:root {
  color-scheme: light;
  --background: #faf9fe;
  --surface: #ffffff;
  --surface-low: #f4f3f8;
  --surface-mid: #eeedf3;
  --surface-high: #e3e2e7;
  --text: #1a1b1f;
  --text-muted: #414755;
  --text-soft: #717786;
  --outline: #c1c6d7;
  --outline-strong: #717786;
  --primary: #0058bc;
  --primary-strong: #004493;
  --primary-container: #d8e2ff;
  --secondary: #4c4aca;
  --success: #0d7a4f;
  --radius-sm: 0.25rem;
  --radius: 0.5rem;
  --radius-lg: 1rem;
  --shadow: 0 8px 24px rgba(0, 0, 0, 0.05);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--background);
  color: var(--text);
  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    "Microsoft YaHei",
    sans-serif;
}

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

button {
  color: inherit;
  font: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  height: 64px;
  padding: 0 clamp(1rem, 5vw, 4rem);
  border-bottom: 1px solid var(--outline);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--primary);
  font-size: 1rem;
  font-weight: 700;
}

.brand-mark {
  display: grid;
  width: 1.7rem;
  height: 1.7rem;
  place-items: center;
  border: 1px solid var(--primary);
  border-radius: var(--radius);
  background: var(--primary-container);
  color: var(--primary-strong);
  font-size: 0.88rem;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 3vw, 2.5rem);
  color: var(--text-muted);
  font-size: 0.82rem;
  font-weight: 600;
}

.main-nav a:hover {
  color: var(--primary);
}

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

.language-toggle {
  display: inline-flex;
  gap: 0.2rem;
  border-radius: 999px;
  padding: 0.2rem;
  background: var(--surface-low);
}

.language-toggle button {
  border: 0;
  border-radius: 999px;
  padding: 0.35rem 0.6rem;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.78rem;
  font-weight: 700;
}

.language-toggle button.active {
  background: var(--primary);
  color: #ffffff;
}

.header-cta {
  border-radius: var(--radius);
  padding: 0.55rem 0.9rem;
  background: var(--primary);
  color: #ffffff;
  font-size: 0.86rem;
  font-weight: 700;
}

main {
  width: min(1200px, calc(100% - 2rem));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(400px, 1.1fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center;
  padding: clamp(3.2rem, 7vw, 5rem) 0 clamp(3rem, 6vw, 4.5rem);
}

.hero-copy {
  max-width: 560px;
}

.pill,
.eyebrow,
.card-kicker {
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin: 0 0 1.2rem;
  border-radius: 999px;
  padding: 0.45rem 0.75rem;
  background: var(--primary-container);
  color: var(--primary-strong);
  font-size: 0.72rem;
  font-weight: 700;
}

.pill-dot {
  width: 0.48rem;
  height: 0.48rem;
  border-radius: 999px;
  background: var(--primary);
}

h1,
h2,
h3,
p,
dl {
  margin-top: 0;
}

h1 {
  margin-bottom: 1.25rem;
  font-size: clamp(2rem, 3.4vw, 3rem);
  line-height: 1.16;
  letter-spacing: -0.02em;
}

h2 {
  margin-bottom: 0.85rem;
  font-size: clamp(1.65rem, 2.7vw, 2rem);
  line-height: 1.12;
  letter-spacing: -0.01em;
}

h3 {
  margin-bottom: 0.55rem;
  font-size: 1rem;
  line-height: 1.28;
}

.hero-subtitle,
.section-heading p,
.bento-card p,
.security-section p,
.download-panel p,
.site-footer p,
.site-footer span {
  color: var(--text-muted);
  line-height: 1.65;
}

.hero-subtitle {
  max-width: 520px;
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-bottom: 1.6rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  min-height: 2.75rem;
  border-radius: var(--radius);
  padding: 0.72rem 1.15rem;
  font-size: 0.92rem;
  font-weight: 700;
}

