/* ============================================
   iTGid Education Platform - Modern CSS Design
   ============================================ */

/* ============================================
   CSS Custom Properties (Variables)
   ============================================ */
:root {
  /* Primary Colors */
  --primary-color: #4F46E5;
  --primary-hover: #4338CA;
  --primary-light: #EEF2FF;
  --primary-dark: #3730A3;

  /* Secondary Colors */
  --secondary-color: #0EA5E9;
  --secondary-hover: #0284C7;
  --secondary-light: #E0F2FE;

  /* Accent Colors */
  --accent-success: #10B981;
  --accent-success-light: #D1FAE5;
  --accent-warning: #F59E0B;
  --accent-warning-light: #FEF3C7;
  --accent-danger: #EF4444;
  --accent-danger-light: #FEE2E2;
  --accent-info: #06B6D4;
  --accent-info-light: #CFFAFE;

  /* Neutral Colors */
  --text-primary: #1F2937;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --text-light: #F9FAFB;

  /* Background Colors */
  --bg-primary: #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-tertiary: #F3F4F6;
  --bg-dark: #111827;
  --bg-dark-secondary: #1F2937;

  /* Border Colors */
  --border-color: #E5E7EB;
  --border-light: #F3F4F6;
  --border-focus: #4F46E5;

  /* Shadows */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0, 0, 0, 0.06);
  --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);
  --shadow-inner: inset 0 2px 4px rgba(0, 0, 0, 0.06);

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

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;
  --transition-bounce: 300ms cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'Fira Code', 'JetBrains Mono', 'SF Mono', Consolas, monospace;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
}

/* ============================================
   Base Styles & Reset
   ============================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

main {
  flex: 1;
  background-color: var(--bg-secondary);
}

/* ============================================
   Typography
   ============================================ */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: var(--space-4);
}

h1 {
  font-size: 2.5rem;
  letter-spacing: -0.025em;
}

h2 {
  font-size: 2rem;
  letter-spacing: -0.02em;
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: var(--space-6);
}

h4 {
  font-size: 1.25rem;
  font-weight: 600;
}

h5 {
  font-size: 1.125rem;
  font-weight: 600;
}

h6 {
  font-size: 1rem;
  font-weight: 600;
}

p {
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.lead {
  font-size: 1.25rem;
  font-weight: 400;
  color: var(--text-secondary);
}

.text-muted {
  color: var(--text-muted) !important;
}

/* ============================================
   Navbar
   ============================================ */
.navbar {
  padding: var(--space-3) var(--space-6);
  transition: all var(--transition-base);
}

.navbar-dark {
  background: linear-gradient(135deg, var(--bg-dark) 0%, var(--bg-dark-secondary) 100%) !important;
  box-shadow: var(--shadow-lg);
}

.navbar-brand {
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  transition: opacity var(--transition-fast);
}

.navbar-brand:hover {
  opacity: 0.9;
}

.navbar-nav .nav-link {
  font-weight: 500;
  font-size: 0.9375rem;
  padding: var(--space-2) var(--space-4) !important;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  position: relative;
}

.navbar-nav .nav-link:hover {
  background-color: rgba(255, 255, 255, 0.1);
}

.navbar-nav .nav-link.active {
  background-color: var(--primary-color);
}

.navbar-toggler {
  border: none;
  padding: var(--space-2);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.navbar-toggler:focus {
  box-shadow: none;
  background-color: rgba(255, 255, 255, 0.1);
}

/* ============================================
   Hero Section
   ============================================ */
.hero-section {
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--bg-primary) 50%, var(--secondary-light) 100%);
  padding: var(--space-16) var(--space-4);
  border-radius: var(--radius-2xl);
  margin-bottom: var(--space-12);
  position: relative;
  overflow: hidden;
}



.hero-section h1 {
  position: relative;
  z-index: 1;
  font-size: 3rem;
  /* background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text; */
}

.hero-section .lead {
  position: relative;
  z-index: 1;
  max-width: 600px;
  margin: 0 auto var(--space-8);
}

.hero-section .bi-mortarboard-fill {
  font-size: 3.5rem;
  /* background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text; */
}

