/* LBAI / E2C marketing site — English-only static framework */

:root {
  --zinc-50: #fafafa;
  --zinc-100: #f4f4f5;
  --zinc-200: #e4e4e7;
  --zinc-300: #d4d4d8;
  --zinc-400: #a1a1aa;
  --zinc-500: #71717a;
  --zinc-600: #52525b;
  --zinc-700: #3f3f46;
  --zinc-800: #27272a;
  --zinc-900: #18181b;
  --accent: #2563eb;
  --max-w: 72rem;
  --header-h: 3.5rem;
  font-family: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--zinc-50);
  color: var(--zinc-900);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

img {
  max-width: 100%;
  height: auto;
}

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

.sr-only:focus {
  position: fixed;
  left: 1rem;
  top: 1rem;
  z-index: 200;
  width: auto;
  height: auto;
  padding: 0.5rem 0.75rem;
  margin: 0;
  overflow: visible;
  clip: auto;
  white-space: normal;
  background: #fff;
  border-radius: 0.375rem;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.12);
}

/* Layout */
.site-shell {
  display: flex;
  min-height: 100dvh;
  flex-direction: column;
}

#main {
  flex: 1;
}

.container {
  width: 100%;
  max-width: var(--max-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1rem;
  padding-right: 1rem;
}

@media (min-width: 640px) {
  .container {
    padding-left: 1.5rem;
    padding-right: 1.5rem;
  }
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid rgba(228, 228, 231, 0.9);
  background: rgba(250, 250, 250, 0.85);
  backdrop-filter: blur(12px);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: var(--header-h);
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1rem;
}

@media (min-width: 640px) {
  .site-header__inner {
    padding: 0 1.5rem;
  }
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--zinc-900);
  text-decoration: none;
}

.site-logo:hover {
  color: var(--zinc-900);
}

.site-logo__img {
  width: 2.5rem;
  height: 2.5rem;
  flex-shrink: 0;
  object-fit: contain;
}

.site-logo__img--footer {
  width: 2rem;
  height: 2rem;
}

.site-logo__text {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1;
}

.site-logo__text--footer {
  font-size: 1.125rem;
}

.site-logo--footer {
  margin: 0;
}

.site-nav {
  display: none;
  align-items: center;
  gap: 0.25rem;
}

@media (min-width: 768px) {
  .site-nav {
    display: flex;
  }
}

.site-nav a {
  padding: 0.5rem 0.75rem;
  font-size: 0.875rem;
  color: var(--zinc-600);
  border-radius: 0.375rem;
  transition: background 0.15s, color 0.15s;
}

.site-nav a:hover,
.site-nav a.is-active {
  background: var(--zinc-100);
  color: var(--zinc-900);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.375rem 0.75rem;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 0.375rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}

.btn--ghost {
  border-color: var(--zinc-300);
  background: #fff;
  color: var(--zinc-800);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04);
}

.btn--ghost:hover {
  border-color: var(--zinc-400);
}

.btn--primary {
  background: var(--zinc-900);
  color: #fff;
}

.btn--primary:hover {
  background: var(--zinc-800);
}

.btn--white {
  background: #fff;
  color: var(--zinc-900);
}

.btn--white:hover {
  background: var(--zinc-100);
}

.btn--outline-light {
  border-color: var(--zinc-600);
  color: #fff;
  background: transparent;
}

.btn--outline-light:hover {
  border-color: var(--zinc-500);
}

.btn--lg {
  padding: 0.625rem 1.25rem;
}

.menu-toggle {
  display: flex;
  padding: 0.5rem;
  font-size: 1.25rem;
  line-height: 1;
  background: none;
  border: none;
  color: var(--zinc-700);
  cursor: pointer;
}

@media (min-width: 768px) {
  .menu-toggle {
    display: none;
  }

  .btn--ghost.hide-sm {
    display: inline-flex;
  }
}

@media (max-width: 767px) {
  .btn--ghost.hide-sm {
    display: none;
  }
}

.site-nav-mobile {
  display: none;
  flex-wrap: wrap;
  gap: 0.25rem;
  padding: 0.5rem 1rem 0.75rem;
  border-top: 1px solid var(--zinc-100);
}

.site-nav-mobile.is-open {
  display: flex;
}

.site-nav-mobile a {
  padding: 0.375rem 0.5rem;
  font-size: 0.75rem;
  color: var(--zinc-600);
  border-radius: 0.25rem;
}