.button.primary {
  background: var(--primary);
  color: #ffffff;
  box-shadow: var(--shadow);
}

.button.secondary {
  border: 1px solid var(--outline);
  background: var(--surface);
  color: var(--primary);
}

.status-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin: 0;
}

.status-grid div {
  min-width: 0;
  border-top: 1px solid var(--outline);
  padding-top: 0.8rem;
}

.status-grid dt {
  color: var(--text-soft);
  font-size: 0.78rem;
}

.status-grid dd {
  margin: 0.25rem 0 0;
  font-weight: 700;
}

.product-frame {
  overflow: hidden;
  border: 1px solid var(--outline);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: 0 32px 80px rgba(0, 88, 188, 0.08);
}

.window-bar {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  min-height: 48px;
  border-bottom: 1px solid var(--outline);
  padding: 0 1.1rem;
  background: var(--surface-low);
}

.window-bar span {
  width: 0.72rem;
  height: 0.72rem;
  border-radius: 999px;
  background: var(--outline);
}

.window-bar strong {
  margin-left: 0.5rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.workspace-preview {
  display: grid;
  grid-template-columns: 120px minmax(210px, 1fr) 208px;
  min-height: 360px;
}

.preview-sidebar {
  border-right: 1px solid var(--outline);
  padding: 1rem;
  background: var(--surface-low);
}

.preview-sidebar p,
.panel-label,
.doc-meta {
  margin-bottom: 0.85rem;
  color: var(--text-soft);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.preview-sidebar button {
  display: block;
  width: 100%;
  margin-bottom: 0.45rem;
  border: 0;
  border-radius: var(--radius);
  padding: 0.65rem 0.7rem;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  text-align: left;
}

.preview-sidebar button.active {
  background: var(--primary-container);
  color: var(--primary-strong);
  font-weight: 700;
}

.document-preview {
  padding: 1rem;
  background:
    linear-gradient(var(--outline) 1px, transparent 1px),
    linear-gradient(90deg, var(--outline) 1px, transparent 1px),
    #ffffff;
  background-size: 32px 32px;
}

.document-preview h2 {
  max-width: 18rem;
  font-size: 1rem;
}

.doc-line {
  display: block;
  height: 0.8rem;
  width: 72%;
  margin-bottom: 0.85rem;
  border-radius: 999px;
  background: #d7dce6;
}

.doc-line.wide {
  width: 86%;
}

.doc-line.medium {
  width: 79%;
}

.doc-line.short {
  width: 58%;
}

.source-highlight {
  width: fit-content;
  max-width: 100%;
  margin-bottom: 0.85rem;
  border: 1px solid #95c7aa;
  border-radius: var(--radius);
  padding: 0.6rem 0.7rem;
  background: #effaf4;
  color: var(--success);
  font-weight: 700;
}

.ai-panel {
  border-left: 1px solid var(--outline);
  padding: 1rem;
  background: #fcfcff;
}

.ai-panel h3 {
  color: var(--text);
  font-size: 1.08rem;
}

.citation {
  margin: 1rem 0;
  border: 1px solid #adc6ff;
  border-radius: var(--radius);
  padding: 0.75rem;
  background: #eef4ff;
  color: var(--primary-strong);
  font-weight: 700;
}

.panel-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.panel-actions button {
  border: 1px solid var(--outline);
  border-radius: var(--radius);
  padding: 0.55rem 0.75rem;
  background: #ffffff;
  cursor: pointer;
  font-weight: 700;
}

.panel-actions button:first-child {
  border-color: var(--primary);
  background: var(--primary);
  color: #ffffff;
}

.section {
  padding: clamp(3rem, 6vw, 5rem) 0;
  border-top: 1px solid var(--outline);
}

.section-heading {
  max-width: 780px;
  margin-bottom: 2rem;
}

.eyebrow,
.card-kicker {
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 700;
}

