/* Mobile-First Responsive Design for Claude Code Primer */

/* Base Mobile Styles (320px+) */
* {
    box-sizing: border-box;
    -webkit-tap-highlight-color: rgba(0,0,0,0);
}

body {
    font-family: 'Georgia', 'Times New Roman', serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    color: #333;
    background-color: #fff;
    font-size: 18px; /* Larger base font for mobile */
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
}

/* Mobile Typography */
h1 {
    font-size: 2.2em;
    line-height: 1.2;
    margin: 0.5em 0;
    font-weight: 400;
}

h2 {
    font-size: 1.8em;
    line-height: 1.3;
    margin: 0.8em 0 0.5em 0;
    font-weight: 500;
}

h3 {
    font-size: 1.4em;
    line-height: 1.4;
    margin: 0.6em 0 0.4em 0;
    font-weight: 500;
}

p {
    margin: 0 0 1.2em 0;
    line-height: 1.7;
}

/* Touch-Friendly Links */
a {
    color: #0066cc;
    text-decoration: none;
    padding: 0.2em 0;
    margin: -0.2em 0;
    min-height: 44px; /* Minimum touch target */
    display: inline-block;
    border-radius: 3px;
    transition: background-color 0.2s ease;
}

a:hover, a:focus {
    background-color: rgba(0, 102, 204, 0.1);
    text-decoration: underline;
}

/* Mobile Container */
.container {
    padding: 1rem;
    max-width: 100%;
    margin: 0 auto;
}

/* Mobile Hero Section */
.hero {
    padding: 2rem 1rem;
    text-align: center;
    background: #fff;
    border-bottom: 2px solid #333;
}

.hero h1 {
    font-size: 2.5em;
    margin: 0 0 0.5em 0;
}

.hero .subtitle {
    font-size: 1.2em;
    color: #666;
    font-style: italic;
    margin-bottom: 1.5em;
}

/* Touch-Friendly Navigation */
.mobile-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 0.5rem 1rem;
    border-bottom: 1px solid #eee;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.mobile-nav-toggle {
    background: none;
    border: none;
    font-size: 1.5em;
    padding: 0.5rem;
    min-height: 44px;
    min-width: 44px;
    cursor: pointer;
    border-radius: 4px;
}

.mobile-nav-toggle:hover {
    background-color: #f0f0f0;
}

.mobile-nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    border-bottom: 1px solid #eee;
    max-height: 50vh;
    overflow-y: auto;
}

.mobile-nav-menu.open {
    display: block;
}

.mobile-nav-item {
    display: block;
    padding: 1rem;
    border-bottom: 1px solid #f0f0f0;
    color: #333;
    text-decoration: none;
    min-height: 44px;
    font-size: 1.1em;
}

.mobile-nav-item:hover {
    background-color: #f8f9fa;
}

/* Chapter Cards - Mobile Optimized */
.chapter-card {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    display: block;
    color: inherit;
    text-decoration: none;
    border-left: 4px solid #0066cc;
    min-height: 44px;
    transition: all 0.2s ease;
}

.chapter-card:hover, .chapter-card:focus {
    background: #e9ecef;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.chapter-card h3 {
    margin: 0 0 0.5em 0;
    font-size: 1.3em;
    color: #333;
}

.chapter-card p {
    margin: 0 0 1em 0;
    color: #666;
    font-size: 0.95em;
    line-height: 1.5;
}

/* Reading Progress Indicator */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, #0066cc, #00a2ff);
    z-index: 1001;
    transition: width 0.1s ease;
}

/* Collapsible Sections */
.collapsible {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 8px;
    margin: 1rem 0;
    overflow: hidden;
}

.collapsible-header {
    background: #e9ecef;
    padding: 1rem;
    cursor: pointer;
    border: none;
    width: 100%;
    text-align: left;
    font-size: 1.1em;
    font-weight: 500;
    min-height: 44px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.collapsible-header:hover {
    background: #dee2e6;
}

.collapsible-content {
    padding: 1rem;
    display: none;
}

.collapsible-content.open {
    display: block;
}

.collapsible-arrow {
    transition: transform 0.2s ease;
}

.collapsible-arrow.open {
    transform: rotate(180deg);
}

/* Mobile-Optimized Tables */
.mobile-table {
    width: 100%;
    overflow-x: auto;
    margin: 1rem 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9em;
}

th, td {
    padding: 0.75rem 0.5rem;
    text-align: left;
    border-bottom: 1px solid #dee2e6;
    min-height: 44px;
}

th {
    background: #f8f9fa;
    font-weight: 600;
}

/* Mobile Code Blocks */
pre {
    background: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 6px;
    padding: 1rem;
    overflow-x: auto;
    font-size: 0.85em;
    line-height: 1.4;
}

code {
    background: #f1f3f4;
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-size: 0.9em;
}

/* Touch-Friendly Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    margin: 0.5rem 0.5rem 0.5rem 0;
    background: #0066cc;
    color: white;
    text-decoration: none;
    border-radius: 6px;
    border: none;
    font-size: 1rem;
    min-height: 44px;
    min-width: 44px;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: center;
}

.btn:hover, .btn:focus {
    background: #0052a3;
    transform: translateY(-1px);
}

.btn-secondary {
    background: #6c757d;
}

.btn-secondary:hover {
    background: #545b62;
}

/* Mobile Footer */
.footer {
    background: #333;
    color: white;
    padding: 2rem 1rem;
    text-align: center;
    margin-top: 3rem;
}

.footer a {
    color: #adb5bd;
    min-height: 44px;
}

/* Tablet Styles (768px+) */
@media (min-width: 768px) {
    body {
        font-size: 16px;
    }
    
    .container {
        padding: 2rem;
        max-width: 750px;
    }
    
    .hero {
        padding: 3rem 2rem;
    }
    
    .hero h1 {
        font-size: 3em;
    }
    
    .mobile-nav {
        display: none;
    }
    
    .chapter-card {
        padding: 2rem;
    }
    
    .collapsible-content {
        display: block;
    }
    
    .collapsible-header {
        cursor: default;
    }
    
    .collapsible-arrow {
        display: none;
    }
}

/* Desktop Styles (1024px+) */
@media (min-width: 1024px) {
    .container {
        max-width: 900px;
        padding: 2rem;
    }
    
    .hero h1 {
        font-size: 3.5em;
    }
    
    .chapter-card {
        display: flex;
        align-items: flex-start;
        gap: 1rem;
    }
}

/* Large Desktop (1200px+) */
@media (min-width: 1200px) {
    .container {
        max-width: 1100px;
    }
}

/* Print Styles */
@media print {
    .mobile-nav,
    .reading-progress,
    .collapsible-arrow {
        display: none;
    }
    
    .collapsible-content {
        display: block !important;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.4;
    }
    
    .chapter-card {
        break-inside: avoid;
        border: 1px solid #000;
    }
}

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

@media (prefers-color-scheme: dark) {
    body {
        background-color: #1a1a1a;
        color: #e0e0e0;
    }
    
    .hero {
        background: #1a1a1a;
        border-color: #444;
    }
    
    .chapter-card {
        background: #2a2a2a;
        border-color: #444;
        color: #e0e0e0;
    }
    
    .collapsible {
        background: #2a2a2a;
        border-color: #444;
    }
    
    .collapsible-header {
        background: #333;
    }
    
    a {
        color: #66b3ff;
    }
}

/* Focus Indicators for Accessibility */
*:focus {
    outline: 2px solid #0066cc;
    outline-offset: 2px;
}

button:focus,
a:focus {
    outline: 2px solid #0066cc;
    outline-offset: 2px;
}