/* ===== XLENTUM - Modular Institutional Composition ===== */

:root {
  --primary: #1A2B3C;
  --secondary: #E0E0E0;
  --accent-terra: #B25F4C;
  --accent-green: #6A8A7A;
  --text-dark: #333333;
  --text-light: #FFFFFF;
  --spacing-unit: 16px;
  --container-width: 1200px;
  --section-spacing: 80px;
}

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

html, body {
  font-family: 'Georgia', 'Garamond', serif;
  color: var(--text-dark);
  line-height: 1.6;
  background-color: #FFFFFF;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', sans-serif;
  font-size: 16px;
}

/* ===== CONTAINER & GRID ===== */

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 calc(var(--spacing-unit) * 2);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: calc(var(--spacing-unit) * 2);
}

.col-6 { grid-column: span 6; }
.col-8 { grid-column: span 8; }
.col-4 { grid-column: span 4; }
.col-12 { grid-column: span 12; }

/* ===== HEADER ===== */

header {
  background-color: var(--primary);
  color: var(--text-light);
  padding: calc(var(--spacing-unit) * 2);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 2px;
  font-family: 'Georgia', serif;
}

nav ul {
  display: flex;
  list-style: none;
  gap: calc(var(--spacing-unit) * 3);
}

nav a {
  color: var(--text-light);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s ease;
  border-bottom: 2px solid transparent;
}

nav a:hover,
nav a.active {
  color: var(--accent-terra);
  border-bottom-color: var(--accent-terra);
}

/* ===== TYPOGRAPHY ===== */

h1 {
  font-family: 'Georgia', serif;
  font-size: 52px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: calc(var(--spacing-unit) * 2);
  line-height: 1.2;
}

h2 {
  font-family: 'Georgia', serif;
  font-size: 38px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: calc(var(--spacing-unit) * 1.5);
  margin-top: calc(var(--spacing-unit) * 2);
  line-height: 1.3;
}

h3 {
  font-size: 22px;
  font-weight: 600;
  color: var(--accent-green);
  margin-bottom: calc(var(--spacing-unit) * 1);
  margin-top: calc(var(--spacing-unit) * 1.5);
}

p {
  margin-bottom: calc(var(--spacing-unit) * 1.5);
  line-height: 1.8;
}

a {
  color: var(--accent-terra);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--primary);
  text-decoration: underline;
}

/* ===== HERO SECTION ===== */

.hero {
  background-color: var(--secondary);
  padding: calc(var(--spacing-unit) * 8) calc(var(--spacing-unit) * 2);
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: calc(var(--spacing-unit) * 4);
  align-items: center;
}

.hero-content h1 {
  font-size: 48px;
  margin-bottom: calc(var(--spacing-unit) * 2);
}

.hero-content p {
  font-size: 18px;
  margin-bottom: calc(var(--spacing-unit) * 2);
}

.hero-image {
  width: 100%;
  height: 400px;
  object-fit: cover;
  border-radius: 2px;
}

/* ===== SECTIONS ===== */

section {
  padding: var(--section-spacing) calc(var(--spacing-unit) * 2);
}

.section-alt {
  background-color: var(--secondary);
}

.section-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: calc(var(--spacing-unit) * 4);
  align-items: center;
}

.section-content.reverse {
  direction: rtl;
}

.section-content.reverse > * {
  direction: ltr;
}

.section-image {
  width: 100%;
  height: 350px;
  object-fit: cover;
  border-radius: 2px;
}

/* ===== LISTS ===== */

ul, ol {
  margin-left: calc(var(--spacing-unit) * 2);
  margin-bottom: calc(var(--spacing-unit) * 1.5);
}

li {
  margin-bottom: calc(var(--spacing-unit) * 0.75);
  line-height: 1.8;
}

li::marker {
  color: var(--accent-green);
  font-weight: 600;
}

/* ===== BUTTONS ===== */

.btn {
  display: inline-block;
  padding: calc(var(--spacing-unit) * 0.75) calc(var(--spacing-unit) * 2);
  background-color: var(--primary);
  color: var(--text-light);
  border: none;
  border-radius: 2px;
  font-size: 16px;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.btn:hover {
  background-color: var(--accent-terra);
  transform: none;
  box-shadow: 0 4px 12px rgba(178, 95, 76, 0.2);
}

.btn-secondary {
  background-color: var(--accent-terra);
  color: var(--text-light);
}

.btn-secondary:hover {
  background-color: var(--primary);
}

/* ===== CARDS ===== */

.card {
  background-color: #FFFFFF;
  border: 1px solid var(--secondary);
  padding: calc(var(--spacing-unit) * 2);
  margin-bottom: calc(var(--spacing-unit) * 2);
  transition: all 0.3s ease;
}

.card:hover {
  border-color: var(--accent-terra);
  box-shadow: 0 4px 16px rgba(0,0,0,0.08);
}

.card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  margin-bottom: calc(var(--spacing-unit) * 1.5);
  border-radius: 2px;
}

.card h3 {
  margin-top: 0;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: calc(var(--spacing-unit) * 2);
}

/* ===== FOOTER ===== */

footer {
  background-color: var(--primary);
  color: var(--text-light);
  padding: calc(var(--spacing-unit) * 4) calc(var(--spacing-unit) * 2);
  margin-top: calc(var(--section-spacing) * 1.5);
}

footer .container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: calc(var(--spacing-unit) * 2);
  margin-bottom: calc(var(--spacing-unit) * 3);
}

footer h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: calc(var(--spacing-unit) * 1);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

footer ul {
  list-style: none;
  margin-left: 0;
}

footer a {
  color: var(--secondary);
  transition: color 0.2s ease;
}

footer a:hover {
  color: var(--accent-terra);
}

.footer-bottom {
  border-top: 1px solid rgba(224, 224, 224, 0.2);
  padding-top: calc(var(--spacing-unit) * 2);
  text-align: center;
  font-size: 14px;
}

/* ===== CONTACT FORM ===== */

.form-group {
  margin-bottom: calc(var(--spacing-unit) * 2);
}

.form-group label {
  display: block;
  margin-bottom: calc(var(--spacing-unit) * 0.5);
  font-weight: 600;
  color: var(--primary);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: calc(var(--spacing-unit) * 0.75);
  border: 1px solid var(--secondary);
  border-radius: 2px;
  font-family: inherit;
  font-size: 14px;
  transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent-terra);
  box-shadow: 0 0 0 3px rgba(178, 95, 76, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

/* ===== RESPONSIVE ===== */

@media (max-width: 768px) {
  .grid-12,
  .section-content,
  .cards-grid,
  footer .container,
  header .container {
    grid-template-columns: 1fr;
  }
  
  .col-6, .col-8, .col-4 {
    grid-column: span 12;
  }

  nav ul {
    flex-direction: column;
    gap: calc(var(--spacing-unit) * 1);
  }

  h1 {
    font-size: 36px;
  }

  h2 {
    font-size: 28px;
  }

  .hero {
    padding: calc(var(--spacing-unit) * 4) calc(var(--spacing-unit) * 2);
  }

  .hero-image {
    height: 300px;
  }

  section {
    padding: calc(var(--spacing-unit) * 4) calc(var(--spacing-unit) * 2);
  }

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

/* ===== ACCESSIBILITY ===== */

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

/* ===== UTILITY ===== */

.text-center {
  text-align: center;
}

.mt-4 {
  margin-top: calc(var(--spacing-unit) * 4);
}

.mb-4 {
  margin-bottom: calc(var(--spacing-unit) * 4);
}

.highlight {
  color: var(--accent-terra);
  font-weight: 600;
}