:root {
  color-scheme: light;

  --neutral-050: #f7f7f8;
  --neutral-100: #eeeeef;
  --neutral-200: #d8d9dc;
  --neutral-300: #b8bbc1;
  --neutral-500: #737780;
  --neutral-600: #5b606a;
  --neutral-700: #3d424c;
  --neutral-800: #2b3038;
  --neutral-875: #20242b;
  --neutral-900: #171b21;
  --neutral-950: #0d1015;
  --blue-400: #7aa7ff;
  --blue-600: #2458d6;
  --green-400: #5fd18b;
  --green-600: #168a45;
  --amber-400: #f0c15a;
  --amber-600: #b77900;
  --white: #ffffff;

  --color-background-default: var(--neutral-050);
  --color-background-elevated: var(--white);
  --color-surface-default: var(--white);
  --color-surface-muted: var(--neutral-100);
  --color-border-subtle: var(--neutral-200);
  --color-border-default: var(--neutral-300);
  --color-border-strong: var(--neutral-600);
  --color-text-primary: var(--neutral-950);
  --color-text-secondary: var(--neutral-700);
  --color-text-muted: var(--neutral-500);
  --color-text-inverse: var(--white);
  --color-primary-default: var(--blue-600);
  --color-primary-hover: var(--blue-600);
  --color-primary-pressed: var(--blue-600);
  --color-success-default: var(--green-600);
  --color-warning-default: var(--amber-600);

  --font-display-lg: 56px;
  --font-heading-lg: 32px;
  --font-heading-md: 24px;
  --font-heading-sm: 20px;
  --font-body-lg: 18px;
  --font-body-md: 16px;
  --font-body-sm: 14px;
  --font-caption: 12px;

  --space-4: 4px;
  --space-8: 8px;
  --space-12: 12px;
  --space-16: 16px;
  --space-24: 24px;
  --space-32: 32px;
  --space-48: 48px;
  --space-64: 64px;

  --radius-button: 10px;
  --radius-card: 14px;
  --border-default: 1px;
  --border-strong: 2px;
  --container-max: 1200px;
  --motion-fast: 120ms;
  --motion-default: 180ms;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  overflow-x: clip;
  background: var(--color-background-default);
  color: var(--color-text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: var(--font-body-md);
  line-height: 1.5;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

button {
  font: inherit;
}

:focus-visible {
  outline: 3px solid var(--color-primary-default);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: var(--space-12);
  left: var(--space-12);
  z-index: 100;
  padding: var(--space-12) var(--space-16);
  border-radius: var(--radius-button);
  background: var(--color-text-primary);
  color: var(--color-text-inverse);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: var(--border-default) solid var(--color-border-subtle);
  background: var(--color-background-elevated);
}

.header-inner,
.hero,
.content-section,
.final-cta,
.footer-grid,
.footer-bottom {
  width: min(calc(100% - 64px), var(--container-max));
  margin-inline: auto;
}

.header-inner {
  min-height: 72px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: var(--space-24);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: var(--font-body-sm);
  font-weight: 700;
  letter-spacing: .08em;
}

.brand img {
  flex: 0 0 24px;
}

.desktop-nav {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
}

.desktop-nav a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  padding-inline: var(--space-12);
  color: var(--color-text-secondary);
  font-size: var(--font-body-sm);
  border-radius: var(--radius-button);
  transition: color var(--motion-fast) ease-out, background var(--motion-fast) ease-out;
}

.desktop-nav a:hover {
  color: var(--color-text-primary);
  background: var(--color-surface-muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.language-switch,
.mobile-menu summary {
  min-height: 40px;
  border: var(--border-default) solid var(--color-border-default);
  border-radius: var(--radius-button);
  background: var(--color-surface-default);
  color: var(--color-text-secondary);
  padding-inline: var(--space-12);
  font-size: var(--font-body-sm);
}

