/* Стили для landing page на Bootstrap */

/* CSS переменные для цветовой схемы */
:root {
  /* Основные цвета */
  --primary-50: #eff6ff;
  --primary-100: #dbeafe;
  --primary-200: #bfdbfe;
  --primary-300: #93c5fd;
  --primary-400: #60a5fa;
  --primary-500: #3b82f6;
  --primary-600: #2563eb;
  --primary-700: #1d4ed8;
  --primary-800: #1e40af;
  --primary-900: #1e3a8a;
  
  /* Градиенты */
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-hero: linear-gradient(135deg, #2563eb 0%, #1e40af 25%, #1e3a8a 50%, #1d4ed8 75%, #3b82f6 100%);
  --gradient-card: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
  --accent-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --success-gradient: linear-gradient(135deg, #00c9a7 0%, #00a085 100%);
  --warning-gradient: linear-gradient(135deg, #f5ca99 0%, #f1b764 100%);
  --danger-gradient: linear-gradient(135deg, #ff7675 0%, #fd79a8 100%);
  
  /* Тени */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
  --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.5);
  --shadow-colored: 0 10px 25px rgba(59, 130, 246, 0.2);
  --shadow-success: 0 10px 25px rgba(0, 201, 167, 0.2);
  --shadow-warning: 0 10px 25px rgba(245, 202, 153, 0.2);
  --shadow-danger: 0 10px 25px rgba(255, 118, 117, 0.2);
  
  /* Анимации */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* Радиусы */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* Z-index layers */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  --z-toast: 1080;
  
  /* Дополнительные цвета */
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
}

@media (prefers-color-scheme: dark) {
  :root {
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
  }
}


/* ===== KAGGLE-STYLE HERO SECTION ===== */
.kaggle-hero-section {
  padding: 7rem 0 6rem;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
}

/* Background decoration elements */
.kaggle-hero-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(102, 126, 234, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.kaggle-hero-section::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(118, 75, 162, 0.06) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

/* Left side - Main content */
.hero-main-content {
  max-width: 580px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(102, 126, 234, 0.1);
  border: 1px solid rgba(102, 126, 234, 0.2);
  border-radius: 20px;
  color: #667eea;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 24px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  backdrop-filter: blur(20px);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background: #10b981;
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
  box-shadow: 0 0 10px rgba(16, 185, 129, 0.5);
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.7;
    transform: scale(1.2);
  }
}

.badge-shine {
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  animation: shine 3s ease-in-out infinite;
}

@keyframes shine {
  0% {
    left: -100%;
  }
  100% {
    left: 100%;
  }
}

.kaggle-hero-title {
  font-size: clamp(2.5rem, 5vw, 3.8rem);
  font-weight: 800;
  line-height: 1.15;
  color: #0f172a;
  margin-bottom: 24px;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  letter-spacing: -0.02em;
}

.gradient-text {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f59e0b 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  background-size: 300% 300%;
  animation: gradientText 4s ease-in-out infinite;
  position: relative;
}

@keyframes gradientText {
  0%, 100% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
}

.kaggle-hero-description {
  font-size: 1.125rem;
  line-height: 1.6;
  color: #6b7280;
  margin-bottom: 32px;
  max-width: 480px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

/* Bootstrap button overrides */
.btn-kaggle-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border-radius: 0.625rem;
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.35);
  position: relative;
  overflow: hidden;
  letter-spacing: 0.3px;
}

.btn-kaggle-primary::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s ease;
}

.btn-kaggle-primary:hover {
  background: linear-gradient(135deg, #5a6fd8 0%, #6a4190 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5);
  color: white;
  text-decoration: none;
}

.btn-kaggle-primary:hover::before {
  left: 100%;
}

.btn-kaggle-primary:focus-visible {
  outline: 2px solid #667eea;
  outline-offset: 2px;
  box-shadow: 0 0 0 0.25rem rgba(102, 126, 234, 0.25);
}

