:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --surface: rgba(255, 255, 255, .82);
  --surface-solid: #fff;
  --surface-subtle: #eef1f5;
  --text: #111318;
  --muted: #626873;
  --line: rgba(17, 19, 24, .1);
  --line-strong: rgba(17, 19, 24, .2);
  --accent: #2563eb;
  --accent-strong: #1748b7;
  --accent-soft: #e8efff;
  --success: #16734a;
  --shadow-sm: 0 12px 30px rgba(19, 27, 44, .08);
  --shadow-lg: 0 32px 80px rgba(19, 27, 44, .14), 0 8px 24px rgba(19, 27, 44, .07);
  --font-display: "Avenir Next", "SF Pro Display", "PingFang SC", system-ui, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Helvetica Neue", sans-serif;
  --max: 1184px;
  --ease: cubic-bezier(.2, .8, .2, 1);
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #090b0f;
  --surface: rgba(22, 25, 31, .82);
  --surface-solid: #12151b;
  --surface-subtle: #191d24;
  --text: #f5f7fb;
  --muted: #a3a9b3;
  --line: rgba(255, 255, 255, .1);
  --line-strong: rgba(255, 255, 255, .2);
  --accent: #78a7ff;
  --accent-strong: #a7c5ff;
  --accent-soft: #17223a;
  --success: #62d69a;
  --shadow-sm: 0 16px 40px rgba(0, 0, 0, .32);
  --shadow-lg: 0 40px 100px rgba(0, 0, 0, .46), 0 8px 30px rgba(0, 0, 0, .28);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font-body); font-size: 16px; line-height: 1.65; transition: background-color .22s ease, color .22s ease; }
body::before { content: ""; position: fixed; inset: 0; z-index: -1; pointer-events: none; opacity: .62; background: radial-gradient(760px 460px at 72% 6%, rgba(37, 99, 235, .12), transparent 72%); }
button, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }
img { max-width: 100%; }
:focus-visible { outline: 3px solid color-mix(in srgb, var(--accent) 68%, transparent); outline-offset: 3px; }
.container { width: min(calc(100% - 48px), var(--max)); margin-inline: auto; }
.section { padding: 120px 0; scroll-margin-top: 76px; }
.subtle-section { background: color-mix(in srgb, var(--surface-subtle) 62%, transparent); border-block: 1px solid var(--line); }
.section-head { max-width: 760px; margin: 0 0 48px; }
.section-head h2, .download-section h2 { margin: 0 0 16px; font: 700 clamp(34px, 5vw, 56px)/1.08 var(--font-display); letter-spacing: -.045em; }
.section-head > p:last-child { color: var(--muted); font-size: 18px; }
.eyebrow { margin: 0 0 12px; color: var(--accent); font-size: 13px; font-weight: 760; letter-spacing: .1em; text-transform: uppercase; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 100; padding: 9px 14px; border-radius: 9px; background: var(--text); color: var(--bg); transform: translateY(-160%); text-decoration: none; }
.skip-link:focus { transform: translateY(0); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.site-header { position: sticky; top: 0; z-index: 30; border-bottom: 1px solid transparent; backdrop-filter: blur(18px); }
.site-header.scrolled { background: color-mix(in srgb, var(--bg) 84%, transparent); border-color: var(--line); }
.nav-shell { height: 72px; display: flex; align-items: center; gap: 30px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font: 700 18px/1 var(--font-display); letter-spacing: -.02em; }
.brand img { border-radius: 9px; box-shadow: var(--shadow-sm); }
.site-nav { display: flex; align-items: center; gap: 28px; margin-left: auto; }
.site-nav a { color: var(--muted); font-size: 14px; font-weight: 650; text-decoration: none; }
.site-nav a:hover { color: var(--text); }
.nav-actions { display: flex; gap: 8px; }
.theme-toggle, .language-switch, .mobile-menu { height: 40px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); color: var(--text); }
.theme-toggle { position: relative; width: 40px; cursor: pointer; }
.theme-toggle span { position: absolute; inset: 0; display: grid; place-items: center; transition: opacity .18s ease, transform .18s ease; }
.theme-toggle .moon, [data-theme="dark"] .theme-toggle .sun { opacity: 0; transform: scale(.65) rotate(-20deg); }
[data-theme="dark"] .theme-toggle .moon { opacity: 1; transform: scale(1); }
.language-switch { display: grid; place-items: center; min-width: 48px; padding: 0 12px; font-size: 13px; font-weight: 720; text-decoration: none; }
.mobile-menu { display: none; width: 40px; padding: 11px; cursor: pointer; }
.mobile-menu span { display: block; height: 2px; margin: 4px 0; background: currentColor; transition: transform .2s ease; }

