:root {
  color-scheme: light dark;
  --bg: #F5F4ED;
  --chrome: #F0EEE6;
  --surface: #FAF8F2;
  --border: #E3E0D6;
  --border-strong: #C9C5B8;
  --text: #1F1E1D;
  --muted: #5C5A54;
  --claude: #A8471F;
  --codex: #087459;
  --kimi: #1663C6;
  --focus: #276C8D;
  --font: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei UI", "PingFang SC", "Noto Sans CJK SC", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1F1E1D;
    --chrome: #262624;
    --surface: #2A2926;
    --border: #3A3936;
    --border-strong: #55534E;
    --text: #F2F0EA;
    --muted: #A8A59D;
    --claude: #EDA88E;
    --codex: #2BC49C;
    --kimi: #5AA9FF;
    --focus: #4FA8D0;
  }
}

* { box-sizing: border-box; }
html { scroll-padding-top: 28px; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font); font-size: 16px; line-height: 1.7; -webkit-font-smoothing: antialiased; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 5px; }
a:hover { text-decoration-color: var(--muted); }
button { font: inherit; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 5px; }
::selection { background: var(--text); color: var(--bg); }
h1, h2, h3, p, figure { margin: 0; }
h1, h2, h3 { line-height: 1.16; text-wrap: balance; }
h1 { font-size: clamp(40px, 4.75vw, 68px); font-weight: 650; letter-spacing: -0.055em; }
h1 span { display: block; }
h2 { font-size: clamp(28px, 3.15vw, 42px); font-weight: 620; letter-spacing: -0.045em; }
h3 { font-size: 20px; font-weight: 620; letter-spacing: -0.025em; }
p { color: var(--muted); max-width: 68ch; }
picture, img { display: block; }
img { max-width: 100%; height: auto; }
.wrap { width: min(1200px, calc(100% - 96px)); margin-inline: auto; }
.section { padding-block: 88px; }
.small { font-size: 14px; line-height: 1.7; }
.skip-link { position: fixed; z-index: 2; top: 12px; left: 16px; padding: 8px 16px; background: var(--text); color: var(--bg); transform: translateY(-200%); }
.skip-link:focus { transform: none; }

.site-header { display: flex; min-height: 100px; align-items: center; gap: 32px; }
.brand { display: inline-flex; align-items: center; gap: 11px; text-decoration: none; font-size: 23px; font-weight: 700; letter-spacing: -0.04em; }
.brand img { flex-shrink: 0; }
.navigation { display: flex; align-items: center; gap: 28px; margin-left: auto; font-size: 14px; }
.navigation a { text-decoration: none; }
.navigation a:hover { text-decoration: underline; }
.language-switch { display: flex; flex-shrink: 0; align-items: center; gap: 2px; padding: 3px; border: 1px solid var(--border); border-radius: 8px; }
.language-switch button { min-width: 44px; min-height: 36px; border: 0; border-radius: 5px; padding: 5px 9px; color: var(--muted); background: transparent; cursor: pointer; font-size: 13px; }
.language-switch button[aria-pressed="true"] { background: var(--text); color: var(--bg); }

.hero { display: grid; grid-template-columns: 1.25fr 1fr; align-items: center; column-gap: 36px; padding-top: 74px; }
.hero-description { max-width: 48ch; margin-top: 28px; font-size: 18px; line-height: 1.7; }
.actions { display: flex; align-items: center; flex-wrap: wrap; gap: 28px; margin-top: 32px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 50px; padding: 11px 22px; text-align: center; text-decoration: none; font-size: 15px; font-weight: 600; border: 1px solid var(--text); border-radius: 8px; }
.button-primary { background: var(--text); color: var(--bg); }
.button-primary:hover { background: var(--surface); color: var(--text); }
.text-link { font-size: 15px; font-weight: 550; }
/* Crop only the illustration from the supplied banner, leaving the headline as real text. */
.hero-art { position: relative; aspect-ratio: 1.5; overflow: hidden; }
.hero-art picture { position: absolute; inset: 0; }
.hero-art img { position: absolute; width: 270%; max-width: none; left: -150%; top: -45%; }
.agent-list { grid-column: 1 / -1; display: flex; flex-wrap: wrap; gap: 18px 38px; list-style: none; margin: 64px 0 0; padding: 23px 0; border-block: 1px solid var(--border); font-size: 14px; }
.agent-list li { display: flex; align-items: center; gap: 10px; }
.agent-list li span { width: 8px; height: 8px; border-radius: 50%; background: currentColor; }
.claude { color: var(--claude); }
.codex { color: var(--codex); }
.kimi { color: var(--kimi); }

.section-intro { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: start; margin-bottom: 40px; }
.section-intro p { max-width: 48ch; padding-top: 4px; }
.feature-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 40px; }
.feature-grid article { padding-top: 22px; border-top: 1px solid var(--border-strong); }
.feature-grid p { margin-top: 16px; font-size: 15px; }
.desktop-section { padding-top: 12px; }
.screenshot img { width: 100%; }
.desktop-shot picture { border: 1px solid var(--border); border-radius: 12px; overflow: hidden; background: var(--chrome); }
figcaption { max-width: 78ch; margin: 16px auto 0; text-align: center; font-size: 13px; line-height: 1.65; color: var(--muted); }