.btn-kaggle-secondary {
  display: inline-flex;
  align-items: center;
  padding: 0.875rem 1.75rem;
  background: white;
  color: #667eea;
  border: 2px solid #667eea;
  border-radius: 0.625rem;
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all 0.3s ease;
  letter-spacing: 0.3px;
}

.btn-kaggle-secondary:hover {
  background: #667eea;
  border-color: #667eea;
  color: white;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.btn-kaggle-secondary:focus-visible {
  outline: 2px solid #667eea;
  outline-offset: 2px;
  box-shadow: 0 0 0 0.25rem rgba(102, 126, 234, 0.25);
}

/* Stats section */
.kaggle-stats {
  display: flex;
  gap: 32px;
  padding-top: 24px;
  border-top: 1px solid #e5e7eb;
}

.kaggle-stats .stat-item {
  text-align: left;
}

.kaggle-stats .stat-number {
  font-size: 28px;
  font-weight: 700;
  color: #1f2937;
  line-height: 1.2;
}

.kaggle-stats .stat-label {
  font-size: 14px;
  color: #6b7280;
  margin-top: 4px;
}

/* Right side - Visual elements */
.hero-visual {
  position: relative;
  height: 480px;
}

/* ===== PAGE BACKGROUND ===== */
.bg-light {
  background: linear-gradient(180deg, #f9fafb 0%, #f3f4f6 50%, #fff 100%);
}

section {
  position: relative;
  z-index: 1;
}

/* Kaggle cards */
.kaggle-card {
  background: white;
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  border: 1px solid #e5e7eb;
  position: absolute;
  max-width: 300px;
  transition: all 0.4s ease;
  backdrop-filter: blur(10px);
}

.kaggle-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
  border-color: #667eea;
}

.dataset-card {
  top: 0;
  left: 0;
  animation: float 6s ease-in-out infinite;
}

.notebook-card {
  top: 120px;
  right: 40px;
  animation: float 6s ease-in-out infinite 2s;
}

.chart-card {
  bottom: 100px;
  left: 20px;
  animation: float 6s ease-in-out infinite 4s;
}

.competition-card {
  bottom: 0;
  right: 0;
  animation: float 6s ease-in-out infinite 1s;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-15px);
  }
}

/* Card styles */
.card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.card-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 600;
}

.card-title h3 {
  font-size: 16px;
  font-weight: 600;
  color: #1f2937;
  margin: 0 0 4px 0;
}

.card-title p {
  font-size: 12px;
  color: #6b7280;
  margin: 0;
}

.card-content p {
  font-size: 14px;
  color: #4b5563;
  line-height: 1.5;
  margin: 0 0 12px 0;
}

.card-footer {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  padding: 4px 8px;
  background: #f3f4f6;
  color: #6b7280;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 500;
}

.tag-python {
  background: #dbeafe;
  color: #1d4ed8;
}

/* Chart card */
.chart-container {
  text-align: center;
}

.chart-header h4 {
  font-size: 14px;
  font-weight: 600;
  color: #1f2937;
  margin: 0 0 16px 0;
}

.accuracy-circle {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 0;
}

.segment-chart {
  position: relative;
  width: 120px;
  height: 120px;
}

.donut-chart {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.donut-hole {
  fill: #f9fafb;
}

.donut-ring {
  fill: transparent;
}

.donut-segment {
  transition: stroke-width 0.3s ease;
  stroke-linecap: round;
}

.segment-1 {
  animation: segment1Draw 2s ease-out forwards;
  stroke-dasharray: 0 100;
}

.segment-2 {
  animation: segment2Draw 2s ease-out 0.5s forwards;
  stroke-dasharray: 0 100;
}

.segment-3 {
  animation: segment3Draw 2s ease-out 1s forwards;
  stroke-dasharray: 0 100;
}

@keyframes segment1Draw {
  to {
    stroke-dasharray: 70 100;
  }
}

@keyframes segment2Draw {
  to {
    stroke-dasharray: 20 100;
  }
}

@keyframes segment3Draw {
  to {
    stroke-dasharray: 10 100;
  }
}

.chart-legend {
  display: flex;
  gap: 12px;
  margin-top: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: #6b7280;
}

.legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.legend-dot.high {
  background: #667eea;
}

.legend-dot.medium {
  background: #764ba2;
}

.legend-dot.low {
  background: #f59e0b;
}

.chart-footer {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.accuracy-icon {
  color: #667eea;
  margin-bottom: 4px;
}

.accuracy-icon svg {
  animation: accuracyPulse 2s ease-in-out infinite;
}

@keyframes accuracyPulse {
  0%, 100% {
    transform: scale(1);
    opacity: 0.8;
  }
  50% {
    transform: scale(1.1);
    opacity: 1;
  }
}

.chart-value {
  font-size: 18px;
  font-weight: 700;
  color: #1f2937;
  display: block;
}

.chart-label {
  font-size: 12px;
  color: #6b7280;
}

/* Competition card */
.competition-header {
  text-align: center;
  margin-bottom: 12px;
}

.competition-prize {
  font-size: 20px;
  font-weight: 700;
  color: #059669;
  margin-bottom: 4px;
}

.competition-type {
  font-size: 12px;
  color: #6b7280;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.competition-progress {
  margin-top: 12px;
}

.progress-bar {
  width: 100%;
  height: 4px;
  background: #f3f4f6;
  border-radius: 2px;
  overflow: hidden;
  margin-bottom: 8px;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #3b82f6, #1d4ed8);
  border-radius: 2px;
  animation: progressFill 2s ease-out;
}

@keyframes progressFill {
  from {
    width: 0;
  }
}

.progress-text {
  font-size: 12px;
  color: #6b7280;
  text-align: center;
  display: block;
}

/* ===== FEATURES SECTION ===== */
/* Bootstrap overwrites for feature cards */
.feature-card {
  background: white;
  border-radius: 1.5rem;
  padding: 2rem;
  border: 1px solid #e5e7eb;
  transition: all 0.4s ease;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  transform: scaleX(0);
  transition: transform 0.4s ease;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
  border-color: #667eea;
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-card:focus-visible {
  outline: 2px solid #667eea;
  outline-offset: 2px;
}

.feature-icon {
  width: 4rem;
  height: 4rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
  cursor: pointer;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.35);
}

.feature-icon::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  transition: all 0.5s ease;
  transform: translate(-50%, -50%);
}

.feature-card:hover .feature-icon::before {
  width: 100%;
  height: 100%;
}

.feature-icon svg {
  width: 1.75rem;
  height: 1.75rem;
  color: white;
  position: relative;
  z-index: 1;
  font-weight: bold;
}

/* ===== CTA SECTION ===== */
.cta-section {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 1.5rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 8px 30px rgba(102, 126, 234, 0.35);
  transition: all 0.4s ease;
}

.cta-section:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 40px rgba(102, 126, 234, 0.45);
}

.cta-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.15) 0%, transparent 60%),
    radial-gradient(circle at 70% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 60%);
  pointer-events: none;
}

/* ===== SECTION HEADERS ===== */
section h2, 
.feature-card h3 {
  color: #0f172a;
  font-weight: 800;
  letter-spacing: -0.02em;
}

section h2 {
  font-size: clamp(1.875rem, 5vw, 2.5rem);
  margin-bottom: 1.5rem;
}

.feature-card h3 {
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

section p,
.feature-card p {
  color: #6b7280;
  line-height: 1.6;
  font-size: 1rem;
}

/* ===== UTILITY CLASSES ===== */
.text-balance {
  text-wrap: balance;
}

.content-visibility-auto {
  content-visibility: auto;
}

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

.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: #000;
  color: #fff;
  padding: 8px;
  text-decoration: none;
  z-index: 100;
}

