/* ===================================
   MODERN DESIGN SYSTEM
   Hacettepe Nöroloji Derneği
   =================================== */

/* === CSS CUSTOM PROPERTIES === */
:root {
  /* Color System - Modern Medical Theme */
  --color-primary: #6366f1;
  --color-primary-dark: #4f46e5;
  --color-primary-light: #818cf8;
  --color-secondary: #06b6d4;
  --color-accent: #8b5cf6;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-hero: linear-gradient(135deg, rgba(102, 126, 234, 0.9) 0%, rgba(118, 75, 162, 0.9) 100%);
  --gradient-card: linear-gradient(to bottom right, #f8fafc, #f1f5f9);

  /* Neutral Colors */
  --color-white: #ffffff;
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;
  --color-gray-600: #4b5563;
  --color-gray-700: #374151;
  --color-gray-800: #1f2937;
  --color-gray-900: #111827;

  /* Typography */
  --font-primary: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-heading: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;

  /* Font Sizes */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-base: 1rem;     /* 16px */
  --text-lg: 1.125rem;   /* 18px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;   /* 36px */
  --text-5xl: 3rem;      /* 48px */
  --text-6xl: 3.75rem;   /* 60px */

  /* Spacing System (8px base) */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.5rem;    /* 24px */
  --space-6: 2rem;      /* 32px */
  --space-8: 3rem;      /* 48px */
  --space-10: 4rem;     /* 64px */
  --space-12: 6rem;     /* 96px */
  --space-16: 8rem;     /* 128px */

  /* Border Radius */
  --radius-sm: 0.375rem;  /* 6px */
  --radius-md: 0.5rem;    /* 8px */
  --radius-lg: 0.75rem;   /* 12px */
  --radius-xl: 1rem;      /* 16px */
  --radius-2xl: 1.5rem;   /* 24px */
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Container */
  --container-max: 1280px;
  --container-padding: var(--space-4);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-primary);
  color: var(--color-gray-800);
  background-color: var(--color-gray-50);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-gray-900);
  margin-bottom: var(--space-4);
}

h1 { font-size: clamp(var(--text-4xl), 5vw, var(--text-6xl)); }
h2 { font-size: clamp(var(--text-3xl), 4vw, var(--text-5xl)); }
h3 { font-size: clamp(var(--text-2xl), 3vw, var(--text-4xl)); }
h4 { font-size: clamp(var(--text-xl), 2.5vw, var(--text-3xl)); }
h5 { font-size: var(--text-xl); }
h6 { font-size: var(--text-lg); }

p {
  margin-bottom: var(--space-4);
  max-width: 70ch;
}

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

a:hover {
  color: var(--color-primary-dark);
}

/* === NAVIGATION === */
.navbar {
  background: var(--gradient-primary);
  box-shadow: var(--shadow-md);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  padding: var(--space-4) 0;
}

.navbar-brand {
  color: var(--color-white) !important;
  font-weight: 700;
  font-size: var(--text-xl);
  letter-spacing: -0.01em;
  transition: transform var(--transition-fast);
}

.navbar-brand:hover {
  transform: scale(1.02);
  color: var(--color-white) !important;
}

.navbar-nav .nav-link {
  color: rgba(255, 255, 255, 0.9) !important;
  font-weight: 500;
  padding: var(--space-2) var(--space-4) !important;
  margin: 0 var(--space-1);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  position: relative;
}

.navbar-nav .nav-link:hover {
  color: var(--color-white) !important;
  background-color: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

.navbar-nav .nav-link.active {
  background-color: rgba(255, 255, 255, 0.2);
  color: var(--color-white) !important;
}

.navbar-toggler {
  border-color: rgba(255, 255, 255, 0.3);
  padding: var(--space-2);
}

.navbar-toggler:focus {
  box-shadow: 0 0 0 0.25rem rgba(255, 255, 255, 0.25);
}

.navbar-toggler-icon {
  filter: brightness(0) invert(1);
}

/* === HERO/CAROUSEL === */
.carousel {
  position: relative;
  margin-bottom: var(--space-10);
  border-radius: 0;
  overflow: hidden;
}

.carousel-inner {
  border-radius: 0;
}

.carousel-item {
  position: relative;
  height: 70vh;
  min-height: 400px;
  max-height: 700px;
}

