:root {
        --primary-color: rgb(34, 93, 203);
        --primary-dark: #1505a1;
        --secondary-color: #4ECDC4;
        --dark-color: #2D3436;
        --light-color: #F5F6FA;
        --gray-color: #636E72;
        --light-gray: #DFE6E9;
        --shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
        --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
      }
      
      * {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
      }
      
      body {
        font-family: 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', sans-serif;
        background-color: #f9f9f9;
        color: var(--dark-color);
        line-height: 1.6;
      }
      
      .photo-gallery-app {
        max-width: 1800px;
        margin: 0 auto;
        padding: 0 20px;
      }
      
      .app-header {
        text-align: center;
        padding: 40px 0 30px;
        background: linear-gradient(135deg, #ffffff 0%, #f9f9f9 100%);
        border-bottom: 1px solid var(--light-gray);
        margin-bottom: 30px;
      }
      
      .app-header h1 {
        font-size: 2.5rem;
        font-weight: 700;
        color: var(--dark-color);
        margin-bottom: 10px;
      }
      
      .subtitle {
        font-size: 1.1rem;
        color: var(--gray-color);
        margin-bottom: 30px;
      }
      
      .search-container {
        max-width: 800px;
        margin: 0 auto 30px;
      }
      
      .search-box {
        display: flex;
        align-items: center;
        background: white;
        border-radius: 50px;
        padding: 5px;
        box-shadow: var(--shadow);
        border: 1px solid var(--light-gray);
        transition: var(--transition);
      }
      
      .search-box:focus-within {
        border-color: var(--primary-color);
        box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.2);
      }
      
      .search-icon {
        width: 24px;
        height: 24px;
        fill: var(--gray-color);
        margin: 0 15px;
      }
      
      .search-input {
        flex: 1;
        border: none;
        outline: none;
        padding: 15px 0;
        font-size: 1rem;
        background: transparent;
      }
      
      .search-button {
        background: var(--primary-color);
        color: white;
        border: none;
        border-radius: 50px;
        padding: 15px 30px;
        font-size: 1rem;
        font-weight: 600;
        cursor: pointer;
        transition: var(--transition);
      }
      
      .search-button:hover {
        background: var(--primary-dark);
        transform: translateY(-2px);
      }
      
      .category-filters {
        margin-top: 20px;
      }
      
      .filter-options {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        align-items: center;
        gap: 15px;
      }
      
      .filter-label {
        font-size: 0.9rem;
        color: var(--gray-color);
        font-weight: 600;
      }
      
      .filter-buttons {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 10px;
      }
      
      .filter-btn {
        background: white;
        border: 1px solid var(--light-gray);
        border-radius: 20px;
        padding: 8px 18px;
        font-size: 0.9rem;
        color: var(--gray-color);
        cursor: pointer;
        transition: var(--transition);
      }
      
      .filter-btn:hover {
        background: var(--light-color);
        color: var(--dark-color);
      }
      
      .filter-btn.active {
        background: var(--primary-color);
        color: white;
        border-color: var(--primary-color);
      }
      
      .gallery-container {
        padding: 0 0 40px;
      }
      
      .gallery-grid {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
        gap: 25px;
        margin-bottom: 30px;
      }
      
      .gallery-item {
        position: relative;
        border-radius: 12px;
        overflow: hidden;
        box-shadow: var(--shadow);
        transition: var(--transition);
        background: white;
      }
      
      .gallery-item:hover {
        transform: translateY(-5px);
        box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
      }
      
      .gallery-image {
        width: 100%;
        height: 320px;
        object-fit: cover;
        display: block;
        transition: transform 0.5s ease;
      }
      
      .gallery-item:hover .gallery-image {
        transform: scale(1.05);
      }
      
      .image-overlay {
        position: absolute;
        bottom: 0;
        left: 0;
        right: 0;
        padding: 20px;
        background: linear-gradient(to top, rgba(0, 0, 0, 0.7) 0%, transparent 100%);
        color: white;
        opacity: 0;
        transition: var(--transition);
      }
      
      .gallery-item:hover .image-overlay {
        opacity: 1;
      }
      
      .image-author {
        font-size: 0.9rem;
        font-weight: 500;
        margin-bottom: 10px;
        display: block;
      }
      
      .view-btn {
        background: rgba(255, 255, 255, 0.9);
        color: var(--primary-color);
        border: none;
        border-radius: 20px;
        padding: 8px 16px;
        font-size: 0.9rem;
        font-weight: 600;
        cursor: pointer;
        transition: var(--transition);
        display: inline-flex;
        align-items: center;
        gap: 5px;
      }
      