.skip-link:focus {
  top: 6px;
}

.modern-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 1rem;
}

.section-header {
  margin-bottom: 3rem;
  text-align: center;
}

.section-header h2 {
  margin-bottom: 1rem;
}

.section-header p {
  max-width: 600px;
  margin: 0 auto;
  color: #64748b;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes fadeInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes optimized-fade-in {
  from {
    opacity: 0;
    transform: translate3d(0, 30px, 0);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.8s ease forwards;
}

.animate-fade-in-left {
  animation: fadeInLeft 0.8s ease forwards;
}

.animate-fade-in-right {
  animation: fadeInRight 0.8s ease forwards;
}

.performance-fade-in {
  animation: optimized-fade-in 0.6s ease-out forwards;
  will-change: transform, opacity;
}

/* ===== NEURAL NETWORK BACKGROUND ===== */
.neural-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0.3;
  pointer-events: none;
}

.neural-node {
  filter: drop-shadow(0 0 6px rgba(255, 255, 255, 0.8));
}

.neural-symbol {
  text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
  font-weight: 300;
}

.ml-nodes {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
}

.neural-node {
  position: absolute;
  width: 4px;
  height: 4px;
  background: rgba(59, 130, 246, 0.6);
  border-radius: 50%;
  box-shadow: 0 1px 3px rgba(59, 130, 246, 0.3);
  animation: gentlePulse 4s ease-in-out infinite;
}

.neural-node:nth-child(1) { top: 25%; left: 20%; animation-delay: 0s; }
.neural-node:nth-child(2) { top: 40%; left: 75%; animation-delay: 1s; background: rgba(16, 185, 129, 0.6); box-shadow: 0 1px 3px rgba(16, 185, 129, 0.3); }
.neural-node:nth-child(3) { top: 65%; left: 30%; animation-delay: 2s; background: rgba(139, 92, 246, 0.6); box-shadow: 0 1px 3px rgba(139, 92, 246, 0.3); }
.neural-node:nth-child(4) { top: 80%; left: 70%; animation-delay: 3s; }
.neural-node:nth-child(5) { top: 35%; left: 50%; animation-delay: 1.5s; background: rgba(16, 185, 129, 0.6); box-shadow: 0 1px 3px rgba(16, 185, 129, 0.3); }
.neural-node:nth-child(6) { top: 15%; left: 85%; animation-delay: 2.5s; background: rgba(139, 92, 246, 0.6); box-shadow: 0 1px 3px rgba(139, 92, 246, 0.3); }

@keyframes gentlePulse {
  0%, 100% {
    opacity: 0.4;
    transform: scale(1);
  }
  50% {
    opacity: 0.8;
    transform: scale(1.2);
  }
}

.neural-connections {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.connection-line {
  position: absolute;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.15), transparent);
  transform-origin: left center;
  animation: subtleFlow 6s ease-in-out infinite;
}

.connection-line:nth-child(1) {
  top: 25%;
  left: 20%;
  width: 55%;
  transform: rotate(20deg);
  animation-delay: 0s;
}

.connection-line:nth-child(2) {
  top: 40%;
  left: 30%;
  width: 45%;
  transform: rotate(-15deg);
  animation-delay: 2s;
  background: linear-gradient(90deg, transparent, rgba(16, 185, 129, 0.15), transparent);
}

.connection-line:nth-child(3) {
  top: 65%;
  left: 50%;
  width: 30%;
  transform: rotate(35deg);
  animation-delay: 4s;
  background: linear-gradient(90deg, transparent, rgba(139, 92, 246, 0.15), transparent);
}

@keyframes subtleFlow {
  0%, 100% {
    opacity: 0.2;
  }
  50% {
    opacity: 0.5;
  }
}

/* ===== RESPONSIVE STYLES ===== */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
    text-align: center;
  }
  
  .hero-visual {
    height: 400px;
    margin: 0 auto;
    max-width: 500px;
  }
  
  .kaggle-stats {
    justify-content: center;
  }
}

@media (min-width: 768px) and (max-width: 1024px) and (orientation: portrait) {
  .hero-grid {
    gap: 2rem;
  }
  