/* ============================================
   Feature Cards
   ============================================ */
.feature-card {
  background: var(--bg-primary);
  padding: var(--space-8);
  border-radius: var(--radius-xl);
  text-align: center;
  transition: all var(--transition-slow);
  border: 1px solid var(--border-color);
  height: 100%;
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  transform: scaleX(0);
  transition: transform var(--transition-slow);
}

.feature-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: transparent;
}

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

.feature-card i {
  font-size: 3rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-4);
  display: inline-block;
}

.feature-card h3 {
  font-size: 1.25rem;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.feature-card p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  margin-bottom: 0;
}

/* ============================================
   Cards - General
   ============================================ */
.card {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
  overflow: hidden;
}

.card:hover {
  transform: none;
}

.card-body {
  padding: var(--space-6);
}

.card-header {
  background: var(--bg-tertiary);
  border-bottom: 1px solid var(--border-color);
  padding: var(--space-4) var(--space-6);
  font-weight: 600;
}

.card-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--space-4) var(--space-6);
}

.card-title {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.card-text {
  color: var(--text-secondary);
}

/* Course Cards */
.course-card {
  position: relative;
  overflow: hidden;
}

.course-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-color);
}

.hover-lift {
  transition: all var(--transition-slow);
}

.hover-lift:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
  font-weight: 500;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  border: none;
  cursor: pointer;
}

.btn:focus {
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.3);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-hover) 100%);
  color: white;
  border: none;
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-hover) 0%, var(--primary-dark) 100%);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-outline-primary {
  background: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

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

.btn-success {
  background: linear-gradient(135deg, var(--accent-success) 0%, #059669 100%);
  color: white;
}

.btn-success:hover {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  transform: translateY(-2px);
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: 1.0625rem;
  border-radius: var(--radius-lg);
}

.btn-sm {
  padding: var(--space-2) var(--space-4);
  font-size: 0.875rem;
}

.btn-link {
  background: none;
  border: none;
  color: var(--primary-color);
  padding: 0;
  text-decoration: none;
}

.btn-link:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

/* ============================================
   Badges
   ============================================ */
.badge {
  font-weight: 500;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  letter-spacing: 0.02em;
}

.bg-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-hover)) !important;
}

.bg-success {
  background: linear-gradient(135deg, var(--accent-success), #059669) !important;
}

.bg-info {
  background: linear-gradient(135deg, var(--accent-info), #0891B2) !important;
}

.bg-warning {
  background: linear-gradient(135deg, var(--accent-warning), #D97706) !important;
  color: white !important;
}

.bg-danger {
  background: linear-gradient(135deg, var(--accent-danger), #DC2626) !important;
}

.bg-secondary {
  background: var(--text-secondary) !important;
}

.bg-light {
  background: var(--bg-tertiary) !important;
  border: 1px solid var(--border-color);
}

/* ============================================
   Forms
   ============================================ */
.form-control {
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-3) var(--space-4);
  font-size: 1rem;
  transition: all var(--transition-fast);
  background-color: var(--bg-primary);
}

.form-control:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
  outline: none;
}

.form-control::placeholder {
  color: var(--text-muted);
}

.form-label {
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

/* ============================================
   Alerts
   ============================================ */
.alert {
  border: none;
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-6);
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
}

.alert-success {
  background-color: var(--accent-success-light);
  color: #065F46;
  border-left: 4px solid var(--accent-success);
}

.alert-danger {
  background-color: var(--accent-danger-light);
  color: #991B1B;
  border-left: 4px solid var(--accent-danger);
}

.alert-warning {
  background-color: var(--accent-warning-light);
  color: #92400E;
  border-left: 4px solid var(--accent-warning);
}

.alert-info {
  background-color: var(--accent-info-light);
  color: #0E7490;
  border-left: 4px solid var(--accent-info);
}

/* ============================================
   List Groups
   ============================================ */
.list-group {
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.list-group-item {
  border: none;
  border-bottom: 1px solid var(--border-color);
  padding: var(--space-4) var(--space-5);
  background: var(--bg-primary);
  transition: all var(--transition-fast);
}

.list-group-item:last-child {
  border-bottom: none;
}

.list-group-item:hover {
  background-color: var(--bg-secondary);
}

.list-group-item strong {
  color: var(--primary-color);
  margin-right: var(--space-2);
}

.list-group-item.active {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
  border-color: transparent;
}

