/* ===== CSS CUSTOM PROPERTIES ===== */
:root {
  /* Color System */
  --primary-700: #003366;
  --primary-500: #005A9C;
  --primary-100: #E6F0F7;
  
  --neutral-900: #111827;
  --neutral-600: #4B5563;
  --neutral-200: #E5E7EB;
  --neutral-100: #F3F4F6;
  --neutral-0: #FFFFFF;
  
  --success: #10B981;
  --warning: #F59E0B;
  --error: #EF4444;

  /* Typography */
  --font-heading: 'Poppins', sans-serif;
  --font-body: 'Inter', sans-serif;

  /* Spacing (8px base) */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 32px;
  --space-xl: 48px;
  --space-xxl: 64px;
  --space-xxxl: 96px;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  /* Shadows */
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.08);

  /* Max Width */
  --max-width: 1280px;
}

/* ===== RESET & BASE STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  padding-top: 70px; /* Space for sticky header */
  font-size: 16px;
  line-height: 1.6;
  color: var(--neutral-900);
  background-color: var(--neutral-100);
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-sm);
}

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

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

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4 {
  font-family: var(--font-heading);
  line-height: 1.2;
  margin-bottom: var(--space-sm);
}

h1 {
  font-size: 48px;
  font-weight: 700;
  color: var(--primary-700);
}

h2 {
  font-size: 32px;
  font-weight: 600;
  color: var(--primary-700);
}

h3 {
  font-size: 24px;
  font-weight: 500;
  color: var(--primary-700);
}

h4 {
  font-size: 18px;
  font-weight: 600;
  color: var(--neutral-900);
}

p {
  margin-bottom: var(--space-sm);
  line-height: 1.6;
}

sup {
  font-size: 0.75em;
}

/* ===== ICONS ===== */
.icon {
  width: 24px;
  height: 24px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  flex-shrink: 0;
}

.btn-icon {
  width: 20px;
  height: 20px;
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  height: 48px;
  padding: 0 var(--space-md);
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 500;
  cursor: pointer;
  transition: all 250ms ease-out;
  text-decoration: none;
}

.btn-primary {
  background-color: var(--primary-700);
  color: var(--neutral-0);
}

.btn-primary:hover {
  background-color: var(--primary-500);
  transform: translateY(-2px);
}

.btn-secondary {
  background-color: var(--neutral-0);
  color: var(--primary-700);
  border: 1px solid var(--neutral-200);
}

.btn-secondary:hover {
  background-color: var(--primary-100);
}

/* ===== SECTIONS ===== */
section {
  padding: var(--space-xxxl) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.section-underline {
  width: 60px;
  height: 3px;
  background-color: var(--primary-700);
  margin: var(--space-sm) auto 0;
}

/* ===== HEADER & NAVIGATION ===== */
.main-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-md);
  z-index: 1000;
  height: 70px;
}

.main-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 100%;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 20px;
  color: var(--neutral-900);
}

.nav-links {
  display: flex;
  gap: var(--space-md);
  list-style: none;
}

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--neutral-600);
  padding: var(--space-xs) 0;
  position: relative;
  transition: color 200ms ease;
}

.nav-link:hover {
  color: var(--primary-700);
}

.nav-link.active {
  color: var(--primary-700);
  font-weight: 600;
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--primary-700);
}

/* ===== HERO SECTION ===== */
.hero {
  background-color: var(--neutral-0);
  padding: var(--space-xxxl) 0;
  text-align: center;
}

.hero-content {
  max-width: 900px;
  margin: 0 auto;
}

.university-header {
  margin-bottom: var(--space-lg);
}

.logos-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
  margin: 0 auto var(--space-sm);
}

.university-logo {
  height: 80px;
}

.nav-logo {
  height: 45px;
  width: auto;
}

.event-logo {
  height: 240px;
  max-width: 480px;
  object-fit: contain;
}

.emblem-icon {
  font-size: 36px;
}

.university-name {
  font-size: 18px;
  font-weight: 600;
  color: var(--primary-700);
  margin-bottom: var(--space-xs);
}

.ministry {
  font-size: 14px;
  color: var(--neutral-600);
  font-style: italic;
  margin-bottom: var(--space-xs);
}

.event-title {
  margin-bottom: var(--space-sm);
  line-height: 1.2;
}

.event-subtitle {
  margin-bottom: var(--space-lg);
}

.event-code {
  display: inline-block;
  background-color: var(--primary-100);
  color: var(--primary-700);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-md);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 18px;
}

.event-details {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  text-align: left;
}