  .feature-card {
    padding: 1.75rem;
  }
}

@media (min-width: 1400px) {
  .kaggle-hero-title {
    font-size: 4rem;
  }
  
  .kaggle-hero-description {
    font-size: 1.25rem;
  }
  
  .feature-card {
    padding: 2.5rem;
  }
  
  .stat-number {
    font-size: 3.5rem;
  }
}

@media (max-width: 768px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  
  .hero-visual {
    height: 300px;
    max-width: 100%;
  }
  
  .kaggle-hero-title {
    font-size: 2rem;
    margin-bottom: 1rem;
  }
  
  .kaggle-hero-description {
    font-size: 1rem;
    margin-bottom: 1.5rem;
  }
  
  .hero-actions {
    flex-direction: column;
    gap: 1rem;
  }
  
  .btn-kaggle-primary,
  .btn-kaggle-secondary {
    width: 100%;
    justify-content: center;
  }
  
  .kaggle-stats {
    flex-direction: column;
    gap: 1rem;
  }
  
  .kaggle-card {
    position: relative;
    margin-bottom: 1rem;
    top: auto;
    left: auto;
    right: auto;
    bottom: auto;
    animation: none;
  }
  
  .feature-card {
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .kaggle-hero-section {
    padding: 3rem 0 2rem;
  }
  
  .kaggle-hero-title {
    font-size: 1.75rem;
  }
  
  .hero-badge {
    padding: 0.5rem 1rem;
    font-size: 0.8rem;
    margin-bottom: 1rem;
  }
  
  .kaggle-stats {
    gap: 0.5rem;
  }
  
  .kaggle-stats .stat-number {
    font-size: 1.5rem;
  }
  
  .kaggle-stats .stat-label {
    font-size: 12px;
  }
  
  .btn-kaggle-primary,
  .btn-kaggle-secondary {
    padding: 10px 16px;
    font-size: 14px;
  }
}

@media (max-width: 320px) {
  .kaggle-hero-title {
    font-size: 1.5rem;
    line-height: 1.2;
  }
  
  .kaggle-hero-description {
    font-size: 0.9rem;
  }
  
  .btn-kaggle-primary,
  .btn-kaggle-secondary {
    padding: 8px 12px;
    font-size: 12px;
  }
  
  .feature-card {
    padding: 1rem;
  }
  
  .feature-icon {
    width: 3rem;
    height: 3rem;
  }
}

@media (min-height: 900px) {
  .kaggle-hero-section {
    min-height: 90vh;
  }
}

/* Hover эффекты только для устройств с pointer */
@media (hover: hover) and (pointer: fine) {
  .feature-card {
    cursor: pointer;
  }
  
  .feature-card:hover .feature-icon {
    transform: scale(1.1) rotate(5deg);
  }
}

/* Специальные стили для устройств с сенсорным управлением */
@media (hover: none) and (pointer: coarse) {
  .btn-kaggle-primary,
  .btn-kaggle-secondary {
    min-height: 48px;
  }
  
  .feature-card {
    transition: none;
  }
  
  .interactive-icon {
    min-width: 44px;
    min-height: 44px;
  }
}

/* Улучшенные фокус состояния для accessibility */
.btn-kaggle-primary:focus-visible,
.btn-kaggle-secondary:focus-visible {
  outline: 2px solid #3b82f6;
  outline-offset: 2px;
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.1);
}

.feature-card:focus-visible {
  outline: 2px solid #3b82f6;
  outline-offset: 2px;
}

/* Контрастные варианты для лучшей доступности */
.high-contrast .btn-kaggle-primary {
  background: #000;
  color: #fff;
  border: 2px solid #fff;
}

.high-contrast .btn-kaggle-secondary {
  background: #fff;
  color: #000;
  border: 2px solid #000;
}

.high-contrast .feature-card {
  border: 2px solid #000;
  background: #fff;
}

/* Улучшения для печати */
@media print {
  .kaggle-hero-section,
  .btn-kaggle-primary,
  .btn-kaggle-secondary,
  .cta-section {
    background: none !important;
    color: #000 !important;
    box-shadow: none !important;
  }
  
