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

:root {
    --primary-color: #165DFF;
    --primary-hover: #0E42D2;
    --secondary-color: #6B7280;
    --accent-color: #FF6B35;
    --background-color: #F8FAFC;
    --card-background: #FFFFFF;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --border-color: #E2E8F0;
    --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);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 1rem 2rem;
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-color);
}

/* Main Content */
.main-content {
    padding-top: 100px;
    min-height: 100vh;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 0 4rem;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Filter Section */
.filter-section {
    margin-bottom: 3rem;
}

.filter-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.filter-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.filter-tag {
    padding: 0.5rem 1.25rem;
    background: var(--card-background);
    border: 2px solid var(--border-color);
    border-radius: 50px;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: var(--transition);
}

.filter-tag:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.filter-tag.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
}

/* App Grid */
.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

/* App Card */
.app-card {
    background: var(--card-background);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    cursor: pointer;
    border: 1px solid transparent;
}

.app-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.app-card.featured {
    background: linear-gradient(135deg, #FFF5F5 0%, #FFFFFF 100%);
    border: 2px solid var(--accent-color);
    position: relative;
}

.app-card.featured::before {
    content: '⭐ Featured';
    position: absolute;
    top: -12px;
    right: 20px;
    background: var(--accent-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
}

.app-header {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.app-logo {
    width: 70px;
    height: 70px;
    border-radius: var(--radius-md);
    object-fit: cover;
    flex-shrink: 0;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
}

.app-logo img {
    width: 100%;
    height: 100%;
    border-radius: var(--radius-md);
    object-fit: cover;
}

.app-info {
    flex: 1;
}

.app-name {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.app-category {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.app-rating {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.stars {
    color: #F59E0B;
}

.app-description {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.app-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.app-tag {
    background: var(--background-color);
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.app-actions {
    display: flex;
    gap: 0.75rem;
}

.btn {
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.875rem;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

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

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

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

.btn-outline:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-block {
    width: 100%;
}

/* App Detail Page */
.detail-view {
    display: none;
}

.detail-view.active {
    display: block;
}

.app-detail-header {
    display: flex;
    gap: 3rem;
    margin-bottom: 3rem;
    padding: 2rem;
    background: var(--card-background);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.app-detail-logo {
    width: 150px;
    height: 150px;
    border-radius: var(--radius-lg);
    flex-shrink: 0;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    font-weight: 700;
}

.app-detail-logo img {
    width: 100%;
    height: 100%;
    border-radius: var(--radius-lg);
    object-fit: cover;
}

.app-detail-info {
    flex: 1;
}

.app-detail-name {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
}

.app-detail-meta {
    display: flex;
    gap: 2rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
}

.app-detail-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    margin-bottom: 2rem;
    cursor: pointer;
    transition: var(--transition);
}

.back-btn:hover {
    gap: 0.75rem;
}

.app-detail-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2rem;
}

.app-detail-section {
    background: var(--card-background);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.app-detail-section h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.app-detail-description {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.platform-links {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.platform-link {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--background-color);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
}

.platform-link:hover {
    background: var(--primary-color);
    color: white;
}

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

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 2rem;
    text-align: center;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
}

.footer p {
    opacity: 0.7;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .app-detail-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .navbar {
        padding: 1rem;
    }

    .nav-links {
        display: none;
    }

    .hero h1 {
        font-size: 2rem;
    }

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

    .app-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .app-detail-header {
        flex-direction: column;
        gap: 1.5rem;
    }

    .app-detail-logo {
        width: 100px;
        height: 100px;
        font-size: 2rem;
    }

    .app-detail-name {
        font-size: 1.75rem;
    }

    .container {
        padding: 0 1rem;
    }
}

/* Loading State */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 4rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

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