:root {
  color-scheme: dark;
  --bg: #080b13;
  --surface: #0f1420;
  --surface-soft: #141b29;
  --line: rgba(162, 179, 207, 0.15);
  --text: #f3f7ff;
  --muted: #9aa8bc;
  --blue: #5c7cff;
  --purple: #9167ff;
  --green: #42d69a;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Microsoft YaHei", sans-serif; }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
.icon-sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.ui-icon { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; flex: 0 0 auto; }

.site-header { width: min(1180px, calc(100% - 48px)); height: 76px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 19px; font-weight: 720; letter-spacing: .02em; }
.brand img { width: 32px; height: 32px; border-radius: 9px; }
nav { display: flex; gap: 34px; color: var(--muted); font-size: 14px; }
nav a { transition: color .2s ease; }
nav a:hover { color: var(--text); }

main { overflow: hidden; }
.hero { width: min(1180px, calc(100% - 48px)); min-height: 720px; margin: 0 auto; display: grid; grid-template-columns: .82fr 1.18fr; align-items: center; gap: 36px; }
.hero-copy { position: relative; z-index: 2; }
.eyebrow { display: flex; align-items: center; gap: 10px; margin: 0 0 20px; color: #9fb1cc; font-size: 12px; font-weight: 700; letter-spacing: .16em; }
.eyebrow span { width: 28px; height: 1px; background: linear-gradient(90deg, var(--blue), var(--purple)); }
h1 { margin: 0; font-size: clamp(54px, 6vw, 82px); line-height: 1.07; letter-spacing: -.055em; }
.hero-description { max-width: 510px; margin: 28px 0 34px; color: var(--muted); font-size: 18px; line-height: 1.8; }
.hero-actions { display: flex; gap: 12px; }
.primary-button, .secondary-button { min-width: 205px; min-height: 68px; border-radius: 16px; display: flex; align-items: center; justify-content: center; gap: 12px; border: 1px solid transparent; font: inherit; }
.primary-button { background: linear-gradient(135deg, #6c8cff, #825fff); box-shadow: 0 18px 44px rgba(83, 102, 255, .28); transition: transform .2s ease, box-shadow .2s ease; }
.primary-button:hover { transform: translateY(-2px); box-shadow: 0 22px 52px rgba(83, 102, 255, .38); }
.secondary-button { background: rgba(18, 24, 36, .82); border-color: var(--line); color: #748197; cursor: not-allowed; }
.primary-button span:last-child, .secondary-button span:last-child { display: grid; text-align: left; gap: 3px; }
.primary-button strong, .secondary-button strong { font-size: 15px; }
.primary-button small, .secondary-button small { font-size: 11px; opacity: .72; }
.download-note { color: #718096; font-size: 12px; margin: 14px 0 0; }
.hero-visual { position: relative; transform: perspective(1200px) rotateY(-4deg); }
.hero-visual img { position: relative; z-index: 1; width: 118%; max-width: none; margin-left: -4%; border: 1px solid rgba(126, 148, 191, .24); border-radius: 22px; box-shadow: 0 36px 90px rgba(0, 0, 0, .55); }
.glow { position: absolute; width: 620px; height: 480px; left: 5%; top: 4%; background: radial-gradient(circle, rgba(71, 102, 255, .32), rgba(95, 57, 215, .09) 46%, transparent 72%); filter: blur(20px); }
.hero-insight { position: absolute; z-index: 2; right: -6%; bottom: -22px; width: 330px; padding: 15px 17px; display: flex; align-items: center; gap: 12px; border: 1px solid rgba(139, 157, 255, .34); border-radius: 16px; background: rgba(13, 18, 30, .9); box-shadow: 0 20px 54px rgba(0,0,0,.42); backdrop-filter: blur(18px); }
.hero-insight > span { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 12px; color: #b8c3ff; background: linear-gradient(145deg, rgba(83, 119, 255, .25), rgba(137, 87, 255, .25)); }
.hero-insight div { display: grid; gap: 4px; }
.hero-insight small { color: var(--green); font-size: 11px; }
.hero-insight strong { font-size: 13px; }

.trust-strip { min-height: 82px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); display: flex; justify-content: center; align-items: center; gap: 28px; color: #a8b5c8; font-size: 13px; }
.trust-strip i { width: 4px; height: 4px; border-radius: 50%; background: var(--blue); box-shadow: 0 0 14px var(--blue); }

