:root {
  --bg: #070b14;
  --surface: #0f1724;
  --text: #f8fafc;
  --muted: #94a3b8;
  --accent: #60a5fa;
  --accent-dark: #3b82f6;
  --border: rgba(148, 163, 184, 0.18);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
  font-family: Inter, system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
}

body {
  line-height: 1.8;
}

.container {
  width: min(1100px, calc(100% - 3rem));
  margin: 0 auto;
}

.site-header {
  padding: 2rem 0 3rem;
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding-bottom: 2rem;
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.brand-flag {
  text-transform: uppercase;
  color: var(--accent);
  letter-spacing: 0.25em;
  font-size: 0.75rem;
}

.brand-name {
  font-size: 1rem;
  color: var(--muted);
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--text);
}

.hero-panel {
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.9), rgba(15, 23, 42, 0.75)), url('') center/cover no-repeat;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: 2rem;
  padding: 4rem 3rem;
  box-shadow: 0 40px 120px rgba(15, 23, 42, 0.4);
}

.hero-copy {
  max-width: 760px;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.24em;
  color: var(--accent);
  font-size: 0.8rem;
  margin: 0 0 1.25rem;
}

.hero-copy h1,
.section-intro h2,
.contact-panel h2 {
  margin: 0;
  font-size: clamp(2.8rem, 5vw, 4.2rem);
  line-height: 1.02;
}

.hero-text,
.section-intro p,
.contact-panel p {
  margin: 1.5rem 0 0;
  max-width: 720px;
  color: var(--muted);
  font-size: 1rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2.25rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.95rem 1.9rem;
  border-radius: 999px;
  background: var(--accent);
  color: white;
  text-decoration: none;
  font-weight: 600;
  transition: transform 0.2s ease, background 0.2s ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
  background: var(--accent-dark);
}

.button.secondary {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.14);
}

.section {
  padding: 4.5rem 0;
}

.section-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 2.5rem;
  align-items: start;
}

.section-intro .eyebrow {
  margin-bottom: 1rem;
}

.section-intro h2 {
  font-size: clamp(2.5rem, 4vw, 3.5rem);
}

.cards-grid {
  display: grid;
  gap: 1.25rem;
}

.feature-card {
  padding: 1.75rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 1.25rem;
}

.feature-card h3 {
  margin: 0 0 0.75rem;
  font-size: 1.15rem;
}

.feature-card p {
  margin: 0;
  color: var(--muted);
}

.feature-card h4 {
  margin: 1.5rem 0 0.5rem;
  color: var(--accent);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.feature-card ul {
  margin: 0.5rem 0 0;
  padding-left: 1.25rem;
  color: var(--muted);
}

.equation {
  overflow-x: auto;
  margin: 0.75rem 0;
  padding: 0.85rem 1rem;
  background: rgba(0, 0, 0, 0.18);
  border-left: 2px solid var(--accent);
  color: var(--text);
  font-family: Georgia, serif;
  font-size: 1.05rem;
  white-space: nowrap;
}

.methodology-grid {
  grid-template-columns: repeat(3, 1fr);
  margin-top: 2.5rem;
}

.model-comparison {
  margin-top: 3rem;
}

.model-comparison h3 {
  margin: 0;
  font-size: 1.5rem;
}

.model-comparison > p {
  max-width: 720px;
  color: var(--muted);
}

.table-wrap {
  overflow-x: auto;
  margin: 1.5rem 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 560px;
}

th,
td {
  padding: 1rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
}

th {
  color: var(--accent);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

td {
  color: var(--muted);
}

td:first-child {
  color: var(--text);
  font-weight: 600;
}

.section-dark {
  background: #0b1220;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.contact-panel {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 2.5rem;
  align-items: start;
}

.contact-portrait {
  display: none;
  width: min(280px, 100%);
  margin-top: 2rem;
  border-radius: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
  object-fit: cover;
}

#contact:target .contact-portrait {
  display: block;
}

.contact-details {
  display: grid;
  gap: 1rem;
}

.contact-item {
  display: grid;
  gap: 0.35rem;
  padding: 1.25rem 1.5rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 1rem;
}

.contact-item span {
  color: var(--muted);
  font-size: 0.95rem;
}

.contact-item a {
  color: white;
  text-decoration: none;
}

.contact-item a:hover,
.contact-item a:focus-visible {
  text-decoration: underline;
}

.footer {
  padding: 2rem 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-inner {
  display: flex;
  justify-content: center;
}

@media (max-width: 900px) {
  .section-grid,
  .contact-panel,
  .header-top {
    grid-template-columns: 1fr;
  }

  .header-top {
    align-items: flex-start;
  }

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

@media (max-width: 640px) {
  .hero-panel {
    padding: 3rem 1.5rem;
  }

  .hero-copy h1,
  .section-intro h2 {
    font-size: 2.5rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
}