/* EduSynthLab — Synthesis Design System */
@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500&family=Inter:wght@400;500;600&family=Unbounded:wght@500;600;700&display=swap');

:root {
  --black: #0B0D10;
  --slate: #15181D;
  --mist: #ECEFF2;
  --violet: #8B5CF6;
  --cyan: #34D3E0;
  --ash: #868C96;
  --violet-dim: rgba(139, 92, 246, 0.15);
  --cyan-dim: rgba(52, 211, 224, 0.12);
  --mist-90: rgba(236, 239, 242, 0.9);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
  --header-h: 72px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--mist);
  background: var(--black);
  min-height: 100vh;
}

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

a {
  color: var(--cyan);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover, a:focus-visible {
  color: var(--violet);
  text-decoration: underline;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

h1, h2, h3 {
  font-family: 'Unbounded', sans-serif;
  font-weight: 600;
  line-height: 1.25;
  color: var(--mist);
}

h1 { font-size: clamp(2rem, 5vw, 3.25rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); margin-bottom: 1rem; }
h3 { font-size: clamp(1.125rem, 2.5vw, 1.5rem); margin-bottom: 0.75rem; }

p { margin-bottom: 1rem; }
p:last-child { margin-bottom: 0; }

.mono {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
}

/* Surfaces */
.surface-black { background: var(--black); color: var(--mist); }
.surface-mist { background: var(--mist); color: var(--black); }
.surface-slate { background: var(--slate); color: var(--mist); }
.surface-violet { background: var(--violet); color: var(--black); }

.surface-mist a { color: #5B21B6; }
.surface-mist a:hover { color: #0B0D10; }

/* Layout */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 5rem 0;
}

.section--compact {
  padding: 3rem 0;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  transition: background var(--transition), box-shadow var(--transition), backdrop-filter var(--transition);
}

.site-header.is-transparent {
  background: transparent;
}

.site-header.is-sticky {
  background: var(--mist-90);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 rgba(11, 13, 16, 0.08);
}

.site-header.is-sticky .logo-text { color: var(--black); }
.site-header.is-sticky .nav-link { color: var(--black); }
.site-header.is-sticky .nav-link:hover,
.site-header.is-sticky .nav-link.is-active { color: var(--violet); }
.site-header.is-sticky .nav-toggle span { background: var(--black); }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  text-decoration: none;
}

.logo:hover { text-decoration: none; }

.logo-icon {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}

.logo-text {
  font-family: 'Unbounded', sans-serif;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--mist);
  transition: color var(--transition);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--mist);
  transition: background var(--transition);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  list-style: none;
}

.nav-link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--mist);
  text-decoration: none;
  transition: color var(--transition);
}

.nav-link:hover,
.nav-link.is-active {
  color: var(--cyan);
  text-decoration: none;
}

/* Hero — Synthesis full-bleed */
.hero-synthesis {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: var(--header-h);
}

.hero-synthesis__bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

.hero-synthesis__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(11, 13, 16, 0.92) 0%,
    rgba(11, 13, 16, 0.75) 45%,
    rgba(21, 24, 29, 0.85) 100%
  );
}

.hero-synthesis__graph {
  position: absolute;
  inset: 0;
  opacity: 0.35;
  pointer-events: none;
}

.hero-synthesis__content {
  position: relative;
  z-index: 2;
  width: 100%;
  padding: 4rem 0 3rem;
  align-self: flex-end;
}

.hero-synthesis__toprow {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 0.75rem;
}

.hero-synthesis__lablabel {
  color: var(--violet);
}

.hero-synthesis__rule {
  border: none;
  border-top: 1px solid rgba(236, 239, 242, 0.25);
  margin: 0 0 1.5rem;
}

.hero-synthesis__eyebrow {
  font-family: 'Inter', sans-serif;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--violet);
  margin-bottom: 1rem;
}

.hero-synthesis__underline {
  text-decoration: underline;
  text-decoration-color: var(--violet);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 2px;
}

.hero-synthesis__trust {
  margin-top: 2rem;
  font-size: 0.75rem;
  color: var(--ash);
  letter-spacing: 0.04em;
}

.hero-synthesis__badge {
  display: inline-block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.75rem;
  color: var(--cyan);
  background: var(--cyan-dim);
  padding: 0.375rem 0.875rem;
  border-radius: 999px;
  margin-bottom: 1.5rem;
  border: 1px solid rgba(52, 211, 224, 0.25);
}