.language-switch[disabled] {
  cursor: default;
  opacity: .78;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-12) 20px;
  border: var(--border-strong) solid var(--color-primary-default);
  border-radius: var(--radius-button);
  background: var(--color-primary-default);
  color: var(--color-text-inverse);
  font-weight: 600;
  line-height: 1.2;
  transition: background var(--motion-fast) ease-out, border-color var(--motion-fast) ease-out, transform var(--motion-fast) ease-out;
}

.button:hover {
  border-color: var(--color-primary-hover);
  background: var(--color-primary-hover);
}

.button:active {
  border-color: var(--color-primary-pressed);
  background: var(--color-primary-pressed);
  transform: translateY(1px);
}

.button-small {
  min-height: 40px;
  padding: var(--space-8) var(--space-16);
  font-size: var(--font-body-sm);
}

.button-secondary {
  background: transparent;
  color: var(--color-primary-default);
}

.button-secondary:hover {
  color: var(--color-text-inverse);
}

.mobile-menu {
  display: none;
}

.mobile-menu summary {
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  list-style: none;
}

.mobile-menu summary::-webkit-details-marker {
  display: none;
}

.hero {
  min-height: calc(84svh - 72px);
  padding-block: var(--space-64);
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(320px, 5fr);
  gap: var(--space-64);
  align-items: center;
}

.hero-copy {
  max-width: 720px;
}

.eyebrow,
.section-label,
.meta-label,
.solution-kicker {
  margin: 0;
  color: var(--color-text-muted);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: var(--font-caption);
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 760px;
  margin: var(--space-16) 0 var(--space-24);
  font-size: var(--font-display-lg);
  line-height: 64px;
  letter-spacing: -.04em;
}

.hero-subtitle {
  max-width: 680px;
  margin: 0;
  color: var(--color-text-secondary);
  font-size: var(--font-body-lg);
  line-height: 28px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-12);
  margin-top: var(--space-32);
}

.north-star {
  max-width: 560px;
  margin-top: var(--space-32);
  display: flex;
  align-items: center;
  gap: var(--space-16);
  padding: var(--space-16);
  border-left: var(--border-strong) solid var(--color-primary-default);
  background: var(--color-surface-muted);
}

.north-star p:last-child {
  margin: var(--space-4) 0 0;
  font-weight: 600;
}

.north-star-mark {
  width: 32px;
  height: 32px;
  flex: 0 0 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--color-primary-default);
  color: var(--color-text-inverse);
  font-weight: 700;
}

.workflow-panel {
  margin: 0;
  overflow: hidden;
  border: var(--border-default) solid var(--color-border-default);
  border-radius: var(--radius-card);
  background: var(--color-surface-default);
}

.workflow-panel figcaption {
  display: grid;
  gap: var(--space-8);
  padding: var(--space-24);
  border-bottom: var(--border-default) solid var(--color-border-subtle);
}

.workflow-panel ol {
  margin: 0;
  padding: 0 var(--space-24);
  list-style: none;
}

.workflow-panel li {
  min-height: 76px;
  display: grid;
  grid-template-columns: 40px 1fr;
  align-content: center;
  column-gap: var(--space-12);
  border-bottom: var(--border-default) solid var(--color-border-subtle);
}

.workflow-panel li > span {
  grid-row: 1 / 3;
  align-self: center;
  color: var(--color-primary-default);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: var(--font-caption);
}

.workflow-panel li small {
  color: var(--color-text-muted);
  font-size: var(--font-body-sm);
}

.panel-boundary {
  margin: 0;
  padding: var(--space-16) var(--space-24);
  color: var(--color-text-secondary);
  background: var(--color-surface-muted);
  font-size: var(--font-body-sm);
}

.content-section {
  padding-block: 96px;
  border-top: var(--border-default) solid var(--color-border-subtle);
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(140px, 3fr) minmax(0, 5fr) minmax(240px, 4fr);
  gap: var(--space-32);
  align-items: start;
  margin-bottom: var(--space-48);
}

