:root {
  --bg-slate: #141922;
  --panel-slate: #1e2530;
  --surface-slate: #28313f;
  --border-slate: #3b4759;
  --lime: #a3e635;
  --lime-hover: #bef264;
  --lime-dark: #65a30d;
  --text-pure: #ffffff;
  --text-muted: #cbd5e1;
  --text-dim: #94a3b8;
  --radius-xl: 20px;
  --radius-md: 10px;
  --font-serif: Charter, Cambria, Georgia, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

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

body {
  background-color: var(--bg-slate);
  color: var(--text-pure);
  font-family: var(--font-serif);
  line-height: 1.65;
  font-size: 1.05rem;
  overflow-x: hidden;
}

h1, h2, h3, h4, .tagline {
  font-family: var(--font-serif);
  font-weight: normal;
  letter-spacing: -0.01em;
}

p {
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

a {
  color: var(--text-pure);
  text-decoration: none;
  transition: all 0.25s ease;
}

.text-lime {
  color: var(--lime);
}

.structural-tag {
  font-family: var(--font-sans);
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  font-weight: 700;
  color: var(--lime);
  display: inline-block;
  margin-bottom: 0.6rem;
}

/* Header & Navigation */
header.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(30, 37, 48, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-slate);
  transition: background 0.3s ease;
}

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-logo {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--text-pure);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.brand-logo span {
  color: var(--lime);
}

nav.main-nav {
  display: flex;
  gap: 1.8rem;
  align-items: center;
}

nav.main-nav a {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  position: relative;
  padding-bottom: 4px;
}

nav.main-nav a:hover,
nav.main-nav a.active {
  color: var(--lime);
}

nav.main-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: var(--lime);
  transition: width 0.25s ease;
}

nav.main-nav a:hover::after,
nav.main-nav a.active::after {
  width: 100%;
}

/* Layout Wrappers */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section-block {
  padding: 5rem 0;
}

/* Horizontal Accent Divider Band */
.accent-band {
  background: var(--lime);
  color: #141922;
  padding: 1.5rem 0;
  font-family: var(--font-sans);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.85rem;
  border-top: 1px solid rgba(0,0,0,0.1);
  border-bottom: 1px solid rgba(0,0,0,0.1);
}

.accent-band-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
  align-items: center;
}

/* Hero Section */
.hero-split {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 3rem;
  align-items: center;
  padding: 4.5rem 0 3.5rem;
}

.hero-content h1 {
  font-size: 3.2rem;
  line-height: 1.15;
  margin-bottom: 1.5rem;
  color: var(--text-pure);
}

.hero-content p.thesis {
  font-size: 1.25rem;
  line-height: 1.6;
  color: var(--text-muted);
  margin-bottom: 2.2rem;
}

.cta-button {
  display: inline-block;
  background-color: var(--lime);
  color: #0f172a;
  padding: 0.9rem 2rem;
  border-radius: var(--radius-xl);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.2s;
}

.cta-button:hover {
  background-color: var(--lime-hover);
  transform: translateY(-2px);
}

.hero-visual {
  position: relative;
}

.rounded-window {
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--border-slate);
  background: var(--panel-slate);
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.rounded-window img {
  width: 100%;
  height: 440px;
  object-fit: cover;
  display: block;
}

/* Metric Ribbon */
.metric-ribbon {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  background: var(--panel-slate);
  border: 1px solid var(--border-slate);
  border-radius: var(--radius-xl);
  padding: 2.2rem 2rem;
  margin-top: 2rem;
}

.metric-item {
  border-right: 1px solid var(--border-slate);
  padding-right: 1.5rem;
}

.metric-item:last-child {
  border-right: none;
  padding-right: 0;
}

.metric-num {
  font-size: 2.4rem;
  font-family: var(--font-sans);
  font-weight: 800;
  color: var(--lime);
  line-height: 1.1;
  margin-bottom: 0.3rem;
}

.metric-label {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

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

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2.5rem;
}

.planar-card {
  background: var(--panel-slate);
  border: 1px solid var(--border-slate);
  border-radius: var(--radius-xl);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color 0.25s ease;
}

