/* ============================================
   Mini Hippo - Modern UI/UX Stylesheet
   Clean, Modern Design with Subtle Animations
   ============================================ */

:root {
  /* Color Palette - Minimal & Modern */
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --secondary-color: #64748b;
  --accent-color: #0ea5e9;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --warning-color: #f59e0b;
  --info-color: #06b6d4;
  
  /* Neutral Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --border-color: #e2e8f0;
  
  /* 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);
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
}

/* ============================================
   Global Improvements
   ============================================ */

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   Sidebar Enhancements
   ============================================ */

.sidebar {
  background: linear-gradient(180deg, #1e293b 0%, #0f172a 100%);
  box-shadow: var(--shadow-xl);
  transition: transform var(--transition-base);
}

.sidebar-brand {
  padding: 1.5rem 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.brand-link {
  transition: opacity var(--transition-fast);
}

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

.brand-image {
  transition: transform var(--transition-base);
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

.brand-link:hover .brand-image {
  transform: scale(1.05);
}

.brand-text {
  font-weight: 600;
  letter-spacing: -0.02em;
}

/* Sidebar Navigation */
.nav-link {
  border-radius: var(--radius-md);
  margin: 0.25rem 0.5rem;
  padding: 0.75rem 1rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 3px;
  background: var(--primary-color);
  transform: scaleY(0);
  transition: transform var(--transition-base);
}

.nav-link:hover::before,
.nav-link.active::before {
  transform: scaleY(1);
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.08);
  transform: translateX(4px);
}

.nav-link.active {
  background: rgba(37, 99, 235, 0.15);
  color: #60a5fa;
}

.nav-icon {
  transition: transform var(--transition-fast);
}

.nav-link:hover .nav-icon {
  transform: scale(1.1);
}

/* ============================================
   Button Modernization
   ============================================ */

.btn {
  border-radius: var(--radius-lg);
  font-weight: 500;
  padding: 0.875rem 1.5rem;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
  border: none;
  box-shadow: var(--shadow-sm);
  letter-spacing: 0.01em;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn:active {
  transform: translateY(0);
  box-shadow: var(--shadow-md);
}

/* Button Color Variants */
.btn-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-hover) 100%);
  color: white;
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-hover) 0%, var(--primary-color) 100%);
}

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

.btn-danger {
  background: linear-gradient(135deg, var(--danger-color) 0%, #dc2626 100%);
  color: white;
}

.btn-info {
  background: linear-gradient(135deg, var(--info-color) 0%, #0891b2 100%);
  color: white;
}

.btn-secondary {
  background: linear-gradient(135deg, var(--secondary-color) 0%, #475569 100%);
  color: white;
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.1rem;
  border-radius: var(--radius-xl);
}

/* ============================================
   Card & Container Improvements
   ============================================ */

.container-fluid {
  animation: fadeInUp 0.6s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Content Sections */
.col-md-3 {
  animation: fadeInUp 0.6s ease-out;
  animation-fill-mode: both;
}

.col-md-3:nth-child(1) { animation-delay: 0.1s; }
.col-md-3:nth-child(2) { animation-delay: 0.2s; }
.col-md-3:nth-child(3) { animation-delay: 0.3s; }
.col-md-3:nth-child(4) { animation-delay: 0.4s; }
.col-md-3:nth-child(5) { animation-delay: 0.5s; }

h4.text-center {
  color: var(--text-primary);
  font-weight: 600;
  margin-bottom: 1.5rem;
  position: relative;
  padding-bottom: 0.75rem;
}

h4.text-center::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 50px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  border-radius: 2px;
}

/* ============================================
   Header Improvements
   ============================================ */

.app-header {
  background: var(--bg-primary);
  box-shadow: var(--shadow-sm);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
}

.navbar-nav .nav-link {
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.navbar-nav .nav-link:hover {
  background: var(--bg-tertiary);
}

/* ============================================
   Content Area
   ============================================ */

.app-content-header {
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  border-bottom: 1px solid var(--border-color);
  padding: 2rem 0;
}

h3.mb-0 {
  color: var(--text-primary);
  font-weight: 700;
  letter-spacing: -0.03em;
  animation: fadeInLeft 0.6s ease-out;
}

@keyframes fadeInLeft {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ============================================
   Smooth Scroll
   ============================================ */

html {
  scroll-behavior: smooth;
}

/* ============================================
   Loading States
   ============================================ */

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.loading {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* ============================================
   Icon Animations
   ============================================ */

.bi {
  transition: all var(--transition-fast);
}

.btn:hover .bi {
  transform: scale(1.15);
}

/* ============================================
   Responsive Improvements
   ============================================ */

@media (max-width: 768px) {
  .btn-lg {
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
  }
  
  .col-md-3 {
    margin-bottom: 1.5rem;
  }
}

/* ============================================
   Focus States (Accessibility)
   ============================================ */

.btn:focus-visible,
.nav-link:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* ============================================
   Utility Classes
   ============================================ */

.shadow-modern {
  box-shadow: var(--shadow-lg);
}

.rounded-modern {
  border-radius: var(--radius-xl);
}

.gradient-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
}

/* ============================================
   Hover Effects
   ============================================ */

.hover-lift {
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.hover-lift:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

/* ============================================
   Sidebar Toggle Animation
   ============================================ */

.sidebar {
  transition: transform var(--transition-slow) cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   Button Icon Spacing
   ============================================ */

.btn .bi {
  margin-right: 0.5rem;
  transition: transform var(--transition-fast);
}

.btn:hover .bi {
  transform: translateX(2px);
}

/* ============================================
   Modern Scrollbar (Webkit)
   ============================================ */

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--secondary-color);
  border-radius: 5px;
}

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