.phone-section { background: var(--chrome); }
.phone-layout { display: grid; grid-template-columns: 0.85fr 1.6fr; align-items: center; gap: 56px; }
.phone-copy h2 { max-width: 12ch; }
.phone-copy p { margin-top: 24px; }
.phone-copy .small { margin-top: 18px; }
.mobile-shot { min-width: 0; }
.demo-note { margin-top: 28px; text-align: center; font-size: 13px; }

.how-diagram { margin-inline: -24px; }
.how-diagram img { width: 100%; }
.how-text { margin-top: 28px; max-width: 82ch; font-size: 15px; }
.security-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 72px; padding: 48px; background: var(--surface); border: 1px solid var(--border-strong); border-radius: 16px; }
.security-panel h2 { font-size: 30px; }
.security-statement { margin-top: 20px; color: var(--text); font-weight: 600; }
.security-panel p + p { margin-top: 12px; }
.security-panel .text-link { display: inline-block; margin-top: 24px; }
.boundaries { list-style: none; margin: 0; padding: 0; }
.boundaries li + li { margin-top: 22px; }
.boundaries strong, .boundaries span { display: block; }
.boundaries strong { font-size: 15px; font-weight: 600; }
.boundaries span { margin-top: 4px; color: var(--muted); font-size: 14px; }

.start-section { display: flex; align-items: center; justify-content: space-between; gap: 40px; padding-block: 104px; }
.start-section p { margin-top: 18px; }
.start-section .small { max-width: 65ch; margin-top: 10px; }
.start-section .button { flex-shrink: 0; }
.site-footer { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 24px; min-height: 104px; padding-block: 24px; border-top: 1px solid var(--border); }
.site-footer .brand { font-size: 18px; gap: 9px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 12px 24px; color: var(--muted); font-size: 13px; }
.footer-links a { text-decoration: none; }
.footer-links a:hover { text-decoration: underline; }

:lang(zh-CN) h1 { font-size: clamp(36px, 4.25vw, 60px); letter-spacing: -0.045em; line-height: 1.32; }
:lang(zh-CN) h2 { letter-spacing: -0.025em; line-height: 1.3; }
:lang(zh-CN) .phone-copy h2 { max-width: 9em; }

@media (min-width: 1600px) {
  .hero { padding-top: 104px; }
}

@media (max-width: 1000px) {
  .wrap { width: calc(100% - 64px); }
  .hero { grid-template-columns: 1.4fr 1fr; column-gap: 12px; }
  h1 { font-size: clamp(38px, 5vw, 52px); }
  .hero-description { font-size: 16px; }
  .feature-grid { gap: 26px; }
  .phone-layout { grid-template-columns: 1fr 1.4fr; gap: 24px; }
  .security-panel { padding: 32px; gap: 36px; }
  .start-section { flex-direction: column; align-items: flex-start; gap: 28px; }
}

@media (max-width: 680px) {
  .wrap { width: calc(100% - 32px); }
  .site-header { min-height: 80px; justify-content: space-between; gap: 12px; }
  .site-header .brand { font-size: 22px; }
  .navigation { display: none; }
  .language-switch button { min-height: 38px; }
  .section { padding-block: 56px; }
  .hero { grid-template-columns: minmax(0, 1fr); padding-top: 38px; }
  h1 { font-size: clamp(36px, 8.6vw, 56px); }
  .hero-description { max-width: 44ch; margin-top: 22px; }
  .actions { gap: 24px; margin-top: 26px; }
  .hero-art { width: min(100%, 420px); margin: 28px auto 0; aspect-ratio: 1.7; }
  .hero-art img { top: -51%; }
  .agent-list { gap: 12px 24px; margin-top: 22px; padding-block: 19px; font-size: 13px; }
  .agent-list li { gap: 7px; }
  .section-intro { grid-template-columns: minmax(0, 1fr); gap: 16px; margin-bottom: 28px; }
  .feature-grid { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .feature-grid article { padding-top: 20px; }
  .feature-grid p { margin-top: 12px; }
  .desktop-section { padding-top: 0; }
  .desktop-shot picture { border-radius: 6px; }
  .phone-layout { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .phone-copy h2 { max-width: 18ch; }
  .phone-copy p { margin-top: 18px; }
  .demo-note { margin-top: 24px; }
  .how-diagram { margin-inline: 0; }
  .how-text { margin-top: 24px; }
  .security-panel { grid-template-columns: minmax(0, 1fr); padding: 28px 22px; gap: 30px; border-radius: 12px; }
  .security-panel h2 { font-size: 28px; }
  .boundaries { border-top: 1px solid var(--border); padding-top: 24px; }
  .site-footer { align-items: flex-start; padding-block: 26px; }
  .footer-links { width: 100%; gap: 16px 20px; }
  :lang(zh-CN) h1 { font-size: clamp(32px, 7.8vw, 50px); }
}

@media (prefers-reduced-motion: no-preference) {
  .button { transition: background-color 140ms ease, color 140ms ease; }
}