/* ---
Ultra-Clean Professional Design System
Based on 2024-2025 Design Trends Research
--- */

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

:root {
    /* Ultra-refined color palette */
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --surface-secondary: #f5f5f7;
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-tertiary: #86868b;
    --accent: #007aff;
    --accent-hover: #0056cc;
    --accent-subtle: #f0f4ff;
    --border: #d2d2d7;
    --border-color: #d2d2d7;
    --header-bg: rgba(255, 255, 255, 0.85);
    --footer-bg: #f5f5f7;
    --footer-text: #6e6e73;
    
    /* Professional typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* Refined spacing system */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    --space-3xl: 6rem;
    
    /* Layout spacing */
    --section-padding: 4rem;
    --header-height: 80px;
    
    /* Smooth transitions */
    --transition-fast: 0.15s ease-out;
    --transition-base: 0.25s ease-out;
    --transition-slow: 0.4s ease-out;
    
    /* Border radius */
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --border-radius-xl: 16px;
    
    /* Shadows */
    --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);
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #1c1c1e;
        --bg-secondary: #2c2c2e;
        --surface-secondary: #3a3a3c;
        --text-primary: #f2f2f7;
        --text-secondary: #98989d;
        --text-tertiary: #636366;
        --accent: #0a84ff;
        --accent-hover: #409cff;
        --accent-subtle: #1a1a2e;
        --border: #38383a;
        --border-color: #38383a;
        --header-bg: rgba(28, 28, 30, 0.85);
        --footer-bg: #2c2c2e;
        --footer-text: #98989d;
    }
}

/* Base styles */
html {
    font-size: 16px;
    line-height: 1.6;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-weight: 400;
    overflow-x: hidden;
}

/* Typography System */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    color: var(--text-primary);
    margin-bottom: var(--space-md);
}

h1 { font-size: clamp(2rem, 5vw, 4rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); letter-spacing: -0.01em; }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h4 { font-size: 1.125rem; }

p, ul, ol {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    max-width: 65ch;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: opacity var(--transition-fast);
}

a:hover {
    opacity: 0.7;
}

/* Layout System */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--space-md);
    }
}

/* Header */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--header-bg);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: transform var(--transition-base);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.logo {
    font-family: var(--font-mono);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

/* Audio Section */
.audio-section {
    position: relative;
    display: flex;
    align-items: center;
}

.audio-controls {
    position: relative;
}

.audio-toggle {
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.audio-toggle:hover {
    background: var(--surface-secondary);
    color: var(--accent);
}

.audio-icon {
    width: 20px;
    height: 20px;
}

.audio-player {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    margin-top: 8px;
    background: var(--surface-primary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: 1001;
}

.audio-player.show {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.audio-player iframe {
    border-radius: 8px;
    width: 300px;
    height: 120px;
}

/* Responsive adjustments for audio */
@media (max-width: 768px) {
    .audio-player {
        left: -100px;
        transform: none;
        width: 280px;
    }
    
    .audio-player.show {
        transform: none;
    }
    
    .audio-player iframe {
        width: 280px;
        height: 100px;
    }
}

.nav {
    display: flex;
    gap: var(--space-lg);
}

.nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color var(--transition-fast);
    position: relative;
}

.nav a:hover {
    color: var(--accent);
}

.nav a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width var(--transition-fast);
}

.nav a:hover::after {
    width: 100%;
}

@media (max-width: 768px) {
    .header-content {
        padding: 0 var(--space-md);
    }
    
    .nav {
        gap: var(--space-md);
    }
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: var(--space-3xl) 0;
}

.hero-content {
    max-width: 800px;
}

.hero h1 {
    margin-bottom: var(--space-lg);
    font-weight: 700;
}

.hero p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
    max-width: none;
}

.hero-meta {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    margin-bottom: var(--space-md);
}

/* Sections */
.section {
    padding: var(--space-3xl) 0;
}

.section-header {
    margin-bottom: var(--space-2xl);
}

.section-title {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-sm);
}

.section h2 {
    margin-bottom: var(--space-md);
}

.section p {
    font-size: 1.125rem;
    max-width: 600px;
}

/* Grid System */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-xl);
    margin-top: var(--space-2xl);
}

@media (max-width: 768px) {
    .grid {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
}

/* Cards */
.card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    padding: var(--space-xl);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
    border-color: var(--accent);
}

.card h3 {
    margin-bottom: var(--space-md);
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.1rem;
}

.card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-hover));
    transform: scaleX(0);
    transition: transform var(--transition-base);
}

.card:hover::before {
    transform: scaleX(1);
}

/* Code blocks */
pre {
    background: var(--accent-subtle);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: var(--space-md);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.5;
    margin: var(--space-md) 0;
}

code {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-primary);
}

/* Blockquotes */
blockquote {
    border-left: 2px solid var(--accent);
    padding-left: var(--space-md);
    margin: var(--space-lg) 0;
    font-style: italic;
    color: var(--text-secondary);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    background: var(--accent);
    color: var(--bg-primary);
    border: 1px solid var(--accent);
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all var(--transition-fast);
    cursor: pointer;
}

.btn:hover {
    background: transparent;
    color: var(--accent);
    opacity: 1;
}

.btn-outline {
    background: transparent;
    color: var(--accent);
}

.btn-outline:hover {
    background: var(--accent);
    color: var(--bg-primary);
}

/* Footer */
footer {
    border-top: 1px solid var(--border);
    padding: var(--space-xl) 0;
    text-align: center;
}

footer p {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-tertiary);
    margin: 0;
}