.assistant-section { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding: 130px 0 0; }
.assistant-heading { align-items: end; }
.assistant-heading > div { max-width: 700px; }
.assistant-heading > div .eyebrow { margin-bottom: 20px; }
.assistant-heading > p { max-width: 360px; margin: 0 0 4px; color: var(--muted); font-size: 15px; line-height: 1.8; }
.assistant-stage { display: grid; grid-template-columns: 1.12fr .88fr; gap: 18px; }
.conversation-card, .plan-card { border: 1px solid var(--line); border-radius: 24px; background: linear-gradient(145deg, rgba(18, 25, 40, .94), rgba(10, 14, 23, .94)); }
.conversation-card { padding: 30px; }
.conversation-head { display: flex; align-items: center; gap: 12px; }
.conversation-head > span { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 13px; color: #b8c3ff; background: rgba(92, 124, 255, .14); }
.conversation-head div { display: grid; gap: 4px; }
.conversation-head b { font-size: 15px; }
.conversation-head small { color: var(--muted); font-size: 11px; }
.conversation-head em { margin-left: auto; padding: 7px 10px; border-radius: 999px; background: rgba(66, 214, 154, .1); color: var(--green); font-size: 11px; font-style: normal; }
.user-message { width: fit-content; max-width: 88%; margin: 34px 0 20px auto; padding: 14px 17px; border-radius: 15px 15px 4px 15px; background: linear-gradient(135deg, #5978ea, #7259d9); font-size: 14px; }
.assistant-message { padding: 20px 22px; border: 1px solid var(--line); border-radius: 4px 16px 16px 16px; background: rgba(255,255,255,.025); }
.assistant-message > p { margin: 0 0 14px; font-weight: 700; }
.assistant-message ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; color: var(--muted); font-size: 13px; }
.assistant-message li { position: relative; padding-left: 16px; line-height: 1.55; }
.assistant-message li::before { content: ""; position: absolute; left: 0; top: .58em; width: 5px; height: 5px; border-radius: 50%; background: var(--blue); }
.assistant-message li b { color: var(--text); }
.model-row { margin-top: 20px; display: flex; flex-wrap: wrap; align-items: center; gap: 8px; color: #7e8ba0; font-size: 11px; }
.model-row span { margin-right: 4px; }
.model-row b { padding: 7px 10px; border: 1px solid var(--line); border-radius: 8px; color: #aab6c9; font-weight: 600; }
.plan-card { padding: 30px; background: radial-gradient(circle at 100% 0, rgba(127, 83, 255, .18), transparent 45%), #101522; }
.plan-status { display: flex; align-items: center; gap: 10px; color: #aebcff; font-size: 13px; font-weight: 700; }
.plan-status .ui-icon { width: 19px; height: 19px; }
.plan-card ol { list-style: none; margin: 27px 0 0; padding: 0; display: grid; }
.plan-card li { min-height: 82px; display: grid; grid-template-columns: 38px 1fr; align-items: center; gap: 14px; border-top: 1px solid var(--line); }
.plan-card li > span { width: 32px; height: 32px; display: grid; place-items: center; border-radius: 10px; color: #aebcff; background: rgba(92, 124, 255, .12); font-size: 12px; }
.plan-card li > span .ui-icon { width: 16px; height: 16px; }
.plan-card li div { display: grid; gap: 5px; }
.plan-card li b { font-size: 14px; }
.plan-card li small { color: var(--muted); font-size: 11px; }
.plan-card li.protected > span { color: var(--green); background: rgba(66,214,154,.1); }
.plan-card > p { margin: 20px 0 0; padding-top: 18px; border-top: 1px solid var(--line); color: #8491a5; font-size: 12px; line-height: 1.65; }
.assistant-capabilities { margin-top: 18px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.assistant-capabilities article { min-height: 218px; padding: 24px; border: 1px solid var(--line); border-radius: 18px; background: rgba(15, 20, 32, .74); }
.assistant-capabilities article > span { width: 40px; height: 40px; display: grid; place-items: center; border-radius: 12px; color: #aebcff; background: rgba(92, 124, 255, .12); }
.assistant-capabilities article .ui-icon { width: 20px; height: 20px; }
.assistant-capabilities h3 { margin: 40px 0 10px; font-size: 17px; }
.assistant-capabilities p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.7; }

.workflow { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding: 130px 0; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 60px; margin-bottom: 56px; }
.section-heading .eyebrow { margin: 0 0 8px; }
.section-heading h2 { margin: 0; max-width: 720px; font-size: clamp(34px, 4vw, 52px); line-height: 1.25; letter-spacing: -.035em; }
.workflow-grid { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(5, 1fr); border: 1px solid var(--line); border-radius: 22px; overflow: hidden; background: linear-gradient(145deg, rgba(20, 27, 42, .9), rgba(11, 15, 24, .9)); }
.workflow-grid li { min-height: 230px; position: relative; padding: 26px; display: flex; flex-direction: column; border-right: 1px solid var(--line); }
.workflow-grid li:last-child { border-right: 0; }
.workflow-grid li:not(:last-child)::after { content: "›"; position: absolute; top: 48px; right: -7px; z-index: 2; color: #6d7b93; background: #111724; }
.workflow-grid li > span { width: 44px; height: 44px; display: grid; place-items: center; border-radius: 13px; color: #b5c0ff; background: rgba(92,124,255,.12); }
.workflow-grid li .ui-icon { width: 21px; height: 21px; }
.workflow-grid b { margin-top: auto; font-size: 19px; }
.workflow-grid small { margin-top: 8px; color: var(--muted); line-height: 1.5; }