.section-heading h2,
.why-intro h2,
.final-cta h2 {
  margin: 0;
  font-size: var(--font-heading-lg);
  line-height: 40px;
  letter-spacing: -.025em;
}

.section-heading > p:last-child,
.why-intro > p:last-child {
  margin: 0;
  color: var(--color-text-secondary);
}

.problem-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-16);
}

.problem-card,
.solution-card,
.evidence-card {
  border: var(--border-default) solid var(--color-border-default);
  border-radius: var(--radius-card);
  background: var(--color-surface-default);
  padding: var(--space-24);
}

.problem-card > span,
.step-index,
.principle-list > li > span,
.evidence-topline > span:last-child {
  color: var(--color-text-muted);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: var(--font-caption);
}

.problem-card h3,
.solution-card h3,
.evidence-card h3,
.workflow-step h3,
.principle-list h3 {
  margin: var(--space-16) 0 var(--space-8);
  font-size: var(--font-heading-sm);
  line-height: 28px;
}

.problem-card p,
.solution-card > p:last-of-type,
.workflow-step p,
.principle-list p {
  margin: 0;
  color: var(--color-text-secondary);
}

.section-note {
  margin: var(--space-24) 0 0;
  color: var(--color-text-muted);
  font-size: var(--font-body-sm);
}

.workflow-section {
  width: 100%;
  max-width: none;
  padding-inline: max(32px, calc((100% - var(--container-max)) / 2));
  background: var(--color-surface-muted);
}

.workflow-section .section-heading,
.workflow-grid {
  max-width: var(--container-max);
  margin-inline: auto;
}

.workflow-grid {
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-16);
  list-style: none;
}

.workflow-step {
  min-height: 180px;
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: var(--space-16);
  padding: var(--space-24);
  border-top: var(--border-strong) solid var(--color-primary-default);
  background: var(--color-background-elevated);
}

.workflow-step h3 {
  margin-top: 0;
}

.solutions-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--space-16);
}

.solution-card {
  min-height: 280px;
  grid-column: span 5;
  display: flex;
  flex-direction: column;
}

.solution-card:nth-child(3) {
  grid-column: span 7;
}

.solution-enterprise {
  grid-column: span 7;
  border-width: var(--border-strong);
  border-color: var(--color-primary-default);
}

.solution-muted {
  grid-column: span 5;
  border-style: dashed;
  background: transparent;
}

.status-badge {
  min-height: 28px;
  width: fit-content;
  display: inline-flex;
  align-items: center;
  padding: var(--space-4) var(--space-8);
  border: var(--border-default) solid currentColor;
  border-radius: 999px;
  font-size: var(--font-caption);
  font-weight: 600;
}

.status-primary { color: var(--color-primary-default); }
.status-warning { color: var(--color-warning-default); }
.status-success { color: var(--color-success-default); }
.status-neutral { color: var(--color-text-secondary); }
.status-muted { color: var(--color-text-muted); }

.solution-kicker {
  margin-top: var(--space-32);
}

.solution-card h3 {
  margin-top: var(--space-8);
  font-size: var(--font-heading-md);
  line-height: 32px;
}

.text-link {
  width: fit-content;
  margin-top: auto;
  padding-top: var(--space-24);
  color: var(--color-primary-default);
  font-weight: 600;
}

.text-link:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.why-section {
  display: grid;
  grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
  gap: var(--space-64);
}

.why-intro h2 {
  margin: var(--space-16) 0;
}

.principle-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: var(--border-default) solid var(--color-border-default);
}

.principle-list li {
  display: grid;
  grid-template-columns: 40px 1fr;
  gap: var(--space-16);
  padding-block: var(--space-24);
  border-bottom: var(--border-default) solid var(--color-border-default);
}

.principle-list h3 {
  margin: 0 0 var(--space-4);
}

.evidence-section {
  width: 100%;
  max-width: none;
  padding-inline: max(32px, calc((100% - var(--container-max)) / 2));
  background: var(--color-surface-muted);
}

.evidence-section .section-heading,
.evidence-grid,
.boundary-note {
  max-width: var(--container-max);
  margin-inline: auto;
}