  .neural-background,
  .hero-particles {
    display: none !important;
  }
}

/* Специальные стили для браузеров Safari */
@supports (-webkit-appearance: none) {
  .kaggle-hero-section {
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
  }
  
  .feature-card {
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
  }
}

/* Оптимизация производительности */
.kaggle-hero-section,
.feature-card,
.stat-item,
.cta-section {
  contain: layout style paint;
}

/* Специальные стили для режима экономии трафика */
@media (prefers-reduced-data: reduce) {
  .kaggle-hero-section::before,
  .neural-background,
  .hero-particles {
    display: none;
  }
  
  .feature-card::before {
    display: none;
  }
}

/* Scroll snap для плавной навигации */
.scroll-section {
  scroll-snap-align: start;
}

html {
  scroll-snap-type: y proximity;
}

/* Code font styles */
.code-font {
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-variant-ligatures: none;
}

/* Специальные стили для старых браузеров IE11 */
@media screen and (-ms-high-contrast: active), screen and (-ms-high-contrast: none) {
  .kaggle-hero-section {
    background: #2563eb;
  }
  
  .feature-card {
    background: #ffffff;
    border: 1px solid #e2e8f0;
  }
  
  .btn-kaggle-primary {
    background: #667eea;
  }
  
  .btn-kaggle-secondary {
    background: transparent;
    border: 2px solid #667eea;
  }
}

/* Modern Landing Styles */
.modern-landing {
  background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
  min-height: 100vh;
}

.compact-header {
  background: linear-gradient(135deg, rgba(255,255,255,0.95) 0%, rgba(249,250,251,0.95) 100%);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(229, 231, 235, 0.3);
}

/* Grid utilities */
.modern-grid {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

@media (min-width: 768px) {
  .modern-grid {
    gap: 3rem;
  }
}

@media (min-width: 640px) {
  .modern-container {
    padding: 0 2rem;
  }
}

@media (min-width: 1024px) {
  .modern-container {
    padding: 0 3rem;
  }
}

/* ========== Contact Page Styles ========== */

.contact-hero {
  background: transparent;
  padding: 5rem 0;
}

.contact-card {
  transition: all 0.3s ease;
  border: 1px solid #e7eaf3;
  background: linear-gradient(135deg, #ffffff 0%, #f8f9fb 100%);
}

.contact-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(102, 126, 234, 0.12);
  border-color: #667eea;
}

.contact-icon {
  width: 3.5rem;
  height: 3.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
  color: #667eea;
  font-size: 1.5rem;
}

.form-group-wrapper {
  margin-bottom: 1.5rem;
}

.form-control {
  border: 1px solid #e7eaf3;
  background: #ffffff;
  padding: 0.75rem 1rem;
  transition: all 0.3s ease;
}

.form-control:focus {
  border-color: #667eea;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
  background: #ffffff;
}

.form-label {
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 0.5rem;
  font-size: 0.95rem;
}

.btn-submit {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  color: white;
  font-weight: 600;
  padding: 0.875rem 2rem;
  border-radius: 0.5rem;
  transition: all 0.3s ease;
}

.btn-submit:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(102, 126, 234, 0.3);
  color: white;
}

.btn-submit:active {
  transform: translateY(0);
}

.contact-methods {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
}

.map-container {
  border-radius: 0.5rem;
  overflow: hidden;
  border: 1px solid #e7eaf3;
  height: 400px;
}

.map-container iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: #f0f1f7;
  color: #667eea;
  transition: all 0.3s ease;
  text-decoration: none;
}

.social-links a:hover {
  background: #667eea;
  color: white;
  transform: translateY(-2px);
}

.contact-info-badge {
  display: inline-block;
  background: #f0f1f7;
  padding: 0.75rem 1.5rem;
  border-radius: 2rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: #667eea;
}

@media (max-width: 768px) {
  .contact-hero {
    padding: 3rem 0;
  }

  .map-container {
    height: 300px;
  }
}