.safety { width: min(1120px, calc(100% - 48px)); margin: 0 auto 130px; padding: 58px; display: grid; grid-template-columns: 1.2fr .8fr; gap: 80px; border: 1px solid rgba(85, 117, 255, .28); border-radius: 28px; background: radial-gradient(circle at 0 0, rgba(66, 94, 210, .18), transparent 45%), var(--surface); }
.safety h2 { margin: 0 0 20px; font-size: 40px; letter-spacing: -.035em; }
.safety p { color: var(--muted); line-height: 1.8; }
.safety ul { list-style: none; margin: 0; padding: 0; display: grid; align-content: center; gap: 20px; }
.safety li { padding: 16px 18px; display: flex; align-items: center; gap: 11px; background: rgba(255,255,255,.025); border: 1px solid var(--line); border-radius: 14px; color: #c6d0df; }
.safety li .ui-icon { width: 18px; height: 18px; color: var(--green); }

.final-cta { width: min(1120px, calc(100% - 48px)); margin: 0 auto 110px; padding: 36px 40px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 22px; border-radius: 22px; background: linear-gradient(110deg, #172449, #28205c); border: 1px solid rgba(126, 148, 255, .34); }
.final-cta img { width: 58px; height: 58px; border-radius: 16px; }
.final-cta h2 { margin: 0 0 8px; font-size: 24px; }
.final-cta p { margin: 0; color: #aeb9d2; }
.final-cta > a { padding: 15px 22px; border-radius: 12px; background: white; color: #101528; font-weight: 720; }

footer { width: min(1180px, calc(100% - 48px)); min-height: 100px; margin: 0 auto; border-top: 1px solid var(--line); display: flex; align-items: center; gap: 28px; color: #6f7c90; font-size: 12px; }
footer .brand { color: var(--text); font-size: 15px; }
footer .brand img { width: 26px; height: 26px; }
footer p { flex: 1; }
footer > div:last-child { display: flex; gap: 20px; }
footer a:hover { color: var(--text); }

.legal-content { width: min(760px, calc(100% - 48px)); min-height: calc(100vh - 176px); margin: 0 auto; padding: 90px 0; }
.legal-content h1 { font-size: 54px; }
.legal-date { margin: 18px 0 56px; color: var(--muted); }
.legal-content section { padding: 28px 0; border-top: 1px solid var(--line); }
.legal-content h2 { margin: 0 0 12px; font-size: 21px; }
.legal-content section p { margin: 0; color: var(--muted); line-height: 1.85; }

@media (max-width: 900px) {
  .site-header { height: 66px; }
  nav { display: none; }
  .hero { min-height: auto; padding: 78px 0 72px; grid-template-columns: 1fr; }
  .hero-visual { margin-top: 24px; transform: none; }
  .hero-visual img { width: 100%; margin: 0; }
  .section-heading { align-items: start; flex-direction: column; gap: 18px; }
  .assistant-stage { grid-template-columns: 1fr; }
  .assistant-capabilities { grid-template-columns: repeat(2, 1fr); }
  .workflow-grid { grid-template-columns: 1fr; }
  .workflow-grid li { min-height: 150px; border-right: 0; border-bottom: 1px solid var(--line); }
  .workflow-grid li:last-child { border-bottom: 0; }
  .workflow-grid li:not(:last-child)::after { display: none; }
  .safety { grid-template-columns: 1fr; gap: 34px; padding: 36px; }
}

@media (max-width: 620px) {
  .site-header, .hero, .workflow, .safety, .final-cta, footer, .legal-content { width: min(100% - 32px, 1180px); }
  h1 { font-size: 52px; }
  .hero-description { font-size: 16px; }
  .hero-actions { flex-direction: column; }
  .primary-button, .secondary-button { width: 100%; }
  .trust-strip { padding: 18px; flex-wrap: wrap; gap: 12px; text-align: center; }
  .hero-insight { position: relative; right: auto; bottom: auto; width: calc(100% - 24px); margin: -30px auto 0; }
  .workflow { padding: 92px 0; }
  .assistant-section { width: min(100% - 32px, 1120px); padding-top: 92px; }
  .assistant-capabilities { grid-template-columns: 1fr; }
  .assistant-capabilities article { min-height: 184px; }
  .assistant-capabilities h3 { margin-top: 30px; }
  .section-heading h2, .safety h2 { font-size: 32px; }
  .final-cta { grid-template-columns: auto 1fr; padding: 28px; }
  .final-cta > a { grid-column: 1 / -1; text-align: center; }
  footer { padding: 28px 0; flex-wrap: wrap; }
  footer p { flex-basis: 100%; margin: 0; order: 3; }
}