/* ========================================
   Python Addiction - Main Stylesheet
   Dark Theme | Modern Clean Design
   ======================================== */

/* CSS Custom Properties (Variables) */
:root {
    /* Dark Theme Colors */
    --bg-primary: #0d0d0d;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #252525;
    --bg-card: #1f1f1f;

    /* Text Colors */
    --text-primary: #f5f5f5;
    --text-secondary: #b3b3b3;
    --text-muted: #808080;

    /* Accent Colors */
    --accent-primary: #4a9f4a;
    --accent-secondary: #3d8b3d;
    --accent-hover: #5cb85c;
    --accent-glow: rgba(74, 159, 74, 0.3);

    /* YouTube Red */
    --youtube-red: #ff0000;
    --youtube-dark: #cc0000;

    /* Borders & Shadows */
    --border-color: #333333;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 5rem;

    /* Typography */
    --font-primary: 'Segoe UI', system-ui, -apple-system, sans-serif;
    --font-heading: 'Segoe UI', system-ui, -apple-system, sans-serif;

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;

    /* Layout */
    --max-width: 1200px;
    --navbar-height: 70px;
}

/* ========================================
   Reset & Base Styles
   ======================================== */

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--navbar-height);
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

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

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

ul {
    list-style: none;
}

/* ========================================
   Typography
   ======================================== */

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.2;
    color: var(--text-primary);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(1.75rem, 3vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 2vw, 1.5rem); }

p {
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
}

strong {
    color: var(--text-primary);
}

/* ========================================
   Layout Utilities
   ======================================== */

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.section {
    padding: var(--spacing-xl) 0;
}

.section-alt {
    background-color: var(--bg-secondary);
}

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-sm);
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--accent-primary);
    margin: var(--spacing-sm) auto 0;
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--spacing-lg);
    color: var(--text-secondary);
}

/* ========================================
   Buttons
   ======================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
}

.btn-primary {
    background: var(--accent-primary);
    color: white;
    box-shadow: var(--shadow-md), 0 0 20px var(--accent-glow);
}

.btn-primary:hover {
    background: var(--accent-hover);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 30px var(--accent-glow);
}

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

.btn-youtube:hover {
    background: var(--youtube-dark);
    color: white;
    transform: translateY(-2px);
}

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

/* ========================================
   Navigation
   ======================================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--navbar-height);
    background: rgba(13, 13, 13, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all var(--transition-normal);
}

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

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-primary);
    font-weight: 700;
    font-size: 1.25rem;
}

.nav-logo:hover {
    color: var(--text-primary);
}

.logo-img {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    object-fit: cover;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    position: relative;
}

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

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Mobile Navigation Toggle */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    position: relative;
    transition: background var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: transform var(--transition-fast);
}

.hamburger::before { top: -7px; }
.hamburger::after { bottom: -7px; }

/* ========================================
   Hero Section
   ======================================== */

.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    overflow: hidden;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 80%, var(--accent-glow) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(74, 159, 74, 0.15) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: var(--spacing-md);
}

.hero-logo {
    width: 180px;
    height: 180px;
    margin: 0 auto var(--spacing-md);
    border-radius: 50%;
    box-shadow: var(--shadow-lg), 0 0 60px var(--accent-glow);
    animation: float 6s ease-in-out infinite;
}

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

.hero h1 {
    margin-bottom: var(--spacing-sm);
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.5);
}

.hero-tagline {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* ========================================
   About Section
   ======================================== */

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-text p {
    font-size: 1.1rem;
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.about-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.feature {
    text-align: center;
    padding: var(--spacing-md);
    background: var(--bg-card);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
}

.feature:hover {
    transform: translateY(-5px);
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: var(--spacing-sm);
}

.feature h3 {
    margin-bottom: var(--spacing-xs);
    color: var(--accent-primary);
}

.feature p {
    margin-bottom: 0;
    font-size: 0.95rem;
}

/* ========================================
   Expos Section
   ======================================== */

.expo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.expo-card {
    background: var(--bg-card);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    padding: var(--spacing-md);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.expo-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--accent-primary);
    transform: scaleX(0);
    transition: transform var(--transition-normal);
}

.expo-card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-lg);
}

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

.expo-date {
    display: inline-block;
    background: var(--accent-primary);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 6px;
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: var(--spacing-sm);
}

.expo-card h3 {
    margin-bottom: var(--spacing-xs);
}

.expo-time {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.expo-location {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.expo-note {
    text-align: center;
    font-style: italic;
    color: var(--text-muted);
}

/* ========================================
   YouTube Section
   ======================================== */

.youtube-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.youtube-embed {
    aspect-ratio: 16/9;
    border-radius: 12px;
    overflow: hidden;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
}

.youtube-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    text-decoration: none;
    transition: all var(--transition-normal);
}

.youtube-link:hover .youtube-placeholder {
    background: var(--bg-tertiary);
}

.youtube-link:hover .youtube-icon {
    transform: scale(1.1);
    color: var(--youtube-red);
}

.youtube-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    width: 100%;
    height: 100%;
    background: var(--bg-secondary);
    transition: background var(--transition-normal);
}

