:root {
  --ink: #1a2332;
  --ink-2: #2c3a4d;
  --muted: #6b7c90;
  --muted-2: #8a9aab;
  --line: rgba(26, 35, 50, 0.08);
  --line-strong: rgba(26, 35, 50, 0.14);
  --paper: #f4f8fc;
  --paper-2: #e8f0f8;
  --white: #ffffff;
  --panel: rgba(255, 255, 255, 0.72);
  --accent: #4d6bfe;
  --accent-deep: #3a56e8;
  --accent-soft: rgba(77, 107, 254, 0.12);
  --accent-glow: rgba(77, 107, 254, 0.28);
  --sky: #a8c8f0;
  --sky-2: #c5d9f5;
  --lavender: #d4d8f0;
  --shadow: 0 20px 50px rgba(60, 90, 140, 0.12);
  --shadow-sm: 0 8px 28px rgba(60, 90, 140, 0.08);
  --radius: 20px;
  --radius-sm: 12px;
  --header-h: 64px;
  --max: 1180px;
  --composer-max: 760px;
  --font-display: "Sora", "Noto Sans SC", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--font-body);
  background: var(--paper);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  padding: 0.1em 0.35em;
  border-radius: 6px;
  background: rgba(26, 35, 50, 0.06);
}

button {
  font: inherit;
}

::selection {
  background: rgba(77, 107, 254, 0.22);
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--ink);
  color: #fff;
  padding: 0.6rem 1rem;
  z-index: 100;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.bg-mesh {
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  overflow: hidden;
  background: var(--paper);
}

.bg-mesh::before,
.bg-mesh::after {
  content: none;
  display: none;
}

.container {
  width: min(100% - 2.5rem, var(--max));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  border-bottom: 1px solid transparent;
  background: transparent;
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  background: rgba(244, 248, 252, 0.78);
  backdrop-filter: blur(16px) saturate(1.2);
}

.site-header .inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: min(100% - 2rem, 1120px);
  margin-inline: auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
}

.brand img {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 0 0 1px var(--line);
}

.brand-text {
  display: flex;
  align-items: baseline;
  gap: 0.45rem;
  line-height: 1;
}

.brand-zh {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.brand-en {
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: lowercase;
  color: var(--muted);
}

.nav {
  display: none;
  align-items: center;
  gap: 0.15rem;
}

.nav a {
  padding: 0.45rem 0.8rem;
  border-radius: 999px;
  color: var(--ink-2);
  font-size: 0.92rem;
  transition: background 0.2s ease, color 0.2s ease;
}

.nav a:hover,
.nav a[aria-current="page"] {
  background: rgba(26, 35, 50, 0.05);
  color: var(--ink);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.header-link {
  color: var(--ink-2);
  font-size: 0.92rem;
  font-weight: 500;
  padding: 0.35rem 0.25rem;
  transition: color 0.2s ease;
}

.header-link:hover {
  color: var(--accent-deep);
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  padding: 3px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line-strong);
  box-shadow: var(--shadow-sm);
}

.lang-switch button {
  border: 0;
  background: transparent;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.35rem 0.7rem;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.lang-switch button[aria-pressed="true"] {
  background: rgba(26, 35, 50, 0.08);
  color: var(--ink);
}

.menu-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.7);
  cursor: pointer;
}

.menu-btn span,
.menu-btn span::before,
.menu-btn span::after {
  display: block;
  width: 16px;
  height: 1.5px;
  background: var(--ink);
  position: relative;
}

.menu-btn span::before,
.menu-btn span::after {
  content: "";
  position: absolute;
  left: 0;
}

.menu-btn span::before {
  top: -5px;
}

.menu-btn span::after {
  top: 5px;
}

.mobile-nav {
  display: none;
  border-bottom: 1px solid var(--line);
  background: rgba(247, 250, 253, 0.96);
  backdrop-filter: blur(12px);
}

.mobile-nav.open {
  display: block;
}

.mobile-nav a {
  display: block;
  padding: 0.95rem 1.25rem;
  border-top: 1px solid var(--line);
  color: var(--ink-2);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  min-height: 48px;
  padding: 0 1.25rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 500;
  letter-spacing: 0.01em;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
  cursor: pointer;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--ink);
  color: #fff;
  border-color: var(--ink);
}

.btn-primary:hover {
  background: var(--accent-deep);
  border-color: var(--accent-deep);
  box-shadow: 0 10px 28px var(--accent-glow);
}

.btn-accent {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  font-weight: 600;
}

.btn-accent:hover {
  background: var(--accent-deep);
  border-color: var(--accent-deep);
  box-shadow: 0 10px 28px var(--accent-glow);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.55);
  border-color: var(--line-strong);
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent-deep);
  background: var(--accent-soft);
}

.btn-sm {
  min-height: 40px;
  padding: 0 1rem;
  font-size: 0.9rem;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 1rem;
  color: var(--accent-deep);
  font-size: 0.86rem;
  font-weight: 500;
  letter-spacing: 0.08em;
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 2px;
  background: var(--accent);
}

h1,
h2,
h3,
h4 {
  font-family: var(--font-display);
  line-height: 1.15;
  letter-spacing: 0.02em;
  margin: 0;
}

.lead {
  margin: 1rem 0 0;
  color: var(--ink-2);
  font-size: clamp(1.02rem, 1.6vw, 1.15rem);
  max-width: 40rem;
}

.section {
  padding: clamp(4rem, 9vh, 7rem) 0;
}

.section-head {
  max-width: 40rem;
  margin-bottom: clamp(2rem, 4vw, 3rem);
}

.section-head h2 {
  font-size: clamp(1.85rem, 4vw, 2.75rem);
  font-weight: 700;
}

.section-head p {
  margin: 0.9rem 0 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 3.5rem 0 2.5rem;
  background: rgba(255, 255, 255, 0.4);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 2rem;
}

.footer-grid-simple {
  grid-template-columns: 1.6fr 1fr 1fr;
}

.footer-brand {
  display: flex;
  gap: 0.85rem;
  align-items: flex-start;
}

.footer-brand img {
  width: 40px;
  height: 40px;
  border-radius: 9px;
  border: 1px solid var(--line);
  background: #fff;
}

.footer-brand strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.05rem;
}

.footer-brand p {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.92rem;
  max-width: 22rem;
}

.footer-col h4 {
  margin: 0 0 0.9rem;
  font-size: 0.82rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 600;
}

.footer-col a {
  display: block;
  color: var(--ink-2);
  padding: 0.28rem 0;
  font-size: 0.95rem;
}

.footer-col a:hover {
  color: var(--accent-deep);
}

.footer-bottom {
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  color: var(--muted);
  font-size: 0.88rem;
}

.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.75s ease, transform 0.75s ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

@media (min-width: 920px) {
  .nav {
    display: flex;
  }

  .menu-btn {
    display: none;
  }

  .mobile-nav {
    display: none !important;
  }
}

@media (max-width: 919px) {
  .footer-grid,
  .footer-grid-simple {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .container {
    width: min(100% - 1.5rem, var(--max));
  }

  .footer-grid,
  .footer-grid-simple {
    grid-template-columns: 1fr;
  }

  .brand-en {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal,
  .bg-mesh::after,
  .hero-announce,
  .composer-shell,
  .hero-cta,
  .phone,
  .lever-group,
  .load,
  .effort,
  .wave span {
    animation: none !important;
    transition: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}