.detail-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
}

.detail-item .icon {
  color: var(--primary-700);
  margin-top: 2px;
}

.detail-item strong {
  display: block;
  color: var(--neutral-900);
  margin-bottom: var(--space-xs);
}

.detail-item p {
  color: var(--neutral-600);
  margin: 0;
  font-size: 14px;
}

.hero-buttons {
  display: flex;
  gap: var(--space-sm);
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
}

.event-leaders {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-md);
  text-align: left;
  padding: var(--space-lg);
  background-color: var(--neutral-100);
  border-radius: var(--radius-lg);
}

.leader {
  font-size: 14px;
  color: var(--neutral-900);
}

.leaders-group {
  font-size: 14px;
  color: var(--neutral-600);
}

.leaders-group strong {
  display: block;
  color: var(--neutral-900);
  margin-bottom: var(--space-xs);
}

/* ===== OVERVIEW SECTION ===== */
.overview {
  background-color: var(--neutral-0);
}

.overview-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
}

.overview-content {
  font-size: 16px;
  line-height: 1.7;
}

.intro-text {
  font-size: 18px;
  font-weight: 500;
  color: var(--primary-700);
}

.objectives-card {
  background-color: var(--neutral-100);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.objectives-card h3 {
  margin-bottom: var(--space-md);
  text-align: center;
}

.objectives-list {
  list-style: none;
}

.objective-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.objective-item:last-child {
  margin-bottom: 0;
}

.objective-icon {
  color: var(--primary-700);
  margin-top: 2px;
  flex-shrink: 0;
}

.objective-item strong {
  display: block;
  color: var(--neutral-900);
  margin-bottom: var(--space-xs);
}

.objective-item p {
  color: var(--neutral-600);
  margin: 0;
  font-size: 14px;
}

/* ===== TOPICS SECTION ===== */
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-lg);
}

.topic-card {
  background-color: var(--neutral-0);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  text-align: center;
  transition: all 300ms ease-in-out;
}

.topic-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.topic-icon {
  width: 64px;
  height: 64px;
  background-color: var(--primary-100);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
  color: var(--primary-700);
}

.topic-icon .icon {
  width: 32px;
  height: 32px;
}

.topic-card h3 {
  margin-bottom: var(--space-sm);
}

.topic-card p {
  color: var(--neutral-600);
  margin: 0;
}

/* ===== TIMELINE SECTION ===== */
.timeline {
  background-color: var(--neutral-0);
}

.timeline-container {
  max-width: 600px;
  margin: 0 auto;
  position: relative;
}

.timeline-container::before {
  content: '';
  position: absolute;
  left: 20px;
  top: 0;
  bottom: 0;
  width: 1px;
  background-color: var(--neutral-200);
}

.timeline-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  position: relative;
}

.timeline-item:last-child {
  margin-bottom: 0;
}

.timeline-dot {
  width: 16px;
  height: 16px;
  background-color: var(--primary-700);
  border-radius: 50%;
  border: 4px solid var(--neutral-0);
  position: absolute;
  left: 12px;
  z-index: 1;
}

.timeline-item.urgent .timeline-dot {
  background-color: var(--warning);
}

.timeline-item.urgent {
  background-color: var(--primary-100);
  padding: var(--space-md);
  border-radius: var(--radius-lg);
  margin-left: 0;
}

.timeline-content {
  flex: 1;
  padding-left: var(--space-xl);
}

.timeline-item.urgent .timeline-content {
  padding-left: 0;
}

.timeline-date {
  font-size: 16px;
  font-weight: 600;
  color: var(--primary-700);
  margin-bottom: var(--space-xs);
}

.timeline-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--neutral-900);
  margin-bottom: var(--space-xs);
}

.timeline-description {
  color: var(--neutral-600);
  margin: 0;
  font-size: 14px;
}

/* ===== GUIDELINES SECTION ===== */
.guidelines-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-lg);
}

.guideline-card {
  background-color: var(--neutral-0);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  text-align: center;
}

.guideline-icon {
  width: 48px;
  height: 48px;
  background-color: var(--primary-100);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
  color: var(--primary-700);
}

.guideline-card h3 {
  margin-bottom: var(--space-sm);
}

.languages {
  display: flex;
  gap: var(--space-xs);
  justify-content: center;
  flex-wrap: wrap;
  margin-top: var(--space-sm);
}

.language-tag {
  background-color: var(--primary-100);
  color: var(--primary-700);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
}

.format-list {
  text-align: left;
  list-style: none;
  margin: 0;
}

.format-list li {
  margin-bottom: var(--space-xs);
  font-size: 14px;
}

.format-list li:last-child {
  margin-bottom: 0;
}

.email-container {
  margin-top: var(--space-sm);
}

.email-link {
  color: var(--primary-700);
  font-weight: 600;
  font-size: 16px;
  word-break: break-all;
}