.evidence-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-16);
}

.evidence-topline {
  display: flex;
  justify-content: space-between;
  gap: var(--space-16);
  align-items: center;
}

.evidence-card h3 {
  margin-block: var(--space-24);
  font-size: var(--font-heading-md);
  line-height: 32px;
}

.evidence-card dl {
  margin: 0;
}

.evidence-card dl > div {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: var(--space-16);
  padding-block: var(--space-12);
  border-top: var(--border-default) solid var(--color-border-subtle);
}

.evidence-card dt {
  color: var(--color-text-muted);
  font-size: var(--font-body-sm);
}

.evidence-card dd {
  margin: 0;
  color: var(--color-text-secondary);
}

.boundary-note {
  margin-top: var(--space-24);
  padding: var(--space-16) var(--space-24);
  display: flex;
  gap: var(--space-24);
  border-left: var(--border-strong) solid var(--color-warning-default);
  background: var(--color-background-elevated);
}

.boundary-note p {
  margin: 0;
  color: var(--color-text-secondary);
}

.final-cta {
  margin-block: 112px;
  padding: var(--space-48);
  display: grid;
  grid-template-columns: minmax(0, 8fr) minmax(260px, 4fr);
  gap: var(--space-48);
  align-items: center;
  border-radius: var(--radius-card);
  background: var(--color-text-primary);
  color: var(--color-text-inverse);
}

.final-cta .section-label {
  color: var(--blue-400);
}

.final-cta h2 {
  margin-block: var(--space-12);
}

.final-cta p {
  color: var(--neutral-300);
}

.final-cta ul {
  margin: var(--space-24) 0 0;
  padding-left: var(--space-24);
  color: var(--neutral-300);
}

.cta-action {
  display: grid;
  gap: var(--space-12);
}

.button-inverse {
  background: var(--blue-400);
  border-color: var(--blue-400);
  color: var(--neutral-950);
}

.cta-action p {
  margin: 0;
  font-size: var(--font-caption);
}

.site-footer {
  border-top: var(--border-default) solid var(--color-border-default);
  background: var(--color-surface-muted);
}

.footer-grid {
  padding-block: var(--space-64);
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--space-48);
}

.footer-statement {
  max-width: 360px;
  margin-top: var(--space-24);
  font-size: var(--font-body-lg);
  font-weight: 600;
}

.footer-grid h2 {
  margin: 0 0 var(--space-16);
  font-size: var(--font-body-sm);
  text-transform: uppercase;
  letter-spacing: .08em;
}

.footer-grid nav {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--space-8);
}

.footer-grid nav a {
  color: var(--color-text-secondary);
}

.footer-grid nav a:hover {
  color: var(--color-text-primary);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.footer-grid p {
  color: var(--color-text-secondary);
}

.footer-language {
  margin-top: var(--space-8);
}

.footer-bottom {
  min-height: 64px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-24);
  border-top: var(--border-default) solid var(--color-border-default);
  color: var(--color-text-muted);
  font-size: var(--font-caption);
}

@media (max-width: 980px) {
  .desktop-nav,
  .header-cta {
    display: none;
  }

  .header-inner {
    grid-template-columns: auto 1fr;
  }

  .header-actions {
    justify-self: end;
  }

  .mobile-menu {
    display: block;
    position: relative;
  }

  .mobile-menu nav {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    width: min(300px, calc(100vw - 32px));
    padding: var(--space-12);
    display: grid;
    border: var(--border-default) solid var(--color-border-default);
    border-radius: var(--radius-card);
    background: var(--color-background-elevated);
  }

  .mobile-menu nav a {
    min-height: 48px;
    display: flex;
    align-items: center;
    padding-inline: var(--space-12);
    border-bottom: var(--border-default) solid var(--color-border-subtle);
  }

  .mobile-menu nav a:last-child {
    border-bottom: 0;
  }

  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    gap: var(--space-48);
  }

