/* Global Styles */
:root {
  --primary-color: #4361ee;
  --secondary-color: #3f37c9;
  --accent-color: #4cc9f0;
  --success-color: #4caf50;
  --warning-color: #ff9800;
  --error-color: #f44336;
  --light-color: #f8f9fa;
  --dark-color: #212529;
  --gray-color: #6c757d;
  --border-radius: 8px;
  --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --transition: all 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  color: var(--dark-color);
  line-height: 1.6;
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
}

/* Login Page */
.login-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 20px;
}

.login-card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  padding: 2rem;
  width: 100%;
  max-width: 400px;
  animation: fadeIn 0.5s ease;
  background: linear-gradient(135deg, #ffffff 0%, #f8f9ff 100%);
}

.login-card h1 {
  text-align: center;
  margin-bottom: 1.5rem;
  color: var(--primary-color);
  font-size: 2rem;
}

/* Dashboard Styles */
#app {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  overflow: hidden;
  animation: slideIn 0.5s ease;
}

.header {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  color: white;
  padding: 1.5rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.header h2 {
  font-size: 1.8rem;
  font-weight: 600;
}

/* Tabs */
.tabs {
  display: flex;
  background: #f1f3f9;
  border-bottom: 1px solid #e0e0e0;
  overflow-x: auto;
}

.tab {
  padding: 1rem 1.5rem;
  background: transparent;
  border: none;
  cursor: pointer;
  font-weight: 500;
  color: var(--gray-color);
  transition: var(--transition);
  border-bottom: 3px solid transparent;
  white-space: nowrap;
}

.tab:hover {
  background: #e2e6f1;
  color: var(--primary-color);
}

.tab.active {
  color: var(--primary-color);
  border-bottom: 3px solid var(--primary-color);
  background: white;
}

/* Cards */
.card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  transition: var(--transition);
  border: 1px solid #eef2f7;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.card h2 {
  color: var(--primary-color);
  margin-bottom: 1rem;
  font-size: 1.5rem;
  border-bottom: 2px solid #f0f2f5;
  padding-bottom: 0.5rem;
}

/* Book Cards */
.book-card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  padding: 1.5rem;
  transition: var(--transition);
  border: 1px solid #eef2f7;
  position: relative;
  overflow: hidden;
}

.book-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
}

.book-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
}

.book-card h4 {
  color: var(--dark-color);
  margin-bottom: 0.75rem;
  font-size: 1.2rem;
}

.book-card p {
  margin-bottom: 0.5rem;
  color: var(--gray-color);
}

/* Stats Cards */
.stats-card {
  text-align: center;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  color: white;
  box-shadow: var(--box-shadow);
  transition: var(--transition);
}

.stats-card:hover {
  transform: scale(1.05);
}

.stats-card.blue {
  background: linear-gradient(135deg, var(--primary-color) 0%, #3a0ca3 100%);
}

.stats-card.green {
  background: linear-gradient(135deg, var(--success-color) 0%, #2e7d32 100%);
}

.stats-card.orange {
  background: linear-gradient(135deg, var(--warning-color) 0%, #ef6c00 100%);
}

.stats-card.purple {
  background: linear-gradient(135deg, #7b2cbf 0%, #5a189a 100%);
}

.stats-card h3 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

/* Forms */
.form-group {
  margin-bottom: 1.5rem;
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--dark-color);
}

.input, .select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid #ddd;
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: var(--transition);
}

.input:focus, .select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  transition: var(--transition);
  text-align: center;
  display: inline-block;
}

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

.btn-primary:hover {
  background: linear-gradient(135deg, #3a0ca3 0%, #372a8c 100%);
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.btn-secondary {
  background: #6c757d;
  color: white;
}

.btn-secondary:hover {
  background: #5a6268;
  transform: translateY(-2px);
}

.btn-success {
  background: var(--success-color);
  color: white;
}

.btn-success:hover {
  background: #43a047;
  transform: translateY(-2px);
}

.btn-danger {
  background: var(--error-color);
  color: white;
}

.btn-danger:hover {
  background: #e53935;
  transform: translateY(-2px);
}

.btn-warning {
  background: var(--warning-color);
  color: white;
}

.btn-warning:hover {
  background: #f57c00;
  transform: translateY(-2px);
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* Badges */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 500;
}

.badge-blue {
  background: rgba(67, 97, 238, 0.1);
  color: var(--primary-color);
}

.badge-green {
  background: rgba(76, 175, 80, 0.1);
  color: var(--success-color);
}

.badge-orange {
  background: rgba(255, 152, 0, 0.1);
  color: var(--warning-color);
}

.badge-red {
  background: rgba(244, 67, 54, 0.1);
  color: var(--error-color);
}

.badge-purple {
  background: rgba(123, 44, 191, 0.1);
  color: #7b2cbf;
}

.badge-yellow {
  background: rgba(255, 235, 59, 0.1);
  color: #fbc02d;
}

/* Alerts */
.alert {
  padding: 1rem;
  border-radius: var(--border-radius);
  margin-bottom: 1rem;
}

.alert-success {
  background: rgba(76, 175, 80, 0.1);
  color: var(--success-color);
  border: 1px solid rgba(76, 175, 80, 0.2);
}

.alert-error {
  background: rgba(244, 67, 54, 0.1);
  color: var(--error-color);
  border: 1px solid rgba(244, 67, 54, 0.2);
}

.alert-info {
  background: rgba(76, 201, 240, 0.1);
  color: var(--accent-color);
  border: 1px solid rgba(76, 201, 240, 0.2);
}

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
}

.table th,
.table td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid #eee;
}

.table th {
  background: #f8f9fa;
  font-weight: 600;
  color: var(--dark-color);
}

.table tr:hover {
  background: #f8f9ff;
}

/* Grid System */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

/* Search Box */
.search-box {
  margin-bottom: 1.5rem;
}

.search-box .input {
  padding: 1rem;
  font-size: 1rem;
}

/* Utilities */
.hidden {
  display: none !important;
}

.empty-state {
  text-align: center;
  padding: 3rem;
  color: var(--gray-color);
}

.empty-state::before {
  content: '📚';
  font-size: 3rem;
  display: block;
  margin-bottom: 1rem;
}

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

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

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

/* Responsive Design */
@media (max-width: 768px) {
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .tabs {
    flex-direction: column;
  }
  
  .header {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
  
  .login-card {
    padding: 1.5rem;
  }
}

/* Password Toggle */
.password-toggle {
  cursor: pointer;
  color: var(--primary-color);
  margin-left: 0.5rem;
  font-size: 0.875rem;
}

/* Actions */
.actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* Success Message */
.success-message {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--success-color);
  color: white;
  padding: 1rem 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  z-index: 1000;
  animation: fadeIn 0.3s ease;
}