.list-group-item-action:hover {
  background-color: var(--primary-light);
  color: var(--primary-color);
}

.list-group-item-sprint {
  margin: 0;
  padding: 0;
}

/* Sprint Links */
a.sprint-link {
  color: var(--text-primary);
  text-decoration: none;
  display: block;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  font-weight: 400;
}

a.sprint-link:hover {
  background-color: var(--primary-light);
  color: var(--primary-color);
  text-decoration: none;
  transform: translateX(4px);
}

span.sprint-link {
  color: var(--text-muted);
  text-decoration: none;
  display: block;
  padding: var(--space-3) var(--space-4);
  font-weight: 500;
}

/* ============================================
   Stats Section
   ============================================ */
.display-4 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.text-primary {
  color: var(--primary-color) !important;
}

.text-success {
  color: var(--accent-success) !important;
}

.text-info {
  color: var(--accent-info) !important;
}

.text-warning {
  color: var(--accent-warning) !important;
}

/* ============================================
   Sprint Page Styles
   ============================================ */
.sprint-number {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.875rem;
}

.about-sprint-info span {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  background: var(--bg-tertiary);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.about-sprint-info span i {
  color: var(--accent-success);
}

.tags span {
  background: var(--primary-light);
  color: var(--primary-color);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  font-weight: 500;
}

.nav-prev-next a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9375rem;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--primary-light);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-prev-next a:hover {
  background: var(--primary-color);
  color: white;
}

/* Video Container */
.ratio-16x9 {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

/* ============================================
   Code Blocks
   ============================================ */
pre {
  background: var(--bg-dark);
  color: #E5E7EB;
  padding: var(--space-5);
  border-radius: var(--radius-lg);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.7;
  box-shadow: var(--shadow-inner);
  border: 1px solid var(--border-color);
}

code {
  font-family: var(--font-mono);
  background: var(--bg-tertiary);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  font-size: 0.875em;
  color: var(--primary-color);
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

/* ============================================
   Help Link
   ============================================ */
a.help-link.btn-link {
  color: var(--text-muted);
  text-decoration: none;
  position: relative;
  top: -1px;
  transition: color var(--transition-fast);
}

a.help-link.btn-link:hover {
  color: var(--primary-color);
}

a.help-link.btn-link:hover i {
  color: var(--primary-color);
}

a.help-link.btn-link>i {
  color: var(--text-muted);
  text-decoration: none;
}

/* ============================================
   Cabinet / Profile Page
   ============================================ */
.bi-person-circle {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

#my-profile-page .list-group-item {
  border: none;
  border-radius: var(--radius-md);
  margin-bottom: var(--space-1);
  transition: all var(--transition-fast);
  font-weight: 500;
}

#my-profile-page .list-group-item:hover {
  background: var(--primary-light);
  color: var(--primary-color);
}

#my-profile-page .list-group-item.active {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
  color: white;
}

#my-profile-page .list-group-item.text-danger:hover {
  background: var(--accent-danger-light);
  color: var(--accent-danger);
}

/* ============================================
   Footer
   ============================================ */
footer {
  background: var(--bg-primary);
  border-top: 1px solid var(--border-color);
  margin-top: auto;
}

footer h5 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-4);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

footer .nav-link {
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  font-size: 0.9375rem;
}

footer .nav-link:hover {
  color: var(--primary-color);
  transform: translateX(4px);
}

footer .text-body-secondary {
  color: var(--text-secondary) !important;
}

footer .link-body-emphasis {
  color: var(--text-primary) !important;
}

/* ============================================
   CTA (Call to Action) Section
   ============================================ */
.border-primary {
  border: 2px solid var(--primary-color) !important;
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--bg-primary) 100%);
}

.border-primary .card-body {
  position: relative;
}

.border-primary h2 {
  color: var(--primary-color);
}

/* ============================================
   Breadcrumbs
   ============================================ */
.breadcrumb {
  background: var(--bg-tertiary);
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-lg);
}

.breadcrumb-item a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.breadcrumb-item a:hover {
  color: var(--primary-hover);
}

.breadcrumb-item.active {
  color: var(--text-secondary);
}

/* ============================================
   Login Card Styles
   ============================================ */
.col-lg-4>.card {
  border: none;
  box-shadow: var(--shadow-xl);
}

