; border-color: transparent; }
  .hero-copy { max-width: none; padding-right: 0; padding-left: 0; }
  .hero-visual { right: -3rem; left: auto; width: min(92vw, 500px); opacity: .4; background-position: right bottom; -webkit-mask-image: linear-gradient(to right, transparent 0, #000 30%, #000 100%); mask-image: linear-gradient(to right, transparent 0, #000 30%, #000 100%); }
  .section-heading { display: block; margin-bottom: 34px; }
  .genre-grid { gap: 12px; }
  .genre-text { padding: 16px; }
  .genre-text h3 { font-size: 1.04rem; }
  .genre-text p { font-size: .82rem; }
  .scenario-grid { grid-template-columns: 1fr; margin-top: 28px; }
  .scenario-intro, .scenario-grid article { padding: 24px; }
  .scenario-grid article, .scenario-grid article:last-child { border-top: 1px solid var(--line); border-left: 0; }
  .scenario-grid h4 { margin-top: 12px; }
  .capability-intro { margin-bottom: 36px; }
  .capability-grid { grid-template-columns: 1fr; gap: 12px; }
  .capability-grid article { min-height: 0; padding: 22px; }
  .capability-index { margin-bottom: 24px; }
  .faq-grid { grid-template-columns: 1fr; gap: 28px; }
  .faq-grid > div:first-child { position: static; }
  .download { padding-block: 64px; }
  .download-inner { padding: 48px 20px; }
  .download .button { width: 100%; margin-top: 28px; }
  .site-footer nav { width: 100%; margin-left: 0; }
}

@media (max-width: 420px) {
  .header-action { font-size: .84rem; }
  .site-nav { gap: 0 16px; }
  .site-nav a { font-size: .84rem; }
  .genre-grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}