/**
 * SEO & Performance Optimization Styles
 * All Star Tower Defense X Tier List
 * Version: 2.1.0
 * Last Updated: July 21, 2025
 */

/* ===== CRITICAL ABOVE-THE-FOLD STYLES ===== */

/* Navigation Critical Styles */
.nav-critical {
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 50;
}

/* Hero Section Critical Styles */
.hero-critical {
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
    color: white;
    padding: 5rem 0;
    text-align: center;
}

/* Tier Overview Critical Styles */
.tier-overview-critical {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 3rem 0;
}

/* ===== PERFORMANCE OPTIMIZATIONS ===== */

/* Reduce Layout Shifts */
.tier-card-skeleton {
    min-height: 200px;
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

@keyframes loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* Image Loading Optimization */
.img-lazy {
    opacity: 0;
    transition: opacity 0.3s;
}

.img-lazy.loaded {
    opacity: 1;
}

/* Preload Critical Resources */
.preload-hint {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ===== SEO STRUCTURED DATA STYLES ===== */

/* Breadcrumb Schema Styles */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin: 1rem 0;
    font-size: 0.875rem;
    color: #6b7280;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
}

.breadcrumb-separator {
    margin: 0 0.5rem;
    color: #9ca3af;
}

/* Article/Content Schema Styles */
.article-header {
    margin-bottom: 2rem;
}

.article-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin: 1rem 0;
    font-size: 0.875rem;
    color: #6b7280;
}

.article-author {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.article-date {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Rating Schema Styles */
.rating-display {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.star-rating {
    display: flex;
    gap: 0.125rem;
}

.star {
    color: #fbbf24;
    font-size: 1rem;
}

.star.empty {
    color: #d1d5db;
}

/* ===== ACCESSIBILITY ENHANCEMENTS ===== */

/* Focus Styles */
.focus-visible:focus {
    outline: 2px solid #3b82f6;
    outline-offset: 2px;
}

/* Screen Reader Only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    .tier-s,
    .tier-a,
    .tier-b,
    .tier-c,
    .tier-d {
        border: 2px solid currentColor;
    }
    
    .btn {
        border: 2px solid currentColor;
    }
}

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

/* ===== MOBILE PERFORMANCE ===== */

/* Touch Optimization */
@media (hover: none) and (pointer: coarse) {
    .tier-card:hover {
        transform: none;
    }
    
    .card:hover {
        transform: none;
    }
    
    /* Larger touch targets */
    .btn,
    .nav-link {
        min-height: 44px;
        min-width: 44px;
    }
}

/* ===== CRITICAL CSS INLINING HELPERS ===== */

/* Above-the-fold content styles that should be inlined */
.critical-nav {
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
    position: sticky;
    top: 0;
    z-index: 50;
}

.critical-hero {
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
    color: white;
    padding: 5rem 1rem;
    text-align: center;
}

.critical-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.critical-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    max-width: 48rem;
    margin: 0 auto;
}

/* ===== FONT LOADING OPTIMIZATION ===== */

/* Font Display Swap for Performance */
@font-face {
    font-family: 'FontAwesome';
    font-display: swap;
}

/* Fallback Font Stack */
.font-fallback {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

/* ===== CONTENT VISIBILITY OPTIMIZATION ===== */

/* Lazy Load Sections */
.lazy-section {
    content-visibility: auto;
    contain-intrinsic-size: 500px;
}

/* ===== PRINT OPTIMIZATION ===== */

@media print {
    /* Hide non-essential elements */
    .no-print {
        display: none !important;
    }
    
    /* Optimize colors for print */
    .tier-s,
    .tier-a,
    .tier-b,
    .tier-c,
    .tier-d {
        background: white !important;
        color: black !important;
        border: 2px solid black !important;
    }
    
    /* Page breaks */
    .page-break-before {
        page-break-before: always;
    }
    
    .page-break-after {
        page-break-after: always;
    }
    
    .page-break-inside-avoid {
        page-break-inside: avoid;
    }
}

/* ===== DARK MODE SUPPORT ===== */

@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #1f2937;
        --bg-secondary: #111827;
        --text-primary: #f9fafb;
        --text-secondary: #d1d5db;
    }
    
    body {
        background-color: var(--bg-primary);
        color: var(--text-primary);
    }
    
    .card {
        background-color: var(--bg-secondary);
        color: var(--text-primary);
    }
}

/* ===== CONTAINER QUERIES (Future-proofing) ===== */

@container (min-width: 768px) {
    .tier-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@container (min-width: 1024px) {
    .tier-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}