.carousel-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.carousel-item::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, rgba(0,0,0,0.1) 0%, rgba(0,0,0,0.4) 100%);
}

.carousel-item-no-blur::after {
  display: none;
}

.carousel-caption {
  position: absolute;
  bottom: 20%;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  text-align: center;
  padding: var(--space-6);
  background: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-xl);
  max-width: 90%;
}

.carousel-caption h1 {
  color: var(--color-white);
  font-size: clamp(var(--text-2xl), 4vw, var(--text-5xl));
  text-shadow: 0 2px 10px rgba(0,0,0,0.3);
  margin-bottom: 0;
  font-weight: 800;
}

.carousel-control-prev,
.carousel-control-next {
  width: 60px;
  height: 60px;
  top: 50%;
  transform: translateY(-50%);
  background-color: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-full);
  opacity: 0.8;
  transition: all var(--transition-base);
}

.carousel-control-prev {
  left: var(--space-4);
}

.carousel-control-next {
  right: var(--space-4);
}

.carousel-control-prev:hover,
.carousel-control-next:hover {
  opacity: 1;
  background-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-50%) scale(1.1);
}

.carousel-indicators {
  bottom: var(--space-6);
}

.carousel-indicators button {
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
  background-color: rgba(255, 255, 255, 0.5);
  border: 2px solid transparent;
  transition: all var(--transition-base);
}

.carousel-indicators button.active {
  background-color: var(--color-white);
  transform: scale(1.2);
}

/* === CONTAINER & SECTIONS === */
.container-custom {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.text-content {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--space-10) var(--space-6);
  background-color: var(--color-white);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--space-10);
}

.text-content h2 {
  color: var(--color-gray-900);
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-4);
  border-bottom: 3px solid var(--color-primary);
  display: inline-block;
}

.text-content p {
  font-size: var(--text-lg);
  line-height: 1.8;
  color: var(--color-gray-700);
}

.text-content a {
  color: var(--color-primary);
  font-weight: 600;
  border-bottom: 2px solid transparent;
  transition: border-color var(--transition-fast);
}

.text-content a:hover {
  border-bottom-color: var(--color-primary);
}

/* === HERO IMAGE === */
.hero-image {
  position: relative;
  margin-bottom: var(--space-10);
  height: 400px;
  overflow: hidden;
  border-radius: 0;
}

.hero-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero-image::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-hero);
  opacity: 0.6;
}

/* === TEAM GRID (Kurullar) === */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-6);
  padding: var(--space-6) 0;
}

.team-member-card {
  background: var(--color-white);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
}

.team-member-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-2xl);
}

.team-member-image {
  position: relative;
  width: 100%;
  aspect-ratio: 4/5;
  overflow: hidden;
  background: var(--gradient-card);
}

.team-member-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.team-member-card:hover .team-member-image img {
  transform: scale(1.05);
}

.team-member-info {
  padding: var(--space-5);
  text-align: center;
}

.team-member-name {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-gray-900);
  margin-bottom: var(--space-2);
}

.team-member-role {
  font-size: var(--text-base);
  color: var(--color-primary);
  font-weight: 600;
  padding: var(--space-2) var(--space-4);
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-md);
  display: inline-block;
}

/* === EVENT CARDS === */
.events-section {
  padding: var(--space-8) 0;
}

.events-section h3 {
  color: var(--color-gray-900);
  margin-bottom: var(--space-6);
  margin-top: var(--space-8);
  padding-left: var(--space-4);
  border-left: 4px solid var(--color-primary);
}

.events-section h3:first-of-type {
  margin-top: 0;
}

.event-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  list-style: none;
  padding: 0;
}

.event-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--color-primary);
  transition: all var(--transition-base);
  display: flex;
  align-items: start;
  gap: var(--space-4);
}

.event-card:hover {
  transform: translateX(8px);
  box-shadow: var(--shadow-lg);
  border-left-color: var(--color-secondary);
}

.event-icon {
  width: 48px;
  height: 48px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.event-icon i {
  color: var(--color-white);
  font-size: var(--text-xl);
}

