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

:root {
  --primary-color: #3b82f6;
  --primary-dark: #2563eb;
  --secondary-color: #6b7280;
  --success-color: #10b981;
  --error-color: #ef4444;
  --background: #f9fafb;
  --surface: #ffffff;
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --border-color: #e5e7eb;
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background-color: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* Navbar */
.navbar {
  background-color: var(--surface);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color 0.2s;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1rem;
}

.nav-link:hover {
  color: var(--primary-color);
}

.nav-link.active {
  color: var(--primary-color);
  font-weight: 600;
}

.btn-logout {
  color: var(--error-color);
}

/* Container */
.container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 2rem;
}

/* Page Header */
.page-header {
  text-align: center;
  margin-bottom: 3rem;
}

.page-header h2 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.page-header p {
  color: var(--text-secondary);
  font-size: 1.125rem;
}

/* User Info */
.user-info {
  background-color: var(--surface);
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
  text-align: center;
}

.user-info-banner {
  background-color: #dbeafe;
  padding: 0.75rem;
  border-radius: 0.375rem;
  margin-bottom: 1.5rem;
  text-align: center;
  color: var(--primary-dark);
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-block;
  text-align: center;
}

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

.btn-primary:hover {
  background-color: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}

.btn-primary:disabled {
  background-color: var(--secondary-color);
  cursor: not-allowed;
  transform: none;
}

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

.btn-secondary:hover {
  background-color: #4b5563;
}

.btn-danger {
  background-color: var(--error-color);
  color: white;
  font-size: 0.875rem;
  padding: 0.5rem 1rem;
}

.btn-danger:hover {
  background-color: #dc2626;
}

.btn-block {
  width: 100%;
}

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

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
}

.form-group input[type="text"],
.form-group input[type="password"] {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: border-color 0.2s;
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* File Input */
.file-input-wrapper {
  position: relative;
}

.file-input-wrapper input[type="file"] {
  position: absolute;
  opacity: 0;
  width: 100%;
  height: 100%;
  cursor: pointer;
}

.file-input-label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem;
  border: 2px dashed var(--border-color);
  border-radius: 0.5rem;
  background-color: var(--background);
  cursor: pointer;
  transition: all 0.2s;
}

.file-input-label:hover {
  border-color: var(--primary-color);
  background-color: #eff6ff;
}

.file-icon {
  font-size: 1.5rem;
}

/* Messages */
.error-message {
  background-color: #fee2e2;
  color: #991b1b;
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 1rem;
}

.success-message {
  background-color: #d1fae5;
  color: #065f46;
  padding: 1rem;
  border-radius: 0.5rem;
  margin-bottom: 1rem;
}

/* Loading Spinner */
.loading-spinner {
  text-align: center;
  padding: 3rem;
}

.spinner {
  border: 4px solid var(--border-color);
  border-top: 4px solid var(--primary-color);
  border-radius: 50%;
  width: 50px;
  height: 50px;
  animation: spin 1s linear infinite;
  margin: 0 auto 1rem;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 4rem 2rem;
}

.empty-icon {
  font-size: 4rem;
  margin-bottom: 1rem;
}

.empty-state h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.empty-state p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

/* Login Container */
.login-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: calc(100vh - 200px);
}

.login-card {
  background-color: var(--surface);
  padding: 2.5rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 450px;
}

.login-header {
  text-align: center;
  margin-bottom: 2rem;
}

.login-header h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.login-header p {
  color: var(--text-secondary);
}

.demo-credentials {
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.demo-credentials h4 {
  margin-bottom: 1rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.credentials-grid {
  display: grid;
  gap: 0.75rem;
}

.credential-item {
  background-color: var(--background);
  padding: 0.75rem;
  border-radius: 0.375rem;
  font-size: 0.875rem;
}

.credential-item code {
  background-color: var(--surface);
  padding: 0.25rem 0.5rem;
  border-radius: 0.25rem;
  font-family: monospace;
  margin-left: 0.5rem;
}

/* Upload Container */
.upload-container {
  max-width: 700px;
  margin: 0 auto;
}

.upload-card {
  background-color: var(--surface);
  padding: 2.5rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-lg);
}

.upload-header {
  text-align: center;
  margin-bottom: 2rem;
}

.upload-header h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.upload-header p {
  color: var(--text-secondary);
}

.auth-required {
  text-align: center;
  padding: 3rem 2rem;
}

.auth-icon {
  font-size: 4rem;
  margin-bottom: 1rem;
}

.auth-required h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.auth-required p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}

/* Image Preview */
.image-preview {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.preview-item {
  position: relative;
  aspect-ratio: 1;
  border-radius: 0.5rem;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.preview-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.preview-remove {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  background-color: var(--error-color);
  color: white;
  border: none;
  border-radius: 50%;
  width: 28px;
  height: 28px;
  font-size: 1.25rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0.9;
  transition: opacity 0.2s;
}

.preview-remove:hover {
  opacity: 1;
}

/* Progress Bar */
.upload-progress {
  margin-bottom: 1.5rem;
}

.progress-bar {
  width: 100%;
  height: 8px;
  background-color: var(--border-color);
  border-radius: 1rem;
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.progress-fill {
  height: 100%;
  background-color: var(--primary-color);
  transition: width 0.3s ease;
}

.progress-text {
  display: block;
  text-align: center;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* Form Actions */
.form-actions {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.form-actions .btn {
  flex: 1;
}

/* Gallery Container */
.gallery-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.gallery-card {
  background-color: var(--surface);
  border-radius: 1rem;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s;
}

.gallery-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.gallery-images {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.25rem;
  background-color: var(--background);
}

.gallery-image {
  aspect-ratio: 1;
  overflow: hidden;
  cursor: pointer;
}

.gallery-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s;
}

.gallery-image img:hover {
  transform: scale(1.1);
}

.gallery-info {
  padding: 1.25rem;
}

.gallery-info h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.gallery-meta {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 0.75rem;
}

.gallery-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-color);
}

.image-count {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.9);
}

.modal.active {
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content {
  max-width: 90%;
  max-height: 90%;
}

.modal-content img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.modal-close {
  position: absolute;
  top: 2rem;
  right: 2rem;
  color: white;
  font-size: 3rem;
  font-weight: bold;
  cursor: pointer;
  background: none;
  border: none;
  padding: 0;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s;
}

.modal-close:hover {
  transform: scale(1.1);
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  margin-top: 3rem;
  padding: 2rem 0;
}

.pagination .btn {
  min-width: 120px;
}

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

.page-info {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }

  .gallery-container {
    grid-template-columns: 1fr;
  }

  .login-card,
  .upload-card {
    padding: 1.5rem;
  }

  .credentials-grid {
    grid-template-columns: 1fr;
  }
}