      .view-btn:hover {
        background: white;
        transform: translateY(-2px);
      }
      
      .view-btn svg {
        width: 16px;
        height: 16px;
        fill: var(--primary-color);
      }
      
      .loading-indicator {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        padding: 30px;
        color: var(--gray-color);
        gap: 15px;
      }
      
      .spinner {
        width: 40px;
        height: 40px;
        border: 4px solid rgba(0, 0, 0, 0.1);
        border-radius: 50%;
        border-top-color: var(--primary-color);
        animation: spin 1s ease-in-out infinite;
      }
      
      @keyframes spin {
        to { transform: rotate(360deg); }
      }
      
      .image-preview-overlay {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.95);
        z-index: 1000;
        display: none;
        opacity: 0;
        transition: opacity 0.3s ease;
      }
      
      .image-preview-overlay.active {
        display: flex;
        opacity: 1;
      }
      
      .preview-container {
        width: 90%;
        max-width: 1400px;
        margin: auto;
        position: relative;
        height: 90vh;
        display: flex;
        flex-direction: column;
      }
      
      .close-preview {
        position: absolute;
        top: 10px;
        right: 10px;
        background: rgba(255, 255, 255, 0.1);
        border: none;
        width: 40px;
        height: 40px;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        z-index: 10;
        transition: var(--transition);
      }
      
      .close-preview:hover {
        background: rgba(255, 255, 255, 0.2);
        transform: rotate(90deg);
      }
      
      .close-preview svg {
        width: 24px;
        height: 24px;
        fill: white;
      }
      
      .prevuew-navigation {
        display: flex;
        height: 100%;
      }
      
      .preview-image-container {
        flex: 1;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        position: relative;
      }
      
      .preview-image {
        max-width: 100%;
        max-height: 80vh;
        object-fit: contain;
        border-radius: 8px;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
      }
      
      .image-meta {
        display: flex;
        align-items: center;
        justify-content: space-between;
        width: 100%;
        max-width: 800px;
        margin-top: 20px;
        color: white;
      }
      
      .image-author {
        font-size: 1rem;
      }
      
      .download-btn {
        display: flex;
        align-items: center;
        gap: 8px;
        background: var(--primary-color);
        color: white;
        padding: 10px 20px;
        border-radius: 30px;
        text-decoration: none;
        font-weight: 500;
        transition: var(--transition);
      }
      
      .download-btn:hover {
        background: var(--primary-dark);
        transform: translateY(-2px);
      }
      
      .download-btn svg {
        width: 18px;
        height: 18px;
        fill: white;
      }
      
      .nav-btn {
        position: absolute;
        top: 50%;
        transform: translateY(-50%);
        background: rgba(255, 255, 255, 0.1);
        border: none;
        width: 50px;
        height: 50px;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        z-index: 10;
        transition: var(--transition);
      }
      
      .nav-btn:hover {
        background: rgba(255, 255, 255, 0.2);
      }
      
      .nav-btn svg {
        width: 24px;
        height: 24px;
        fill: white;
      }
      
      .prev-btn {
        left: 20px;
      }
      
      .next-btn {
        right: 20px;
      }
      
      .thumbnail-track {
        display: flex;
        gap: 10px;
        padding: 20px 0;
        overflow-x: auto;
        margin-top: 20px;
      }
      
      .thumbnail {
        width: 80px;
        height: 60px;
        border-radius: 4px;
        object-fit: cover;
        cursor: pointer;
        opacity: 0.6;
        transition: var(--transition);
        border: 2px solid transparent;
      }
      
      .thumbnail:hover {
        opacity: 0.8;
      }
      
      .thumbnail.active {
        opacity: 1;
        border-color: var(--primary-color);
      }
      
      @media (max-width: 768px) {
        .app-header {
          padding: 20px 0;
        }
        
        .app-header h1 {
          font-size: 1.8rem;
        }
        
        .search-box {
          flex-direction: column;
          border-radius: 12px;
          padding: 15px;
        }
        
        .search-input {
          width: 100%;
          margin-bottom: 15px;
        }
        
        .search-button {
          width: 100%;
        }
        
        .gallery-grid {
          grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
          gap: 15px;
        }
        
        .gallery-image {
          height: 240px;
        }
        
        .preview-container {
          width: 95%;
          height: 95vh;
        }
        
        .nav-btn {
          width: 40px;
          height: 40px;
        }
        
        .prev-btn {
          left: 5px;
        }
        
        .next-btn {
          right: 5px;
        }
      }