.planar-card:hover {
  border-color: var(--lime);
}

.planar-card h3 {
  font-size: 1.4rem;
  margin: 0.5rem 0 1rem;
  color: var(--text-pure);
}

.planar-card p {
  font-size: 0.98rem;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.card-link {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--lime);
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.card-link:hover {
  color: var(--lime-hover);
  text-decoration: underline;
}

.card-image-wrap {
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 1.25rem;
  border: 1px solid var(--border-slate);
}

.card-image-wrap img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
}

/* Tabs Spatial Module */
.tabs-module {
  background: var(--panel-slate);
  border: 1px solid var(--border-slate);
  border-radius: var(--radius-xl);
  overflow: hidden;
  margin: 2.5rem 0;
}

.tab-nav {
  display: flex;
  background: var(--surface-slate);
  border-bottom: 1px solid var(--border-slate);
}

.tab-btn {
  background: transparent;
  border: none;
  color: var(--text-dim);
  padding: 1.2rem 2rem;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: all 0.2s ease;
  border-right: 1px solid var(--border-slate);
}

.tab-btn.active {
  background: var(--panel-slate);
  color: var(--lime);
}

.tab-content-panel {
  display: none;
  padding: 2.5rem;
}

.tab-content-panel.active {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: center;
}

/* Simulator Form Tool */
.simulator-box {
  background: var(--surface-slate);
  border: 1px solid var(--border-slate);
  border-radius: var(--radius-xl);
  padding: 2.5rem;
  margin: 3rem 0;
}

.simulator-box h3 {
  font-size: 1.75rem;
  margin-bottom: 0.5rem;
}

.simulator-box p.desc {
  margin-bottom: 2rem;
  color: var(--text-dim);
}

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

.input-field label {
  display: block;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.input-field input,
.input-field select {
  width: 100%;
  padding: 0.85rem 1rem;
  background: var(--bg-slate);
  border: 1px solid var(--border-slate);
  border-radius: var(--radius-md);
  color: var(--text-pure);
  font-size: 1rem;
  font-family: var(--font-sans);
}

.input-field input:focus,
.input-field select:focus {
  outline: none;
  border-color: var(--lime);
}

.sim-output {
  background: var(--bg-slate);
  border: 1px solid var(--lime);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.output-unit h4 {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 0.3rem;
}

.output-value {
  font-size: 1.8rem;
  font-weight: 700;
  font-family: var(--font-sans);
  color: var(--lime);
}

/* Colophon & Footer */
footer.site-footer {
  background: #0f141c;
  border-top: 1px solid var(--border-slate);
  padding: 4.5rem 0 2.5rem;
  margin-top: 5rem;
  font-size: 0.95rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1.2fr;
  gap: 3rem;
  margin-bottom: 3.5rem;
}

.colophon-desc {
  font-size: 0.9rem;
  color: var(--text-dim);
  line-height: 1.6;
}

.footer-col h4 {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-pure);
  margin-bottom: 1.25rem;
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 0.75rem;
}

.footer-col ul li a {
  color: var(--text-dim);
  font-size: 0.9rem;
}

.footer-col ul li a:hover {
  color: var(--lime);
}

.footer-bottom {
  border-top: 1px solid var(--border-slate);
  padding-top: 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  color: var(--text-dim);
  font-size: 0.85rem;
  font-family: var(--font-sans);
}

.legal-inline {
  display: flex;
  gap: 1.5rem;
}

.legal-inline a {
  color: var(--text-dim);
}

.legal-inline a:hover {
  color: var(--lime);
}

/* Responsive adjustments */
@media (max-width: 1024px) {
  .hero-split {
    grid-template-columns: 1fr;
  }
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }
  nav.main-nav {
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
  .hero-content h1 {
    font-size: 2.2rem;
  }
  .grid-3, .grid-2 {
    grid-template-columns: 1fr;
  }
  .metric-ribbon {
    grid-template-columns: repeat(2, 1fr);
  }
  .metric-item:nth-child(2) {
    border-right: none;
  }
  .tab-content-panel.active {
    grid-template-columns: 1fr;
  }
  .sim-grid {
    grid-template-columns: 1fr;
  }
  .sim-output {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce){*,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important;scroll-behavior:auto!important}}