:root {
  color-scheme: light;
  --ink: #1d1d1b;
  --paper: #f2eee5;
  --paper-soft: #f8f5ef;
  --line: #d8d0c4;
  --muted: #716b62;
  --accent: #df5b2d;
  --accent-dark: #b6411b;
  --accent-on-paper: #b6411b;
  --accent-on-night: #ed7650;
  --night: #1c2024;
  --night-soft: #292e34;
  --night-text: #f5f1e8;
  --success: #356144;
  --success-bg: #dce9df;
  --hold: #85501f;
  --hold-bg: #f6dfc7;
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.65;
}

a {
  color: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -5rem;
  z-index: 10;
  padding: 0.7rem 1rem;
  background: var(--ink);
  color: white;
}

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

.site-header {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 2rem;
  padding: 1.1rem clamp(1rem, 4vw, 4rem);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  text-decoration: none;
}

.brand::before,
.brand-mark {
  width: 0.65rem;
  height: 0.65rem;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0.35rem rgba(223, 91, 45, 0.13);
  content: "";
}

.site-header nav {
  display: flex;
  justify-content: center;
  gap: 1.4rem;
}

.site-header nav a {
  color: var(--muted);
  font-size: 0.9rem;
  text-decoration: none;
  transition: color 160ms ease;
}

.site-header nav a:hover {
  color: var(--ink);
}

.safety-note {
  margin: 0;
  color: var(--success);
  font-size: 0.78rem;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(18rem, 0.8fr);
  align-items: center;
  gap: clamp(2rem, 6vw, 6rem);
  max-width: 76rem;
  margin: 0 auto;
  padding: clamp(4rem, 9vw, 8rem) clamp(1rem, 4vw, 4rem);
}

.eyebrow,
.section-number {
  margin: 0 0 0.8rem;
  color: var(--accent-on-paper);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.dark-section .eyebrow,
.dark-section .section-number,
.agent-summary .eyebrow,
.agent-summary .section-number {
  color: var(--accent-on-night);
}

h1,
h2,
h3,
p {
  text-wrap: pretty;
}

h1 {
  max-width: 13em;
  margin: 0;
  font-size: clamp(2.35rem, 6vw, 5.6rem);
  line-height: 1.05;
  letter-spacing: -0.04em;
}

h2 {
  max-width: 22em;
  margin: 0 0 1rem;
  font-size: clamp(1.8rem, 4vw, 3.2rem);
  line-height: 1.15;
  letter-spacing: -0.025em;
}

h3 {
  line-height: 1.3;
}

.hero-copy > p:not(.eyebrow),
.hero-lead {
  max-width: 42rem;
  margin: 1.5rem 0 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.8rem;
  padding: 0.65rem 1rem;
  border-radius: 0.45rem;
  font-weight: 700;
  text-decoration: none;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease;
}

.button-primary {
  background: var(--ink);
  color: white;
}

.button-primary:hover {
  background: var(--accent-dark);
}

.button-secondary {
  border: 1px solid var(--line);
}

.button-secondary:hover {
  border-color: var(--ink);
}

.agent-summary {
  padding: 1.3rem;
  border-radius: 0.8rem;
  background: var(--night);
  color: var(--night-text);
  box-shadow: 0 1.5rem 3.5rem rgba(41, 33, 24, 0.18);
}

.summary-head {
  color: #b7bab6;
}

.summary-head h2 {
  max-width: none;
  margin: 0;
  color: var(--night-text);
  font-size: 1.35rem;
  letter-spacing: -0.01em;
}

.summary-head strong,
.agent-summary li strong {
  color: #9ec5aa;
}

.agent-summary ol {
  display: grid;
  gap: 0.7rem;
  margin: 1.2rem 0 0;
  padding: 0;
  list-style: none;
}

.agent-summary li {
  display: grid;
  grid-template-columns: 1.5rem 1fr auto;
  align-items: center;
  gap: 0.6rem;
  padding: 0.75rem;
  border-radius: 0.4rem;
  background: var(--night-soft);
  font-size: 0.85rem;
}

.agent-summary li span {
  color: #ed7650;
  font-weight: 700;
}

.proof-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.proof-strip div {
  padding: 1.2rem;
  border-right: 1px solid var(--line);
  text-align: center;
}

.proof-strip div:last-child {
  border-right: 0;
}

.proof-strip strong,
.proof-strip span {
  display: block;
}

.proof-strip span {
  margin-top: 0.2rem;
  color: var(--muted);
  font-size: 0.78rem;
}

.section {
  max-width: 76rem;
  margin: 0 auto;
  padding: clamp(4rem, 8vw, 7rem) clamp(1rem, 4vw, 4rem);
}

.section-heading > p:last-child,
.section-intro {
  max-width: 48rem;
  color: var(--muted);
}

.case-tabs {
  display: flex;
  gap: 0.65rem;
  margin: 2rem 0 1rem;
  padding-bottom: 0.35rem;
  overflow-x: auto;
}

.case-tabs button {
  flex: 0 0 auto;
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--line);
  border-radius: 0.45rem;
  background: transparent;
  color: var(--ink);
  font: inherit;
  cursor: pointer;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease;
}

.case-tabs button:hover {
  border-color: var(--ink);
}

.case-tabs button[aria-pressed="true"] {
  border-color: var(--ink);
  background: var(--ink);
  color: white;
}