/* Utilities */
.text-center { text-align: center; }
.text-mono { font-family: var(--font-mono); }
.text-sm { font-size: 0.875rem; }
.text-lg { font-size: 1.125rem; }

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

.animate-fade-in {
    animation: fadeInUp 0.6s ease-out;
}

/* Responsive refinements */
@media (max-width: 480px) {
    .hero {
        padding: var(--space-2xl) 0;
    }
    
    .section {
        padding: var(--space-2xl) 0;
    }
    
    .card {
        padding: var(--space-lg);
    }
} 

/* Section spacing improvements */
.section {
    padding: var(--section-padding) 0;
    margin-bottom: var(--space-xl);
}

.section + .section {
    margin-top: var(--space-xl);
}

/* Demo section button spacing */
.section .text-center {
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
}

/* Legacy page styles for compatibility */
.main-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
    padding-top: calc(var(--header-height) + var(--space-xl));
}

.content-page-header {
    text-align: center;
    padding: var(--space-xl) 0;
    margin-bottom: var(--space-xl);
}

.content-page-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-md);
}

.content-page-header h2 {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.content-page-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto var(--space-md);
    line-height: 1.6;
}

/* Legacy section styles */
.main-container .section {
    margin-bottom: var(--space-xl);
    padding: var(--space-lg) 0;
}

.main-container .section h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-md);
}

.main-container .section p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-md);
}

.main-container .section ul {
    margin-left: var(--space-md);
    margin-bottom: var(--space-md);
}

.main-container .section li {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-sm);
}

.main-container .section strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* Footer improvements */
footer {
    background-color: var(--footer-bg);
    border-top: 1px solid var(--border-color);
    padding: var(--space-xl) 0;
    margin-top: var(--space-xl);
}

footer p {
    color: var(--footer-text);
    font-size: 0.9rem;
    text-align: center;
    margin: 0;
    font-weight: 500;
} 

/* Text alignment utilities */
.text-center { 
    text-align: center; 
}

.text-center h2,
.text-center .section-title,
.text-center p {
    text-align: center;
}

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

.section-header.text-center .section-title {
    text-align: center;
}

.section-header.text-center h2 {
    text-align: center;
}

.section-header.text-center p {
    text-align: center;
    margin-left: auto;
    margin-right: auto;
}

/* Improved section spacing */
.section {
    padding: var(--section-padding) 0;
}

.section + .section {
    margin-top: var(--space-2xl);
}

/* Button spacing improvements */
.btn {
    display: inline-block;
    padding: var(--space-md) var(--space-xl);
    background-color: var(--accent);
    color: var(--bg-secondary);
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.2s ease;
    margin-top: var(--space-lg);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3);
}

.text-center .btn {
    margin-top: var(--space-xl);
}

/* Secondary button style */
.btn-secondary {
    display: inline-block;
    padding: var(--space-md) var(--space-xl);
    background-color: transparent;
    color: var(--accent);
    text-decoration: none;
    border: 2px solid var(--accent);
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.2s ease;
    margin-top: var(--space-lg);
}

.btn-secondary:hover {
    background-color: var(--accent);
    color: var(--bg-secondary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3);
} 

/* Single Page Application Styles */
.page-content {
    display: none;
    opacity: 0;
    transition: opacity var(--transition-base);
}

.page-content.active {
    display: block;
    opacity: 1;
}

/* Navigation active state */
.nav a.active {
    color: var(--accent);
}

.nav a.active::after {
    width: 100%;
}

/* Content sections */
.content {
    max-width: 800px;
    margin: 0 auto;
}

.content h2 {
    margin-top: var(--space-xl);
    margin-bottom: var(--space-lg);
}

.content h3 {
    margin-top: var(--space-lg);
    margin-bottom: var(--space-md);
}

.content ul {
    padding-left: var(--space-lg);
}

.content li {
    margin-bottom: var(--space-sm);
}

/* Contact section */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    margin-top: var(--space-xl);
}

.contact-info h3,
.cta-section h3 {
    margin-bottom: var(--space-md);
}

.contact-info p,
.cta-section p {
    margin-bottom: var(--space-md);
}

@media (max-width: 768px) {
    .contact-content {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
} 

/* Blog Actions */
.blog-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    flex-wrap: wrap;
}

.share-buttons {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-left: auto;
}

.share-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
}

.btn-share {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    border-radius: 0.5rem;
    transition: all 0.2s ease;
    text-decoration: none;
    border: 1px solid var(--border-color);
    background: transparent;
    color: var(--text-color);
}

.btn-share:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.twitter-share:hover {
    background: #1da1f2;
    color: white;
    border-color: #1da1f2;
}

.linkedin-share:hover {
    background: #0077b5;
    color: white;
    border-color: #0077b5;
}

.copy-link-btn {
    cursor: pointer;
}

.copy-link-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.copy-link-btn.copied {
    background: #10b981 !important;
    color: white !important;
    border-color: #10b981 !important;
}

/* Timeline Card Improvements */
.timeline-card {
    position: relative;
    transition: all 0.3s ease;
}

.timeline-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.timeline-subtitle {
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.timeline-readmore {
    margin-top: 1rem;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .blog-actions {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .share-buttons {
        margin-left: 0;
        flex-wrap: wrap;
    }
    
    .btn-share {
        font-size: 0.75rem;
        padding: 0.375rem 0.75rem;
    }
}