.hero-synthesis__title {
  max-width: 18ch;
  margin-bottom: 1.25rem;
  font-size: clamp(2.75rem, 5.5vw, 5.125rem);
}

.hero-synthesis__tagline {
  font-size: clamp(1rem, 1.8vw, 1.125rem);
  color: rgba(236, 239, 242, 0.85);
  max-width: 34rem;
  margin-bottom: 2rem;
  line-height: 1.65;
}

.hero-synthesis__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

/* Page hero (inner pages) */
.page-hero {
  padding: calc(var(--header-h) + 4rem) 0 3rem;
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  top: 0;
  right: -10%;
  width: 50%;
  height: 100%;
  background: radial-gradient(ellipse at center, var(--violet-dim) 0%, transparent 70%);
  pointer-events: none;
}

.page-hero__label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.75rem;
  color: var(--violet);
  margin-bottom: 0.75rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  font-family: 'Inter', sans-serif;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition), color var(--transition), transform 0.2s ease;
}

.btn:hover { text-decoration: none; transform: translateY(-1px); }

.btn--primary {
  background: var(--violet);
  color: var(--mist);
}

.btn--primary:hover {
  background: #7C3AED;
  color: var(--mist);
}

.btn--ghost {
  background: transparent;
  color: var(--mist);
  border: 1px solid rgba(236, 239, 242, 0.35);
}

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

.btn--dark {
  background: var(--black);
  color: var(--mist);
}

.btn--dark:hover {
  background: var(--slate);
  color: var(--cyan);
}

/* Frosted panel cards */
.frost-card {
  background: rgba(21, 24, 29, 0.65);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(236, 239, 242, 0.08);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: border-color var(--transition), transform var(--transition);
}

.frost-card:hover {
  border-color: rgba(139, 92, 246, 0.3);
  transform: translateY(-2px);
}

.frost-card--light {
  background: rgba(236, 239, 242, 0.08);
}

/* Knowledge graph motif */
.kg-motif {
  position: relative;
}

.kg-motif svg {
  width: 100%;
  height: auto;
}

.kg-node {
  fill: var(--violet);
  transition: fill 0.4s ease;
}

.kg-node--cyan { fill: var(--cyan); }

.kg-edge {
  stroke: var(--violet);
  stroke-width: 1;
  opacity: 0.4;
  transition: opacity 0.4s ease, stroke 0.4s ease;
}

.kg-edge.is-active {
  opacity: 1;
  stroke: var(--cyan);
}

.kg-label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 9px;
  fill: var(--ash);
}

/* Grid layouts */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

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

.grid-auto {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

/* Service cards */
.service-card {
  padding: 2rem;
  border-radius: var(--radius-lg);
  background: var(--slate);
  border: 1px solid rgba(236, 239, 242, 0.06);
  transition: border-color var(--transition);
}

.service-card:hover {
  border-color: rgba(139, 92, 246, 0.35);
}

.service-card__price {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8125rem;
  color: var(--cyan);
  margin-top: 1rem;
}

.service-card__icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.25rem;
  color: var(--violet);
}

/* Work / engagement cards */
.engagement-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: center;
  padding: 2.5rem 0;
  border-bottom: 1px solid rgba(236, 239, 242, 0.06);
}

.engagement-card:last-child { border-bottom: none; }

.engagement-card__meta {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.75rem;
  color: var(--ash);
  margin-bottom: 0.5rem;
}

.engagement-card__img {
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 4/3;
  object-fit: cover;
}

/* FAQ */
.faq-list { list-style: none; }

.faq-item {
  border-bottom: 1px solid rgba(236, 239, 242, 0.08);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1.5rem 0;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  font-family: 'Unbounded', sans-serif;
  font-size: 1rem;
  font-weight: 500;
  color: var(--mist);
}

.faq-question::after {
  content: '+';
  font-size: 1.5rem;
  color: var(--violet);
  flex-shrink: 0;
  transition: transform var(--transition);
}

.faq-item.is-open .faq-question::after {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
}

.faq-item.is-open .faq-answer {
  max-height: 800px;
  padding-bottom: 1.5rem;
}

.faq-answer p {
  color: var(--ash);
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--mist);
}