.col-lg-4>.card .card-body {
  padding: var(--space-10);
}

.col-lg-4>.card .card-title,
.card .card-title {
  font-size: 1.75rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
} {
  font-size: 1.75rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================
   Progress Bar
   ============================================ */
.progress {
  height: 8px;
  border-radius: var(--radius-full);
  background-color: var(--bg-tertiary);
  overflow: hidden;
}

.progress-bar {
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

/* ============================================
   Sticky Sidebar
   ============================================ */
.sticky-top {
  top: var(--space-6);
}

/* ============================================
   Utility Classes
   ============================================ */
.gap-3 {
  gap: var(--space-4) !important;
}

.g-4 {
  --bs-gutter-y: var(--space-6);
  --bs-gutter-x: var(--space-6);
}

.py-5 {
  padding-top: var(--space-12) !important;
  padding-bottom: var(--space-12) !important;
}

.mb-5 {
  margin-bottom: var(--space-12) !important;
}

.mb-4 {
  margin-bottom: var(--space-8) !important;
}

/* ============================================
   Scrollbar Styling
   ============================================ */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: var(--radius-full);
  transition: background var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ============================================
   Selection Styling
   ============================================ */
::selection {
  background-color: var(--primary-color);
  color: white;
}

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

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {

  0%,
  100% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.05);
  }
}

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

.animate-slide-up {
  animation: slideUp 0.5s ease-out forwards;
}

/* ============================================
   Responsive Design - Tablet
   ============================================ */
@media (max-width: 991.98px) {
  .hero-section {
    padding: var(--space-10) var(--space-4);
  }

  .hero-section h1 {
    font-size: 2.25rem;
  }

  .hero-section .lead {
    font-size: 1.125rem;
  }

  .feature-card {
    padding: var(--space-6);
  }

  .feature-card i {
    font-size: 2.5rem;
  }

  .display-4 {
    font-size: 2rem;
  }

  .navbar-collapse {
    background: var(--bg-dark-secondary);
    padding: var(--space-4);
    margin-top: var(--space-4);
    border-radius: var(--radius-lg);
  }

  .navbar-nav .nav-link {
    padding: var(--space-3) var(--space-4) !important;
  }
}

/* ============================================
   Responsive Design - Mobile
   ============================================ */
@media (max-width: 767.98px) {
  :root {
    --space-16: 3rem;
    --space-12: 2rem;
    --space-10: 1.5rem;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  h3 {
    font-size: 1.25rem;
  }

  .hero-section {
    padding: var(--space-8) var(--space-4);
    border-radius: var(--radius-xl);
  }

  .hero-section h1 {
    font-size: 1.75rem;
  }

  .hero-section .bi-mortarboard-fill {
    font-size: 2.5rem;
  }

  .hero-section .lead {
    font-size: 1rem;
  }

  .feature-card {
    padding: var(--space-5);
  }

  .feature-card i {
    font-size: 2rem;
  }

  .feature-card h3 {
    font-size: 1.125rem;
  }

  .card-body {
    padding: var(--space-4);
  }

  .display-4 {
    font-size: 1.75rem;
  }

  .btn-lg {
    padding: var(--space-3) var(--space-5);
    font-size: 1rem;
  }

  .d-flex.justify-content-center.gap-3 {
    flex-direction: column;
    align-items: stretch;
  }

  .d-flex.justify-content-center.gap-3 .btn {
    width: 100%;
  }

  footer .col-md-4,
  footer .col-3,
  footer .col-md-2,
  footer .col-md-3 {
    margin-bottom: var(--space-6);
  }

  .sprint-number,
  .about-sprint-info,
  .tags,
  .nav-prev-next {
    margin-bottom: var(--space-3);
  }

  .mb-4.d-flex.justify-content-between {
    flex-direction: column;
    gap: var(--space-3);
  }

  /* Mobile Navbar Improvements */
  .navbar-brand {
    font-size: 1.2rem;
  }

  /* Stack sprint navigation on mobile */
  .nav-prev-next {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
  }

  .nav-prev-next a {
    flex: 1;
    min-width: 120px;
    justify-content: center;
    font-size: 0.875rem;
  }

  /* Mobile table scroll */
  .table-responsive {
    margin: 0 calc(var(--space-4) * -1);
    padding: 0 var(--space-4);
  }