  .workflow-panel {
    max-width: 680px;
  }

  .section-heading {
    grid-template-columns: minmax(120px, 1fr) minmax(0, 2fr);
  }

  .section-heading > p:last-child {
    grid-column: 2;
  }

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

@media (max-width: 720px) {
  .header-inner,
  .hero,
  .content-section,
  .final-cta,
  .footer-grid,
  .footer-bottom {
    width: min(calc(100% - 32px), var(--container-max));
  }

  .header-inner {
    min-height: 64px;
  }

  .hero {
    padding-block: var(--space-48) var(--space-64);
  }

  .hero h1 {
    font-size: 42px;
    line-height: 50px;
  }

  .hero-actions {
    display: grid;
  }

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

  .content-section {
    padding-block: var(--space-64);
  }

  .workflow-section,
  .evidence-section {
    padding-inline: var(--space-16);
  }

  .section-heading {
    grid-template-columns: 1fr;
    gap: var(--space-16);
    margin-bottom: var(--space-32);
  }

  .section-heading > p:last-child {
    grid-column: auto;
  }

  .problem-grid,
  .workflow-grid,
  .evidence-grid,
  .solutions-grid,
  .why-section,
  .final-cta,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .solution-card,
  .solution-card:nth-child(3),
  .solution-enterprise,
  .solution-muted {
    min-height: auto;
    grid-column: auto;
  }

  .text-link {
    margin-top: var(--space-24);
  }

  .why-section {
    gap: var(--space-32);
  }

  .final-cta {
    margin-block: var(--space-64);
    padding: var(--space-32);
  }

  .cta-action .button {
    width: 100%;
  }

  .footer-grid {
    gap: var(--space-32);
  }

  .footer-bottom {
    min-height: 80px;
    padding-block: var(--space-16);
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: var(--space-4);
  }
}

@media (max-width: 480px) {
  html {
    scroll-padding-top: 72px;
  }

  .header-inner {
    gap: var(--space-8);
  }

  .brand {
    gap: var(--space-8);
  }

  .header-actions {
    gap: var(--space-4);
  }

  .language-switch,
  .mobile-menu summary {
    min-height: 40px;
    padding-inline: var(--space-8);
    font-size: var(--font-caption);
  }

  .hero {
    grid-template-columns: 1fr;
  }

  .hero h1 {
    font-size: 38px;
    line-height: 46px;
  }

  .hero-subtitle {
    font-size: 17px;
    line-height: 27px;
  }

  .north-star,
  .workflow-panel figcaption,
  .workflow-panel ol,
  .panel-boundary,
  .problem-card,
  .solution-card,
  .evidence-card,
  .workflow-step {
    padding-left: var(--space-16);
    padding-right: var(--space-16);
  }

  .problem-grid,
  .workflow-grid,
  .solutions-grid,
  .evidence-grid,
  .why-section,
  .final-cta,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .workflow-step {
    min-height: 0;
  }

  .evidence-card dl > div {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .boundary-note {
    display: grid;
    gap: var(--space-8);
  }

  .final-cta {
    padding: var(--space-24);
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --color-background-default: var(--neutral-950);
    --color-background-elevated: var(--neutral-900);
    --color-surface-default: var(--neutral-900);
    --color-surface-muted: var(--neutral-875);
    --color-border-subtle: var(--neutral-800);
    --color-border-default: var(--neutral-700);
    --color-border-strong: var(--neutral-500);
    --color-text-primary: var(--neutral-050);
    --color-text-secondary: var(--neutral-300);
    --color-text-muted: var(--neutral-500);
    --color-text-inverse: var(--neutral-950);
    --color-primary-default: var(--blue-400);
    --color-primary-hover: var(--blue-400);
    --color-primary-pressed: var(--blue-400);
    --color-success-default: var(--green-400);
    --color-warning-default: var(--amber-400);
  }

  .final-cta {
    background: var(--neutral-875);
    border: var(--border-default) solid var(--color-border-default);
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: .01ms !important;
  }
}