.demo-grid {
  display: grid;
  grid-template-columns: 1fr 0.82fr 1fr;
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 0.8rem;
  background: var(--line);
}

.demo-panel {
  min-width: 0;
  min-height: 22rem;
  padding: 1.35rem;
  background: var(--paper-soft);
}

.demo-panel header {
  display: flex;
  justify-content: space-between;
  gap: 0.8rem;
  margin-bottom: 1.2rem;
  color: var(--muted);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.demo-panel h3 {
  margin-top: 0;
}

.process-panel {
  background: var(--night);
  color: var(--night-text);
}

.process-panel header {
  color: #aeb1ad;
}

.fact-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin: 1.4rem 0 0;
  padding: 0;
  list-style: none;
}

.fact-list li {
  padding: 0.3rem 0.55rem;
  border-radius: 999px;
  background: #e8dfd3;
  color: #5d4e40;
  font-size: 0.74rem;
}

.process-list {
  display: grid;
  gap: 0.65rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.process-list li {
  display: grid;
  grid-template-columns: 1.5rem 1fr auto;
  align-items: center;
  gap: 0.55rem;
  padding: 0.75rem;
  border-radius: 0.4rem;
  background: var(--night-soft);
  font-size: 0.8rem;
}

.process-list li span {
  color: #ed7650;
  font-weight: 700;
}

.process-list li strong {
  color: #9ec5aa;
}

.process-list li strong.state-hold {
  color: #f1b171;
}

.status {
  display: inline-block;
  margin: 0 0 1rem;
  padding: 0.3rem 0.55rem;
  border-radius: 999px;
  font-size: 0.76rem;
  font-weight: 700;
}

.status-success {
  background: var(--success-bg);
  color: var(--success);
}

.status-hold {
  background: var(--hold-bg);
  color: var(--hold);
}

.verification {
  margin-top: 1.4rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
}

.feature-grid,
.standards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin-top: 2rem;
}

.feature-grid article {
  padding: 1.2rem;
  border-top: 0.18rem solid var(--ink);
  background: #e8e2d8;
}

.feature-grid h3,
.standards-grid h3 {
  margin-top: 0;
}

.dark-section {
  max-width: none;
  padding-inline: max(1rem, calc((100% - 68rem) / 2));
  background: var(--night);
  color: var(--night-text);
}

.dark-section .section-heading > p:last-child {
  color: #c1c2bd;
}

.standards-grid {
  grid-template-columns: repeat(3, 1fr);
}

.standards-grid article {
  padding: 1.2rem;
  border: 1px solid #353b42;
  background: #23282d;
}

.standards-grid p {
  color: #c1c2bd;
}

details {
  margin-top: 1.5rem;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

summary {
  padding: 1rem 0;
  font-weight: 700;
  cursor: pointer;
}

.workflow-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.65rem 2rem;
  padding: 0 0 1.5rem 1.5rem;
}

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

.boundary-grid article {
  padding: 1.5rem;
  border: 1px solid var(--line);
  background: var(--paper-soft);
}

.boundary-grid h3 {
  margin-top: 0;
}

.boundary-grid li,
.evidence-list li {
  margin: 0.55rem 0;
}

.evidence-list {
  max-width: 48rem;
  padding-left: 1.25rem;
}

.contact-section {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: center;
  max-width: 76rem;
  margin: 0 auto;
  padding: clamp(4rem, 8vw, 7rem) clamp(1rem, 4vw, 4rem);
  background: var(--accent-dark);
  color: white;
}

.contact-section .section-number {
  color: white;
  opacity: 1;
}

.contact-section h2 {
  margin-bottom: 0.5rem;
}

.contact-section figure {
  margin: 0;
  text-align: center;
}

.contact-section img {
  display: block;
  width: min(16rem, 100%);
  height: auto;
  aspect-ratio: auto;
  padding: 0.6rem;
  border-radius: 0.65rem;
  background: white;
  object-fit: contain;
}

.contact-section figcaption {
  margin-top: 0.45rem;
  font-size: 0.75rem;
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.5rem clamp(1rem, 4vw, 4rem);
  background: var(--ink);
  color: #d9d4ca;
  font-size: 0.78rem;
}

footer p {
  margin: 0;
}

@media (max-width: 960px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .site-header nav {
    display: none;
  }

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

  .proof-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .proof-strip div:nth-child(even) {
    border-right: 0;
  }

  .proof-strip div:nth-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }

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

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

  .demo-panel {
    min-height: auto;
  }
}

@media (max-width: 760px) {
  .site-header {
    grid-template-columns: 1fr;
    gap: 0.45rem;
  }

  .safety-note {
    text-align: left;
  }

  h1 {
    font-size: clamp(2.3rem, 13vw, 4.2rem);
  }

  .proof-strip,
  .feature-grid,
  .standards-grid,
  .workflow-list,
  .boundary-grid {
    grid-template-columns: 1fr;
  }

  .proof-strip div:nth-child(n) {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .proof-strip div:last-child {
    border-bottom: 0;
  }

  .agent-summary li,
  .process-list li {
    grid-template-columns: 1.5rem minmax(0, 1fr);
  }

  .agent-summary li strong,
  .process-list li strong {
    grid-column: 2;
  }

  .contact-section {
    grid-template-columns: 1fr;
  }

  .contact-section figure {
    justify-self: start;
  }

  footer {
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}