/* Base styles */
:root {
    --primary-color: #8B5CF6;
    --primary-dark: #7C3AED;
    --primary-light: #A78BFA;
    --secondary-color: #EC4899;
    --secondary-dark: #DB2777;
    --accent-color: #F59E0B;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --background: #F8FAFC;
    --card-bg: rgba(255, 255, 255, 0.9);
    --success: #10B981;
    --warning: #F59E0B;
    --error: #EF4444;
    
    --shadow-sm: 0 2px 4px 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);
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 9999px;
}

/* Global styles */
body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    padding: 0;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
}

/* App Header */
.app-header {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    padding: var(--spacing-md);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.back-button {
    color: white;
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: opacity 0.3s ease;
}

.back-button:hover {
    opacity: 0.8;
}

/* App Hero Section */
.app-hero {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    padding: var(--spacing-xl) var(--spacing-md);
    text-align: center;
    position: relative;
    overflow: hidden;
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.app-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" fill="none"/><path d="M50 10 L90 90 L10 90 Z" stroke="rgba(255,255,255,0.1)" stroke-width="2" fill="none"/></svg>') repeat;
    opacity: 0.1;
    animation: rotate 20s linear infinite;
}

.app-icon-large {
    font-size: 5rem;
    margin-bottom: var(--spacing-md);
    display: inline-block;
    animation: float 3s ease-in-out infinite;
}

.app-info {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.app-info h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: var(--spacing-md);
    animation: fadeInUp 1s ease-out;
}

.app-tagline {
    font-size: clamp(1rem, 2vw, 1.25rem);
    opacity: 0.9;
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 1s ease-out 0.2s backwards;
}

.platform-badges {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 1s ease-out 0.3s backwards;
}

.platform-badge {
    background: rgba(255, 255, 255, 0.1);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.platform-badge:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.app-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 1s ease-out 0.4s backwards;
}

.download-btn-large, .preview-btn {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border: none;
    padding: 16px 32px;
    border-radius: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 12px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
    font-size: 1.1rem;
}

.download-btn-large:hover, .preview-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(139, 92, 246, 0.4);
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
}

.download-btn-large:active, .preview-btn:active {
    transform: translateY(1px);
    box-shadow: 0 2px 10px rgba(139, 92, 246, 0.3);
}

.download-btn-large i, .preview-btn i {
    font-size: 1.4rem;
    transition: transform 0.3s ease;
}

.download-btn-large:hover i, .preview-btn:hover i {
    transform: translateY(-2px);
}

.btn-subtitle {
    display: flex;
    flex-direction: column;
    font-size: 0.85rem;
    margin-left: 8px;
    line-height: 1.3;
    text-align: left;
}

.btn-subtitle::before {
    content: '📱';
    font-size: 1rem;
    margin-right: 4px;
}

.download-progress {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    display: none;
    border-radius: 0 0 12px 12px;
    overflow: hidden;
}

.download-progress.active {
    display: block;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--success), #45a049);
    width: 0;
    transition: width 0.3s ease;
    position: relative;
    overflow: hidden;
}

.progress-bar::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.2),
        transparent
    );
    animation: progress-shine 1.5s infinite;
}

@keyframes progress-shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

/* Touch Device Optimizations */
@media (hover: none) {
    .download-btn-large:active, .preview-btn:active {
        transform: scale(0.98);
    }

    .download-btn-large i:active, .preview-btn i:active {
        transform: scale(0.95);
    }
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .download-btn-large, .preview-btn {
        padding: 14px 28px;
        font-size: 1rem;
        border-radius: 10px;
    }

    .btn-subtitle {
        font-size: 0.8rem;
    }
}

.tech-info {
    font-size: 0.875rem;
    opacity: 0.8;
    animation: fadeInUp 1s ease-out 0.5s backwards;
}

/* Screenshots Section */
.app-screenshots {
    padding: var(--spacing-xl) var(--spacing-md);
}

.app-screenshots h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    font-size: 2rem;
}

.screenshot-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.screenshot-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

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

.screenshot {
    width: 100%;
    height: auto;
    display: block;
}

.screenshot-caption {
    padding: var(--spacing-sm);
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Features Section */
.app-features {
    padding: var(--spacing-xl) var(--spacing-md);
    background: linear-gradient(to bottom, var(--background), white);
}

.app-features h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    font-size: 2rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.feature-item {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid rgba(0, 0, 0, 0.1);
}

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

.feature-icon {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.feature-item h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

/* Technical Details Section */
.technical-details {
    padding: var(--spacing-xl) var(--spacing-md);
}

.technical-details h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    font-size: 2rem;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.tech-item {
    background: var(--card-bg);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.tech-item h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tech-table {
    width: 100%;
    border-collapse: collapse;
}

.tech-table td {
    padding: var(--spacing-sm);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.tech-table code {
    background: #1E293B;
    color: white;
    padding: 0.2rem 0.4rem;
    border-radius: var(--radius-sm);
    font-family: 'Courier New', Courier, monospace;
}

.tech-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.tech-list li {
    padding: var(--spacing-sm) 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Contribution Section */
.contribution {
    padding: var(--spacing-xl) var(--spacing-md);
    background: linear-gradient(to bottom, white, var(--background));
}

.contribution h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    font-size: 2rem;
}

.contribution-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.contribution-steps {
    list-style: none;
    padding: 0;
    margin: var(--spacing-lg) 0;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.contribution-steps li {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    justify-content: center;
}

.github-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: #1E293B;
    color: white;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    transition: all 0.3s ease;
}

.github-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* Footer */
.app-footer {
    background: var(--primary-dark);
    color: white;
    padding: var(--spacing-xl) var(--spacing-md);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

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

.footer-section h3 {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: var(--spacing-sm);
}

.footer-bottom {
    text-align: center;
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* Animations */
@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
    100% { transform: translateY(0px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .screenshot-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .tech-grid {
        grid-template-columns: 1fr;
    }
    
    .app-actions {
        flex-direction: column;
    }
    
    .platform-badges {
        flex-wrap: wrap;
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}