.email-link:hover {
  color: var(--primary-500);
}

.pricing-highlight {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: var(--space-xs);
  margin: var(--space-sm) 0;
}

.price {
  font-size: 48px;
  font-weight: 700;
  color: var(--success);
  line-height: 1;
}

.price-note {
  font-size: 14px;
  color: var(--neutral-600);
}

.pricing-description {
  font-size: 14px;
  color: var(--neutral-600);
  margin: 0;
}

/* ===== PUBLICATION SECTION ===== */
.publication {
  background-color: var(--neutral-0);
}

.publication-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.publication-intro {
  font-size: 18px;
  margin-bottom: var(--space-lg);
}

.journal-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-lg);
}

.journal-card {
  background-color: var(--neutral-100);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  text-align: center;
}

.journal-icon {
  width: 48px;
  height: 48px;
  background-color: var(--primary-700);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
  color: var(--neutral-0);
}

.journal-card h3 {
  margin-bottom: var(--space-xs);
  font-size: 18px;
}

.journal-card p {
  color: var(--neutral-600);
  margin: 0;
  font-size: 14px;
}

/* ===== COMMITTEES SECTION ===== */
.committees-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: var(--space-lg);
}

.committee-section {
  background-color: var(--neutral-0);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.committee-section h3 {
  text-align: center;
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--primary-100);
}

.committee-president {
  text-align: center;
  margin-bottom: var(--space-md);
  padding: var(--space-sm);
  background-color: var(--primary-100);
  border-radius: var(--radius-md);
  font-size: 14px;
}

.committee-members {
  display: grid;
  gap: var(--space-xs);
}

.member-item {
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--neutral-100);
  border-radius: var(--radius-sm);
  font-size: 14px;
  transition: background-color 200ms ease;
}

.member-item:hover {
  background-color: var(--primary-100);
}

/* ===== CONTACT SECTION ===== */
.contact {
  background-color: var(--neutral-0);
}

.contact-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-lg);
}

.contact-card {
  background-color: var(--neutral-100);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  text-align: center;
}

.contact-icon {
  width: 48px;
  height: 48px;
  background-color: var(--primary-700);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
  color: var(--neutral-0);
}

.contact-card h3 {
  margin-bottom: var(--space-sm);
}

.contact-email {
  display: inline-block;
  color: var(--primary-700);
  font-weight: 600;
  font-size: 16px;
  margin-top: var(--space-sm);
}

.contact-email:hover {
  color: var(--primary-500);
}

.contact-languages {
  display: flex;
  gap: var(--space-xs);
  justify-content: center;
  flex-wrap: wrap;
  margin-top: var(--space-sm);
}

/* ===== FOOTER ===== */
.footer {
  background-color: var(--primary-700);
  color: var(--neutral-0);
  padding: var(--space-lg) 0;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-logo h4 {
  color: var(--neutral-0);
  margin-bottom: var(--space-xs);
}

.footer-logo p {
  color: var(--primary-100);
  margin: 0;
  font-size: 14px;
}

.footer-links {
  text-align: right;
}

.footer-links p {
  margin: 0;
  font-size: 14px;
  color: var(--primary-100);
}

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

/* Tablet */
@media (max-width: 768px) {
  :root {
    --space-xxxl: 64px;
  }

  h1 {
    font-size: 36px;
  }

  h2 {
    font-size: 28px;
  }

  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 300px;
  }

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

  .overview-grid {
    gap: var(--space-md);
  }

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

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

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

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

  .contact-content {
    grid-template-columns: 1fr;
  }

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

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

  .timeline-container {
    margin-left: var(--space-sm);
  }

  .timeline-item {
    margin-left: 0;
  }

  .timeline-content {
    padding-left: var(--space-md);
  }
}

/* Mobile */
@media (max-width: 480px) {
  .container {
    padding: 0 var(--space-sm);
  }

  h1 {
    font-size: 28px;
  }

  h2 {
    font-size: 24px;
  }

  .event-details {
    grid-template-columns: 1fr;
  }

  .detail-item {
    text-align: center;
    flex-direction: column;
    align-items: center;
  }

  .hero-buttons {
    gap: var(--space-xs);
  }

  .btn {
    height: 44px;
    font-size: 14px;
  }

  .main-nav {
    justify-content: center;
  }

  .nav-links {
    display: none; /* Hide nav links on very small screens, can be replaced with a hamburger menu */
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .topic-card:hover {
    transform: none;
  }

  .btn:hover {
    transform: none;
  }
}