  /* Adjust course detail page layout */
  .col-md-8,
  .col-md-4 {
    padding-left: var(--space-3);
    padding-right: var(--space-3);
  }

  /* Cabinet sidebar on mobile */
  .col-lg-3 {
    margin-bottom: var(--space-6);
  }

  .col-lg-3 .card.sticky-top {
    position: relative !important;
    top: 0 !important;
  }
}

/* ============================================
   Responsive Design - Small Mobile
   ============================================ */
@media (max-width: 575.98px) {
  h1 {
    font-size: 1.5rem;
  }

  .hero-section h1 {
    font-size: 1.5rem;
  }

  .display-4 {
    font-size: 1.5rem;
  }

  .feature-card {
    padding: var(--space-4);
  }

  .card-body {
    padding: var(--space-4);
  }

  footer {
    text-align: center;
  }

  footer .nav.flex-column {
    align-items: center;
  }

  footer .nav-link:hover {
    transform: none;
  }

  /* Full width buttons on very small screens */
  .btn {
    width: 100%;
    justify-content: center;
  }

  .badge {
    font-size: 0.6875rem;
    padding: 0.15rem 0.5rem;
  }
}

/* ============================================
   Print Styles
   ============================================ */
@media print {

  .navbar,
  footer,
  .no-print {
    display: none !important;
  }

  body {
    background: white;
  }

  .card {
    box-shadow: none;
    border: 1px solid #ddd;
  }

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

/* ============================================
   Accessibility - Focus Styles
   ============================================ */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Skip to main content link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-color);
  color: white;
  padding: var(--space-2) var(--space-4);
  z-index: 100;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
}

/* ============================================
   Reduced Motion Preference
   ============================================ */
@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }
}

.price-block {
  font-family: inherit;
}

.price-sale {
  display: flex;
  align-items: center;
  justify-content: end;
  gap: 10px;
}

.price-old {
  text-decoration: line-through;
  color: #888;
  font-size: 0.95rem;
}

.price-new {
  font-size: 1.6rem;
  font-weight: 700;
  color: #0dcf75;
  /* зеленый */
}

.price-badge {
  background: #dc3545;
  color: #fff;
  font-size: 0.75rem;
  padding: 3px 8px;
  border-radius: 6px;
  font-weight: 600;
}

.price-regular .price-new {
  color: #212529;
}

.faq {
  max-width: 800px;
  margin: 60px auto;
  padding: 0 20px;
  font-family: system-ui, sans-serif;
}

.faq-title {
  text-align: center;
  margin-bottom: 30px;
}

.faq-item {
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  margin-bottom: 10px;
  background: #fff;
}

.faq-item summary {
  cursor: pointer;
  padding: 16px 20px;
  font-weight: 600;
  list-style: none;
  position: relative;
}

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 12px;
  font-size: 20px;
  transition: transform 0.2s;
}

.faq-item[open] summary::after {
  content: "−";
}

details.faq-item {scroll-margin-top: 30px;}

.faq-content {
  padding: 0 20px 18px 20px;
  color: #555;
  line-height: 1.6;
}

.faq-content ul {
  margin-top: 10px;
  padding-left: 18px;
}

.code-checkout-result {
  list-style-type: none;
  margin-left: 0;
  padding-left:0;
}

.widget-contacts {
  list-style-type: none;
  line-height: 175%;
  margin-left: 0;
  padding-left:0;
}

.widget-contacts li a {
  text-decoration: none;
  transition: all ease .5s;
}

.widget-contacts li a:hover {
  text-decoration: underline;
}

.logo {
  text-decoration: none;;
}

.footer-menu li a {
  text-decoration: none;
}

.footer-menu li a:hover {
  text-decoration: underline;
}

.ask-us {
  position: fixed;
  bottom: 200px;  /* отступ от низа */
  right: -70px;   /* отступ от правого края */
  opacity: 0;    /* начально скрыт */
  transform: translateY(20px); /* немного смещён вниз */
  transition: opacity 0.5s ease, transform 0.5s ease;
  z-index: 9999; /* поверх всего */
  pointer-events: none; /* чтобы не мешал до появления */
}

/* Класс для появления после 5 секунд */
.ask-us.show {
  opacity: 1;
  transform: translateY(0) rotate(270deg);;
  pointer-events: auto;
}