.surface-mist .form-label { color: var(--black); }

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 0.875rem 1rem;
  font-family: 'Inter', sans-serif;
  font-size: 1rem;
  border: 1px solid rgba(236, 239, 242, 0.15);
  border-radius: var(--radius);
  background: var(--slate);
  color: var(--mist);
  transition: border-color var(--transition);
}

.surface-mist .form-input,
.surface-mist .form-textarea,
.surface-mist .form-select {
  background: #fff;
  color: var(--black);
  border-color: rgba(11, 13, 16, 0.15);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--violet);
  outline: none;
}

.form-textarea { min-height: 140px; resize: vertical; }

.form-check {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: 0.875rem;
}

.form-check input { margin-top: 0.25rem; flex-shrink: 0; }

.hp-field {
  position: absolute;
  left: -9999px;
  opacity: 0;
  height: 0;
  width: 0;
  overflow: hidden;
}

/* Split layout */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.split__img {
  border-radius: var(--radius-lg);
  overflow: hidden;
}

/* Stats strip */
.stats-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
  padding: 2rem 0;
}

.stat-item__value {
  font-family: 'Unbounded', sans-serif;
  font-size: 1.75rem;
  color: var(--violet);
}

.stat-item__label {
  font-size: 0.875rem;
  color: var(--ash);
}

/* Footer */
.site-footer {
  padding: 4rem 0 2rem;
  border-top: 1px solid rgba(236, 239, 242, 0.06);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2.5rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  color: var(--ash);
  font-size: 0.875rem;
  margin-top: 1rem;
}

.footer-heading {
  font-family: 'Unbounded', sans-serif;
  font-size: 0.8125rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--mist);
}

.footer-links {
  list-style: none;
}

.footer-links li { margin-bottom: 0.5rem; }

.footer-links a {
  font-size: 0.875rem;
  color: var(--ash);
}

.footer-links a:hover { color: var(--cyan); }

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(236, 239, 242, 0.06);
  font-size: 0.8125rem;
  color: var(--ash);
}

.footer-disclaimer-block {
  padding-top: 1.5rem;
}

.footer-disclaimer {
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--ash);
  max-width: 72rem;
}

/* Cookie banner */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 2000;
  padding: 1.25rem 1.5rem;
  background: var(--slate);
  border-top: 1px solid rgba(139, 92, 246, 0.25);
  transform: translateY(100%);
  transition: transform 0.4s ease;
}

.cookie-banner.is-visible {
  transform: translateY(0);
}

.cookie-banner__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.cookie-banner__text {
  flex: 1;
  min-width: 240px;
  font-size: 0.875rem;
  color: var(--ash);
}

.cookie-banner__actions {
  display: flex;
  gap: 0.75rem;
}

/* Scroll reveal */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal--delay-1 { transition-delay: 0.1s; }
.reveal--delay-2 { transition-delay: 0.2s; }
.reveal--delay-3 { transition-delay: 0.3s; }

/* Legal prose */
.legal-prose h2 {
  margin-top: 2.5rem;
  font-size: 1.25rem;
}

.legal-prose h3 {
  margin-top: 1.75rem;
  font-size: 1.0625rem;
}

.legal-prose ul, .legal-prose ol {
  margin: 1rem 0 1rem 1.5rem;
  color: var(--ash);
}

.legal-prose li { margin-bottom: 0.5rem; }

/* 404 */
.error-page {
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 4rem 1.5rem;
}

.error-page__code {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.875rem;
  color: var(--violet);
  margin-bottom: 1rem;
}

/* Utility */
.text-ash { color: var(--ash); }
.text-violet { color: var(--violet); }
.text-cyan { color: var(--cyan); }
.text-center { text-align: center; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.mt-2 { margin-top: 2rem; }
.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;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
  html { scroll-behavior: auto; }
}

/* Responsive */
@media (max-width: 900px) {
  .grid-3 { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; }
  .engagement-card { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

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

  .nav-list {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--mist-90);
    backdrop-filter: blur(12px);
    padding: 1.5rem;
    gap: 1rem;
    transform: translateY(-120%);
    opacity: 0;
    transition: transform var(--transition), opacity var(--transition);
    pointer-events: none;
  }

  .nav-list.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .site-header.is-transparent .nav-list .nav-link,
  .nav-list .nav-link {
    color: var(--black);
  }

  .footer-grid { grid-template-columns: 1fr; }
  .section { padding: 3.5rem 0; }
}