/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary-color: #4F46E5;
  --primary-dark: #4338CA;
  --secondary-color: #10B981;
  --danger-color: #EF4444;
  --text-dark: #1F2937;
  --text-light: #6B7280;
  --bg-light: #F9FAFB;
  --border-color: #E5E7EB;
  --white: #FFFFFF;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: var(--bg-light);
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Navigation */
.navbar {
  background-color: var(--white);
  box-shadow: var(--shadow-sm);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
}

.navbar-menu {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.navbar-menu a {
  color: var(--text-dark);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.navbar-menu a:hover {
  color: var(--primary-color);
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
}

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

.btn-primary:hover {
  background-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

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

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

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

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

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-dark);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: border-color 0.3s;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

/* Cards */
.card {
  background-color: var(--white);
  border-radius: 0.75rem;
  padding: 2rem;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.3s;
}

.card:hover {
  box-shadow: var(--shadow-md);
}

/* Grid Layout */
.grid {
  display: grid;
  gap: 2rem;
  margin-top: 2rem;
}

.grid-cols-1 {
  grid-template-columns: repeat(1, 1fr);
}

.grid-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

/* Item Card */
.item-card {
  background-color: var(--white);
  border-radius: 0.75rem;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s, box-shadow 0.3s;
}

.item-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.item-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  background-color: var(--bg-light);
}

.item-content {
  padding: 1.5rem;
}

.item-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-dark);
}

.item-description {
  color: var(--text-light);
  margin-bottom: 1rem;
  line-height: 1.5;
}

.item-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  color: var(--text-light);
  margin-bottom: 1rem;
}

.item-actions {
  display: flex;
  gap: 0.5rem;
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  margin-top: 2rem;
}

.pagination button {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-color);
  background-color: var(--white);
  border-radius: 0.5rem;
  cursor: pointer;
  transition: all 0.3s;
}

.pagination button:hover:not(:disabled) {
  background-color: var(--primary-color);
  color: var(--white);
  border-color: var(--primary-color);
}

.pagination button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.pagination .page-info {
  padding: 0.5rem 1rem;
  font-weight: 600;
}

/* Search Bar */
.search-container {
  margin: 2rem 0;
}

.search-input {
  width: 100%;
  max-width: 500px;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  font-size: 1rem;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 4rem 0;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: var(--white);
  margin-bottom: 3rem;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.9;
}

/* Auth Pages */
.auth-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}

.auth-card {
  width: 100%;
  max-width: 400px;
}

.auth-title {
  text-align: center;
  font-size: 2rem;
  margin-bottom: 2rem;
  color: var(--text-dark);
}

/* Alert Messages */
.alert {
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 1rem;
  font-weight: 500;
}

.alert-success {
  background-color: #D1FAE5;
  color: #065F46;
  border: 1px solid #6EE7B7;
}

.alert-error {
  background-color: #FEE2E2;
  color: #991B1B;
  border: 1px solid #FCA5A5;
}

.alert-info {
  background-color: #DBEAFE;
  color: #1E40AF;
  border: 1px solid #93C5FD;
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

.modal.active {
  display: flex;
}

.modal-content {
  background-color: var(--white);
  padding: 2rem;
  border-radius: 0.75rem;
  max-width: 500px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.modal-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-light);
}

/* Loading Spinner */
.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: var(--white);
  animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 2rem;
  }

  .hero p {
    font-size: 1rem;
  }

  .grid-cols-3,
  .grid-cols-2 {
    grid-template-columns: repeat(1, 1fr);
  }

  .navbar-menu {
    gap: 1rem;
  }

  .item-actions {
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }

  .btn {
    width: 100%;
    text-align: center;
  }

  .pagination {
    flex-wrap: wrap;
  }
}

/* Utility Classes */
.text-center {
  text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.hidden {
  display: none;
}