.step-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.5rem;
}

.step-grid article,
.bento-card {
  border: 1px solid var(--outline);
  border-radius: var(--radius);
  background: var(--surface);
}

.step-grid article {
  min-height: 12rem;
  padding: 1rem;
}

.step-grid span {
  display: inline-block;
  margin-bottom: 2rem;
  color: var(--primary);
  font-weight: 700;
}

.bento-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 1.5rem;
}

.bento-card {
  grid-column: span 4;
  min-height: 13rem;
  padding: 1.2rem;
}

.bento-card.large {
  grid-column: span 8;
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(260px, 1.05fr);
  gap: 1.5rem;
  align-items: stretch;
}

.bento-card.blue {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: var(--primary);
  color: #ffffff;
}

.bento-card.blue p {
  color: rgba(255, 255, 255, 0.86);
}

.citation-demo {
  display: grid;
  align-content: center;
  gap: 0.9rem;
  border-radius: var(--radius);
  padding: 1.2rem;
  background: var(--surface-low);
}

.citation-demo p {
  color: var(--text-soft);
  font-size: 0.8rem;
}

.citation-demo div {
  border-left: 3px solid var(--primary);
  border-radius: var(--radius-sm);
  padding: 0.85rem;
  background: rgba(0, 88, 188, 0.08);
  color: var(--text);
  line-height: 1.55;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 1rem;
}

.chip-row span {
  border-radius: 999px;
  padding: 0.35rem 0.55rem;
  background: rgba(255, 255, 255, 0.15);
  font-size: 0.72rem;
  font-weight: 700;
}

.security-section {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(340px, 1.1fr);
  gap: clamp(2rem, 6vw, 5rem);
}

.security-list {
  display: grid;
  gap: 0.9rem;
}

.security-list div {
  display: grid;
  grid-template-columns: 2.5rem minmax(0, 1fr);
  gap: 0.9rem;
  align-items: start;
  border: 1px solid var(--outline);
  border-radius: var(--radius);
  padding: 1rem;
  background: var(--surface);
}

.security-list span {
  color: var(--primary);
  font-weight: 700;
}

.download-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  margin: 1rem 0 4rem;
  border: 1px solid var(--outline);
  border-radius: var(--radius-lg);
  padding: clamp(1.5rem, 5vw, 3rem);
  background: var(--surface);
}

.download-panel div {
  max-width: 720px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  width: min(1200px, calc(100% - 2rem));
  margin: 0 auto;
  border-top: 1px solid var(--outline);
  padding: 2rem 0 2.4rem;
}

.site-footer strong {
  display: block;
  margin-bottom: 0.6rem;
  color: var(--primary);
  font-size: 1.1rem;
}

.site-footer div:last-child {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.4rem;
}

@media (max-width: 1040px) {
  .hero,
  .security-section {
    grid-template-columns: 1fr;
  }

  .product-frame {
    max-width: 820px;
  }

  .step-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .bento-card,
  .bento-card.large {
    grid-column: span 12;
  }
}

@media (max-width: 760px) {
  .site-header {
    align-items: flex-start;
    height: auto;
    padding-top: 0.8rem;
    padding-bottom: 0.8rem;
  }

  .main-nav,
  .header-cta {
    display: none;
  }

  .hero {
    padding-top: 3rem;
  }

  .status-grid,
  .workspace-preview,
  .step-grid,
  .bento-card.large {
    grid-template-columns: 1fr;
  }

  .preview-sidebar,
  .ai-panel {
    border: 0;
  }

  .preview-sidebar {
    border-bottom: 1px solid var(--outline);
  }

  .ai-panel {
    border-top: 1px solid var(--outline);
  }

  .download-panel,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-footer div:last-child {
    align-items: flex-start;
  }
}

@media (max-width: 520px) {
  main,
  .site-footer {
    width: min(100% - 1rem, 1200px);
  }

  h1 {
    font-size: 2rem;
  }

  .hero-actions .button,
  .download-panel .button {
    width: 100%;
  }
}