.event-content {
  flex: 1;
}

.event-content a {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-gray-900);
  line-height: 1.5;
  display: block;
  margin-bottom: var(--space-2);
  transition: color var(--transition-fast);
}

.event-content a:hover {
  color: var(--color-primary);
}

.event-date {
  font-size: var(--text-sm);
  color: var(--color-gray-600);
  font-weight: 500;
}

/* === CONTACT SECTION === */
.contact-card {
  background: var(--gradient-primary);
  color: var(--color-white);
  padding: var(--space-8);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  text-align: center;
  margin: var(--space-8) 0;
}

.contact-card h2 {
  color: var(--color-white);
  margin-bottom: var(--space-6);
}

.contact-email {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  background: rgba(255, 255, 255, 0.2);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-lg);
  font-size: var(--text-xl);
  font-weight: 600;
  color: var(--color-white);
  backdrop-filter: blur(10px);
  transition: all var(--transition-base);
}

.contact-email:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: scale(1.05);
  color: var(--color-white);
}

.contact-email i {
  font-size: var(--text-2xl);
}

/* === DOCUMENT DOWNLOAD === */
.download-card {
  background: var(--gradient-card);
  border: 2px dashed var(--color-gray-300);
  padding: var(--space-8);
  border-radius: var(--radius-xl);
  text-align: center;
  transition: all var(--transition-base);
  margin: var(--space-6) 0;
}

.download-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-lg);
}

.download-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  background: var(--gradient-primary);
  color: var(--color-white) !important;
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-lg);
  font-size: var(--text-lg);
  font-weight: 600;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
}

.download-link:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  color: var(--color-white) !important;
}

.download-link i {
  font-size: var(--text-2xl);
}

/* === FOOTER === */
footer {
  background: var(--gradient-primary);
  color: var(--color-white);
  padding: var(--space-10) var(--space-6);
  margin-top: auto;
  text-align: center;
}

footer p {
  margin-bottom: var(--space-5);
  font-size: var(--text-base);
  opacity: 0.9;
  text-align: center;
  max-width: 100%;
}

.social-icons {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
  flex-wrap: wrap;
}

.social-icons a {
  width: 48px;
  height: 48px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-white);
  font-size: var(--text-xl);
  transition: all var(--transition-base);
  backdrop-filter: blur(10px);
}

.social-icons a:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-4px) scale(1.1);
  box-shadow: var(--shadow-lg);
}

/* === RESPONSIVE DESIGN === */
@media (max-width: 1024px) {
  :root {
    --container-padding: var(--space-5);
  }

  .text-content {
    padding: var(--space-8) var(--space-5);
  }

  .team-grid {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: var(--space-5);
  }
}

@media (max-width: 768px) {
  :root {
    --container-padding: var(--space-4);
  }

  .navbar {
    padding: var(--space-3) 0;
  }

  .carousel-item {
    height: 50vh;
    min-height: 300px;
  }

  .carousel-caption {
    bottom: 10%;
    padding: var(--space-4);
  }

  .carousel-control-prev,
  .carousel-control-next {
    width: 40px;
    height: 40px;
  }

  .text-content {
    padding: var(--space-6) var(--space-4);
    margin-bottom: var(--space-6);
    border-radius: var(--radius-xl);
  }

  .hero-image {
    height: 250px;
    margin-bottom: var(--space-6);
  }

  .team-grid {
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--space-4);
  }

  .event-card {
    flex-direction: column;
    text-align: center;
  }

  .contact-card,
  .download-card {
    padding: var(--space-6) var(--space-4);
  }

  footer {
    padding: var(--space-8) var(--space-4);
  }
}

@media (max-width: 480px) {
  .carousel-item {
    height: 40vh;
    min-height: 250px;
  }

  .team-grid {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .navbar-brand {
    font-size: var(--text-lg);
  }

  .text-content p {
    font-size: var(--text-base);
  }
}

/* === UTILITY CLASSES === */
.mt-8 { margin-top: var(--space-8); }
.mb-8 { margin-bottom: var(--space-8); }
.py-8 { padding-top: var(--space-8); padding-bottom: var(--space-8); }
.text-center { text-align: center; }

/* === ANIMATIONS === */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

/* === ACCESSIBILITY === */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Focus styles for accessibility */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}