.hero { padding: 96px 0 88px; overflow: clip; }
.hero-copy { max-width: 900px; margin: 0 auto 64px; text-align: center; }
.hero-badge, .pill { display: inline-flex; align-items: center; gap: 8px; min-height: 28px; padding: 4px 11px; border-radius: 999px; background: var(--surface); border: 1px solid var(--line); color: var(--muted); font-size: 12px; font-weight: 680; }
.hero-badge::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 5px var(--accent-soft); }
.hero h1 { margin: 24px 0 20px; font: 720 clamp(50px, 8.2vw, 96px)/.98 var(--font-display); letter-spacing: -.065em; }
.hero h1 span { color: var(--muted); font-weight: 520; }
.hero-copy > p:not(.microcopy) { max-width: 700px; margin: 0 auto; color: var(--muted); font-size: clamp(18px, 2vw, 21px); }
.hero-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 0 20px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface-solid); color: var(--text); font-weight: 720; text-decoration: none; cursor: pointer; transition: transform .18s var(--ease), border-color .18s ease, box-shadow .18s ease; }
.button:hover:not(:disabled) { transform: translateY(-2px); border-color: var(--line-strong); box-shadow: var(--shadow-sm); }
.button.primary { background: var(--text); color: var(--bg); border-color: var(--text); }
.button:disabled { cursor: not-allowed; opacity: .48; box-shadow: none; }
.button.compact { min-height: 38px; padding: 0 14px; border-radius: 9px; font-size: 13px; }
.text-button { min-height: 38px; padding: 0 4px; border: 0; background: transparent; color: var(--muted); font-size: 13px; cursor: pointer; text-decoration: underline; text-underline-offset: 4px; }
.microcopy { margin-top: 12px !important; color: var(--muted); font-size: 13px !important; }

.product-stage { overflow: hidden; border: 1px solid var(--line); border-radius: 28px; background: var(--surface); box-shadow: var(--shadow-lg); }
.window-bar { height: 56px; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; padding: 0 20px; border-bottom: 1px solid var(--line); color: var(--muted); font-size: 12px; font-weight: 700; }
.traffic-lights { display: flex; gap: 7px; }
.traffic-lights i { width: 11px; height: 11px; border-radius: 50%; background: #ff5f57; }
.traffic-lights i:nth-child(2) { background: #febc2e; }
.traffic-lights i:nth-child(3) { background: #28c840; }
.window-status { justify-self: end; display: flex; align-items: center; gap: 7px; }
.window-status i { width: 7px; height: 7px; border-radius: 50%; background: var(--success); }
.demo-workspace { display: grid; grid-template-columns: 1.05fr .95fr; min-height: 420px; }
.composer-pane { padding: 42px; border-right: 1px solid var(--line); background: color-mix(in srgb, var(--surface-subtle) 55%, transparent); }
.composer-toolbar { display: flex; justify-content: space-between; margin-bottom: 26px; color: var(--muted); font-size: 13px; }
.composer-pane label { display: block; margin-bottom: 9px; color: var(--muted); font-size: 12px; font-weight: 700; }
.composer-pane textarea { width: 100%; resize: vertical; min-height: 160px; padding: 18px; border: 1px solid var(--line); border-radius: 14px; outline: 0; background: var(--surface-solid); color: var(--text); font-size: 17px; line-height: 1.65; box-shadow: 0 1px 0 rgba(255,255,255,.4) inset; }
.composer-pane textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
.composer-pane > p { margin: 14px 0 0; color: var(--muted); font-size: 12px; }
.translation-panel { padding: 42px; background: var(--surface-solid); }
.panel-heading { display: flex; gap: 12px; align-items: flex-start; }
.panel-dot { width: 10px; height: 10px; margin-top: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 6px var(--accent-soft); }
.panel-heading small, .translation-preview small { display: block; color: var(--muted); font-size: 11px; font-weight: 750; letter-spacing: .08em; text-transform: uppercase; }
.panel-heading h2 { margin: 2px 0 0; font: 700 22px/1.3 var(--font-display); letter-spacing: -.025em; }
.translation-panel > p { min-height: 52px; color: var(--muted); }
.translation-preview { min-height: 112px; padding: 17px; border: 1px solid color-mix(in srgb, var(--accent) 35%, var(--line)); border-radius: 13px; background: var(--accent-soft); }
.translation-preview p { margin: 8px 0 0; color: var(--text); font-weight: 640; }
.demo-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-top: 20px; }