.site-nav-mobile a:hover,
.site-nav-mobile a.is-active {
  background: var(--zinc-100);
  color: var(--zinc-900);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--zinc-200);
  background: #fff;
  padding: 3rem 0 2rem;
  margin-top: auto;
}

.site-footer__top {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

@media (min-width: 768px) {
  .site-footer__top {
    flex-direction: row;
    align-items: flex-start;
    justify-content: space-between;
    gap: 3rem;
  }
}

.site-footer__brand {
  flex: 0 1 18.5rem;
  max-width: 18.5rem;
}

.site-footer__tagline {
  margin: 0.875rem 0 0;
  font-size: 0.875rem;
  line-height: 1.65;
  color: var(--zinc-500);
}

.site-footer__nav {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.75rem 2.5rem;
  width: 100%;
}

@media (min-width: 480px) {
  .site-footer__nav {
    grid-template-columns: repeat(3, minmax(6.5rem, 1fr));
  }
}

@media (min-width: 768px) {
  .site-footer__nav {
    flex: 0 1 auto;
    width: auto;
    max-width: 26rem;
    margin-left: auto;
    gap: 2rem 3rem;
  }
}

.site-footer__col h3 {
  margin: 0 0 0.875rem;
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--zinc-500);
}

.site-footer__col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer__col li + li {
  margin-top: 0.625rem;
}

.site-footer__col a {
  display: inline-block;
  font-size: 0.875rem;
  line-height: 1.4;
  color: var(--zinc-600);
  transition: color 0.15s;
}

.site-footer__col a:hover {
  color: var(--zinc-900);
}

.site-footer__bottom {
  margin-top: 2.25rem;
  padding-top: 2rem;
  border-top: 1px solid var(--zinc-200);
  padding-top: 1.25rem;
  border-top: 1px solid var(--zinc-100);
  font-size: 0.8125rem;
  line-height: 1.55;
  color: var(--zinc-400);
}

/* Hero */
.hero {
  border-bottom: 1px solid var(--zinc-200);
  background: linear-gradient(180deg, #fff 0%, var(--zinc-50) 100%);
}

.hero__inner {
  padding: 5rem 0 6rem;
}

@media (min-width: 1024px) {
  .hero__inner {
    padding: 7rem 0 7rem;
  }
}

.eyebrow {
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--zinc-500);
}

.hero h1 {
  margin: 1rem 0 0;
  max-width: 48rem;
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.03em;
}

.hero__lead {
  margin: 1.5rem 0 0;
  max-width: 42rem;
  font-size: 1.125rem;
  color: var(--zinc-600);
  line-height: 1.65;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2.5rem;
}

.link-text {
  display: inline-flex;
  align-items: center;
  padding: 0.625rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--zinc-700);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.link-text:hover {
  color: var(--zinc-900);
}

/* Sections */
.section {
  padding: 4rem 0;
}

@media (min-width: 1024px) {
  .section {
    padding: 5rem 0;
  }
}

.section--border {
  border-top: 1px solid var(--zinc-200);
  border-bottom: 1px solid var(--zinc-200);
  background: #fff;
}

.section__label {
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--zinc-500);
}

.section h2 {
  margin: 0.5rem 0 0;
  max-width: 42rem;
  font-size: 1.75rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.25;
}

.section__intro {
  margin: 1rem 0 0;
  max-width: 48rem;
  color: var(--zinc-600);
}

/* Cards */
.card-grid {
  display: grid;
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.card-grid--2 {
  grid-template-columns: 1fr;
}

.card-grid--3 {
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .card-grid--2 {
    grid-template-columns: repeat(2, 1fr);
  }

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

.card {
  border: 1px solid var(--zinc-200);
  border-radius: 0.75rem;
  background: #fff;
  padding: 1.5rem;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.03);
}

.card h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.card p {
  margin: 0.75rem 0 0;
  font-size: 0.9375rem;
  color: var(--zinc-600);
  line-height: 1.6;
}

.card--muted {
  background: var(--zinc-50);
  border-color: var(--zinc-100);
}

.pill-list {
  display: grid;
  gap: 1rem;
  margin-top: 2rem;
  list-style: none;
  padding: 0;
}

@media (min-width: 640px) {
  .pill-list {
    grid-template-columns: repeat(3, 1fr);
  }
}

.pill-list li {
  padding: 0.875rem 1rem;
  font-size: 0.875rem;
  color: var(--zinc-700);
  background: var(--zinc-50);
  border: 1px solid var(--zinc-100);
  border-radius: 0.5rem;
}