.youtube-icon {
    width: 80px;
    height: 80px;
    color: var(--text-secondary);
    transition: all var(--transition-normal);
}

.youtube-placeholder span {
    color: var(--text-secondary);
    font-weight: 500;
}

.youtube-info h3 {
    color: var(--youtube-red);
    margin-bottom: var(--spacing-sm);
    font-size: 1.5rem;
}

.youtube-info ul {
    margin: var(--spacing-md) 0;
    padding-left: var(--spacing-md);
}

.youtube-info li {
    position: relative;
    padding-left: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
    color: var(--text-secondary);
}

.youtube-info li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.6em;
    width: 6px;
    height: 6px;
    background: var(--accent-primary);
    border-radius: 50%;
}

/* ========================================
   Contact Section
   ======================================== */

.contact-content {
    max-width: 600px;
    margin: 0 auto;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.contact-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--bg-card);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.contact-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.contact-item h3 {
    margin-bottom: var(--spacing-xs);
    font-size: 1.1rem;
}

.contact-item p,
.contact-item a {
    margin-bottom: 0;
    font-size: 0.95rem;
}

/* ========================================
   Footer
   ======================================== */

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.footer-logo {
    width: 40px;
    height: 40px;
    border-radius: 50%;
}

.footer-brand p {
    margin-bottom: 0;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: var(--spacing-md);
}

.footer-links a {
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--youtube-red);
}

/* ========================================
   Responsive Design
   ======================================== */

@media (max-width: 992px) {
    .youtube-content {
        grid-template-columns: 1fr;
    }

    .youtube-embed {
        max-width: 560px;
        margin: 0 auto;
    }
}

@media (max-width: 768px) {
    :root {
        --navbar-height: 60px;
    }

    .nav-toggle {
        display: block;
    }

    .nav-menu {
        position: fixed;
        top: var(--navbar-height);
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--bg-primary);
        padding: var(--spacing-md);
        gap: 0;
        border-bottom: 1px solid var(--border-color);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-normal);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-link {
        padding: var(--spacing-sm) 0;
        width: 100%;
        text-align: center;
    }

    .logo-text {
        display: none;
    }

    .hero-logo {
        width: 140px;
        height: 140px;
    }

    .hero-tagline {
        font-size: 1.1rem;
    }

    .about-features {
        grid-template-columns: 1fr;
    }

    .expo-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .section {
        padding: var(--spacing-lg) 0;
    }

    .btn {
        width: 100%;
        padding: 1rem;
    }
}

/* ========================================
   Accessibility
   ======================================== */

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

    html {
        scroll-behavior: auto;
    }
}

/* Focus styles for accessibility */
a:focus,
button:focus {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

/* Skip to content link */
.skip-link {
    position: absolute;
    top: -100px;
    left: 0;
    background: var(--accent-primary);
    color: white;
    padding: var(--spacing-sm);
    z-index: 2000;
}

.skip-link:focus {
    top: 0;
}

/* ========================================
   Blog Page Styles
   ======================================== */

.blog-header {
    padding-top: calc(var(--navbar-height) + var(--spacing-xl));
    padding-bottom: var(--spacing-lg);
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    text-align: center;
}

.blog-header h1 {
    margin-bottom: var(--spacing-sm);
}

.blog-intro {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

.blog-grid {
    display: grid;
    gap: var(--spacing-lg);
    max-width: 800px;
    margin: 0 auto;
}

.blog-card {
    background: var(--bg-card);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: all var(--transition-normal);
    cursor: pointer;
}

.blog-card:hover {
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-3px);
}

.blog-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.blog-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.blog-card:hover .blog-image img {
    transform: scale(1.05);
}

.blog-card-content {
    padding: var(--spacing-md);
}

.blog-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    font-size: 0.85rem;
}

.blog-category {
    background: var(--accent-primary);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.5px;
}

.blog-date {
    color: var(--text-muted);
}

.blog-title {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    line-height: 1.3;
}

.blog-excerpt {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-sm);
}

.blog-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-sm);
}

.blog-tag {
    background: var(--bg-tertiary);
    color: var(--text-muted);
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.8rem;
}

.blog-full-content {
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    margin-top: var(--spacing-md);
}

.blog-full-content p {
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.blog-full-content h3 {
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    color: var(--accent-primary);
}

.blog-read-more {
    background: transparent;
    border: 1px solid var(--accent-primary);
    color: var(--accent-primary);
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.blog-read-more:hover {
    background: var(--accent-primary);
    color: white;
}

.blog-empty {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--bg-card);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.blog-empty h3 {
    margin-bottom: var(--spacing-sm);
}

.blog-video-link {
    background: var(--bg-tertiary);
    border-left: 4px solid var(--youtube-red);
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border-radius: 0 8px 8px 0;
}

.blog-video-link p {
    margin-bottom: 0;
}

.blog-video-link a {
    color: var(--youtube-red);
    font-weight: 600;
}

.blog-video-link a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .blog-header {
        padding-top: calc(var(--navbar-height) + var(--spacing-lg));
    }

    .blog-title {
        font-size: 1.25rem;
    }

    .blog-card-content {
        padding: var(--spacing-sm);
    }
}