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.feature-card { padding: 18px 18px 28px; border: 1px solid var(--line); border-radius: 22px; background: var(--surface); }
.feature-card > h3, .scenario-card h3, .step h3 { margin: 7px 6px 8px; font: 700 21px/1.25 var(--font-display); letter-spacing: -.025em; }
.feature-card > p:last-child, .scenario-card p, .step p { margin: 0 6px; color: var(--muted); font-size: 14px; }
.card-kicker { margin: 24px 6px 0; color: var(--accent); font-size: 11px; font-weight: 800; letter-spacing: .11em; }
.feature-visual { height: 215px; display: flex; align-items: center; justify-content: center; overflow: hidden; border-radius: 16px; background: var(--surface-subtle); }
.typing-visual { flex-direction: column; gap: 16px; padding: 30px; color: var(--muted); font-size: 14px; }
.typing-visual i { width: 1px; height: 24px; background: var(--accent); animation: blink 1s steps(1) infinite; }
.typing-visual strong { padding: 8px 13px; border-radius: 9px; background: var(--accent-soft); color: var(--accent); }
.selection-visual { position: relative; padding: 30px; color: var(--muted); font-size: 14px; }
.selection-visual mark { background: color-mix(in srgb, var(--accent) 28%, transparent); color: var(--text); }
.selection-visual aside { position: absolute; right: 22px; bottom: 26px; padding: 12px 14px; border: 1px solid var(--line); border-radius: 11px; background: var(--surface-solid); box-shadow: var(--shadow-sm); color: var(--text); }
.selection-visual small { display: block; color: var(--muted); }
.control-visual { flex-direction: column; gap: 10px; padding: 26px; }
.control-visual div { width: 92%; padding: 13px; border: 1px solid var(--line); border-radius: 11px; background: var(--surface-solid); color: var(--muted); font-size: 13px; }
.control-visual div:last-child { transform: translateX(12px); border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); color: var(--accent); }
.control-visual small { display: block; margin-bottom: 3px; color: var(--muted); }

.steps { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); }
.step { position: relative; padding: 34px 34px 8px 0; }
.step:not(:last-child)::after { content: ""; position: absolute; top: 32px; right: 24px; bottom: 0; width: 1px; background: var(--line); }
.step-number { color: var(--accent); font-size: 12px; font-weight: 800; letter-spacing: .1em; }
.step h3, .step p { margin-left: 0; }
.scenario-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.scenario-card { position: relative; min-height: 250px; padding: 32px; overflow: hidden; border: 1px solid var(--line); border-radius: 22px; background: var(--surface); }
.scenario-card::after { content: attr(data-index); position: absolute; top: 22px; right: 24px; color: var(--line-strong); font: 700 12px var(--font-display); }
.scenario-glyph { display: grid; place-items: center; width: 52px; height: 52px; margin-bottom: 52px; border-radius: 15px; background: var(--accent-soft); color: var(--accent); font: 700 18px var(--font-display); }
.scenario-card h3, .scenario-card p { margin-left: 0; }

.customization-grid { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(300px, .7fr); align-items: center; gap: 80px; }
.settings-list { border-top: 1px solid var(--line); }
.setting-row { display: grid; grid-template-columns: .7fr 1.3fr; gap: 24px; padding: 22px 4px; border-bottom: 1px solid var(--line); }
.setting-row strong, .setting-row span { display: block; }
.setting-row span { margin-top: 3px; color: var(--muted); font-size: 12px; }
.setting-row b { align-self: center; color: var(--muted); font-size: 14px; font-weight: 620; }
.privacy-card { padding: 38px; border: 1px solid var(--line); border-radius: 28px; background: var(--surface-solid); box-shadow: var(--shadow-lg); }
.privacy-card > img { display: block; margin-bottom: 30px; border-radius: 18px; }
.privacy-card h3 { margin: 0 0 22px; font: 700 29px/1.2 var(--font-display); }
.privacy-card ul { display: grid; gap: 13px; margin: 0; padding: 0; list-style: none; color: var(--muted); }
.privacy-card li { display: flex; gap: 10px; align-items: center; }
.privacy-card li span { display: grid; place-items: center; width: 21px; height: 21px; border-radius: 50%; background: var(--accent-soft); color: var(--accent); font-size: 11px; font-weight: 800; }

.faq-wrap { max-width: 900px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-item { border-bottom: 1px solid var(--line); }
.faq-item h3 { margin: 0; }
.faq-question { width: 100%; min-height: 78px; display: flex; justify-content: space-between; align-items: center; gap: 24px; padding: 18px 4px; border: 0; background: transparent; color: var(--text); text-align: left; cursor: pointer; font-weight: 720; }
.faq-icon { position: relative; width: 22px; height: 22px; flex: 0 0 auto; }
.faq-icon::before, .faq-icon::after { content: ""; position: absolute; top: 10px; left: 3px; width: 16px; height: 1.5px; background: var(--muted); transition: transform .2s ease; }
.faq-icon::after { transform: rotate(90deg); }
.faq-question[aria-expanded="true"] .faq-icon::after { transform: rotate(0); }
.faq-answer { max-width: 790px; padding: 0 4px 24px; color: var(--muted); }
.faq-answer p { margin: 0; }