/* CTA band */
.cta-band {
  border-radius: 1rem;
  border: 1px solid var(--zinc-200);
  background: var(--zinc-900);
  padding: 3rem 2rem;
  text-align: center;
}

.cta-band h2 {
  margin: 0;
  color: #fff;
  font-size: 1.125rem;
  font-weight: 500;
  max-width: none;
}

.cta-band p {
  margin: 0.5rem 0 0;
  font-size: 0.875rem;
  color: var(--zinc-400);
}

.cta-band__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 2rem;
}

/* Page intro (inner pages) */
.page-intro {
  border-bottom: 1px solid var(--zinc-200);
  background: linear-gradient(180deg, #fff, var(--zinc-50));
  padding: 3.5rem 0 3rem;
}

.page-intro h1 {
  margin: 0;
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.page-intro p {
  margin: 1rem 0 0;
  max-width: 42rem;
  color: var(--zinc-600);
  font-size: 1.0625rem;
}

.page-body {
  padding: 3.5rem 0 4rem;
}

.page-body--narrow {
  max-width: 48rem;
}

.center-card {
  max-width: 32rem;
  margin: 0 auto;
  padding: 2rem;
  text-align: center;
  border: 1px solid var(--zinc-200);
  border-radius: 1rem;
  background: #fff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.center-card p {
  margin: 0;
  font-size: 0.875rem;
  color: var(--zinc-600);
}

.center-card .btn {
  margin-top: 2rem;
}

.waitlist-box {
  scroll-margin-top: 6rem;
  margin-top: 2.5rem;
  padding: 2rem;
  text-align: center;
  border: 1px dashed var(--zinc-300);
  border-radius: 0.75rem;
  background: var(--zinc-50);
}

.waitlist-box h2 {
  margin: 0;
  font-size: 1.125rem;
}

.waitlist-box p {
  margin: 0.5rem 0 0;
  font-size: 0.875rem;
  color: var(--zinc-600);
}

.waitlist-box .btn {
  margin-top: 1.5rem;
}

.prose {
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--zinc-600);
}

.prose p {
  margin: 0 0 1rem;
}

.prose p:last-child {
  margin-bottom: 0;
}

.prose-legal h2 {
  margin: 2rem 0 0.75rem;
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--zinc-900);
}

.prose-legal h2:first-child {
  margin-top: 0;
}

.prose-legal h3 {
  margin: 1.25rem 0 0.5rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--zinc-800);
}

.prose-legal ul {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
}

.prose-legal li {
  margin-bottom: 0.35rem;
}

.prose-legal a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.legal-notice {
  margin-bottom: 1.5rem;
  padding: 1rem 1.25rem;
  font-size: 0.8125rem;
  color: var(--zinc-600);
  background: var(--zinc-50);
  border: 1px solid var(--zinc-200);
  border-radius: 0.5rem;
}

.quote-block {
  margin: 2rem 0 0;
  padding: 1.25rem 1.5rem;
  border-left: 3px solid var(--zinc-300);
  background: var(--zinc-50);
  border-radius: 0 0.5rem 0.5rem 0;
}

.quote-block p {
  margin: 0;
  font-size: 1rem;
  font-weight: 500;
  color: var(--zinc-800);
  line-height: 1.5;
}

.flow-steps {
  display: grid;
  gap: 0.75rem;
  margin-top: 2rem;
  list-style: none;
  padding: 0;
}

@media (min-width: 768px) {
  .flow-steps {
    grid-template-columns: repeat(4, 1fr);
  }
}

.flow-steps li {
  padding: 1rem;
  font-size: 0.8125rem;
  font-weight: 500;
  text-align: center;
  color: var(--zinc-700);
  background: #fff;
  border: 1px solid var(--zinc-200);
  border-radius: 0.5rem;
}

.flow-steps .step-num {
  display: block;
  margin-bottom: 0.35rem;
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--zinc-400);
}

.link-arrow {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--zinc-900);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.link-arrow:hover {
  color: var(--zinc-600);
}

.stack {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.muted {
  font-size: 0.875rem;
  color: var(--zinc-400);
}

/* Architecture diagram */
.arch-flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.5rem;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--zinc-700);
}

.arch-flow span {
  padding: 0.35rem 0.65rem;
  background: var(--zinc-100);
  border-radius: 0.375rem;
  border: 1px solid var(--zinc-200);
}

.arch-flow .arrow {
  color: var(--zinc-400);
  padding: 0;
  background: none;
  border: none;
}