.download-section { background: #10141d; color: #f7f9ff; }
.download-grid { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 50px; }
.download-section .pill { background: rgba(120,167,255,.15); border-color: rgba(120,167,255,.22); color: #8bb4ff; }
.download-section h2 { max-width: 780px; margin-top: 20px; }
.download-section p { max-width: 700px; color: #aab1bf; font-size: 18px; }
.download-section img { filter: drop-shadow(0 24px 45px rgba(0, 122, 255, .22)); }
.download-actions { display: flex; align-items: center; gap: 18px; margin-top: 30px; }
.button.inverse { background: #fff; color: #10141d; }
.download-actions span { color: #8e97a8; font-size: 12px; }
.site-footer { padding: 42px 0; border-top: 1px solid var(--line); }
.footer-grid { display: flex; justify-content: space-between; gap: 30px; }
.site-footer p, .footer-note { margin: 12px 0 0; color: var(--muted); font-size: 12px; }
.footer-note { display: grid; align-content: center; gap: 3px; text-align: right; }
.toast { position: fixed; left: 50%; bottom: 28px; z-index: 60; padding: 10px 16px; border-radius: 999px; background: var(--text); color: var(--bg); box-shadow: var(--shadow-lg); opacity: 0; pointer-events: none; transform: translate(-50%, 18px); transition: opacity .2s ease, transform .2s ease; font-size: 13px; font-weight: 700; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }
[hidden] { display: none !important; }

@keyframes blink { 50% { opacity: 0; } }
@media (max-width: 960px) {
  .section { padding: 92px 0; }
  .site-nav { gap: 16px; }
  .hero { padding-top: 72px; }
  .demo-workspace, .customization-grid { grid-template-columns: 1fr; }
  .composer-pane { border-right: 0; border-bottom: 1px solid var(--line); }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-card { display: grid; grid-template-columns: .85fr 1.15fr; column-gap: 28px; align-items: center; }
  .feature-visual { grid-row: 1 / span 3; height: 240px; }
  .feature-card .card-kicker { margin-top: 0; }
  .customization-grid { gap: 50px; }
  .privacy-card { max-width: 560px; }
}

@media (max-width: 720px) {
  .container { width: min(calc(100% - 32px), var(--max)); }
  .section { padding: 76px 0; }
  .nav-shell { position: relative; gap: 10px; }
  .mobile-menu { display: block; margin-left: auto; }
  .site-nav { position: absolute; top: 62px; left: 0; right: 0; display: none; flex-direction: column; align-items: stretch; gap: 0; padding: 10px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface-solid); box-shadow: var(--shadow-lg); }
  .site-nav.open { display: flex; }
  .site-nav a { padding: 11px 12px; border-radius: 8px; }
  .brand span { display: none; }
  .hero { padding: 54px 0 64px; }
  .hero-copy { margin-bottom: 42px; }
  .hero h1 { font-size: clamp(44px, 13vw, 64px); }
  .hero-actions .button { width: 100%; }
  .window-bar { grid-template-columns: 1fr auto; }
  .window-bar > span:nth-child(2) { display: none; }
  .composer-pane, .translation-panel { padding: 25px 20px; }
  .composer-pane textarea { min-height: 140px; }
  .feature-card { display: block; }
  .feature-visual { height: 205px; margin-bottom: 24px; }
  .feature-card .card-kicker { margin-top: 0; }
  .steps { grid-template-columns: 1fr; }
  .step { padding: 28px 0; border-bottom: 1px solid var(--line); }
  .step:not(:last-child)::after { display: none; }
  .scenario-grid { grid-template-columns: 1fr; }
  .scenario-card { min-height: 225px; }
  .setting-row { grid-template-columns: 1fr; gap: 8px; }
  .privacy-card { padding: 28px; }
  .download-grid { grid-template-columns: 1fr; }
  .download-grid > img { order: -1; width: 96px; }
  .download-actions { align-items: flex-start; flex-direction: column; }
  .footer-grid { flex-direction: column; }
  .footer-note { text-align: left; }
}

@media (max-width: 420px) {
  .hero h1 { letter-spacing: -.055em; }
  .product-stage { border-radius: 20px; }
  .demo-actions .button { width: 100%; }
  .scenario-card { padding: 26px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}