/* ========================================
   QUANTUM SPACE - Main Stylesheet
   ======================================== */

/* CSS Variables */
:root {
    --bg-primary: #1E2E56;
    --bg-secondary: #263B6A;
    --bg-card: #2A4175;
    --text-primary: #28D7F7;
    --text-secondary: #E8EEF7;
    --accent: #1FB6D8;
    --accent-hover: #28D7F7;
    --border-color: rgba(40, 215, 247, 0.2);
    --shadow: rgba(0, 0, 0, 0.3);
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

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

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: var(--text-primary);
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 0.5em;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1em;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header */
.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo img {
    height: 50px;
    width: auto;
}

.logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}

.logo-quantum {
    font-size: 1.1rem;
    color: var(--text-primary);
}

.logo-space {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 400;
}

/* Navigation */
.nav {
    display: flex;
    gap: 0.5rem;
}

.nav a {
    padding: 0.5rem 1rem;
    color: var(--text-secondary);
    border-radius: 6px;
    transition: all 0.2s ease;
    font-size: 0.95rem;
}

.nav a:hover,
.nav a.active {
    background: var(--bg-card);
    color: var(--text-primary);
}

/* Mobile menu */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
}

/* Hero Section */
.hero {
    padding: 4rem 0;
    text-align: center;
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-badge {
    display: inline-block;
    background: var(--bg-card);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    color: var(--accent);
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 2rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 500;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    text-decoration: none;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    color: var(--bg-primary);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-card);
    color: var(--text-primary);
    border-color: var(--accent);
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* Sections */
.section {
    padding: 4rem 0;
}

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

.section-title {
    text-align: center;
    margin-bottom: 2.5rem;
}

.section-title h2 {
    margin-bottom: 0.5rem;
}

.section-title p {
    color: var(--text-secondary);
    opacity: 0.8;
}

/* Episode Cards Grid */
.episodes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 1.5rem;
}

/* Episode Card */
.episode-card {
    background: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.episode-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent);
    box-shadow: 0 10px 30px var(--shadow);
}

.episode-card-image {
    position: relative;
    aspect-ratio: 16/9;
    overflow: hidden;
}

.episode-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

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

.episode-number {
    position: absolute;
    top: 0.75rem;
    left: 0.75rem;
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-weight: 600;
    font-size: 0.85rem;
}

.episode-card-content {
    padding: 1.25rem;
}

.episode-card-date {
    font-size: 0.85rem;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.episode-card h3 {
    font-size: 1.15rem;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.episode-card-summary {
    font-size: 0.95rem;
    color: var(--text-secondary);
    opacity: 0.85;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.episode-guest {
    font-size: 0.9rem;
    color: var(--accent);
    margin-bottom: 0.75rem;
    padding: 0.4rem 0.6rem;
    background: rgba(40, 215, 247, 0.1);
    border-radius: 4px;
    display: inline-block;
}

.episode-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tag {
    background: rgba(31, 182, 216, 0.15);
    color: var(--accent);
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 500;
}

.episode-card-actions {
    display: flex;
    gap: 0.75rem;
}

/* Featured Episode */
.featured-episode {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 2rem;
    align-items: center;
    background: var(--bg-card);
    border-radius: 16px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    margin-bottom: 3rem;
}

.featured-episode-image {
    aspect-ratio: 16/9;
    overflow: hidden;
}

.featured-episode-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.featured-episode-content {
    padding: 2rem;
}

.featured-badge {
    display: inline-block;
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

/* Filter Chips */
.filter-section {
    margin-bottom: 2rem;
}

.filter-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.filter-chip {
    background: var(--bg-card);
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    cursor: pointer;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.filter-chip:hover,
.filter-chip.active {
    background: var(--accent);
    color: var(--bg-primary);
    border-color: var(--accent);
}

/* Info Section */
.info-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: start;
}

.info-block h2 {
    margin-bottom: 1rem;
}

.info-block p {
    font-size: 1.05rem;
    opacity: 0.9;
}

.info-list {
    list-style: none;
}

.info-list li {
    padding: 0.75rem 0;
    padding-left: 1.5rem;
    position: relative;
    border-bottom: 1px solid var(--border-color);
}

.info-list li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--accent);
}

.info-list li:last-child {
    border-bottom: none;
}

/* Page Header */
.page-header {
    padding: 3rem 0;
    background: var(--bg-secondary);
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.page-header h1 {
    margin-bottom: 0.5rem;
}

.page-header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    opacity: 0.85;
    max-width: 600px;
    margin: 0 auto;
}

/* Episode Detail */
.episode-detail {
    padding: 3rem 0;
}

.episode-hero {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.episode-video-container {
    background: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.episode-video-container img {
    width: 100%;
    aspect-ratio: 16/9;
    object-fit: cover;
}

.video-overlay {
    padding: 1.5rem;
    text-align: center;
}

.episode-meta {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.episode-info-box {
    background: var(--bg-card);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.episode-info-box h4 {
    margin-bottom: 0.75rem;
    font-size: 1rem;
}

.episode-content-section {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 2rem;
}

.episode-content-section h3 {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.concept-list {
    list-style: none;
}

.concept-list li {
    padding: 0.75rem 0;
    padding-left: 1.5rem;
    position: relative;
    border-bottom: 1px solid var(--border-color);
}

.concept-list li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--accent);
    font-size: 1.5rem;
    line-height: 1;
}

.concept-list li:last-child {
    border-bottom: none;
}

/* Resources List */
.resources-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.resource-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-card);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.resource-item:hover {
    border-color: var(--accent);
    transform: translateX(4px);
}

.resource-type {
    background: rgba(31, 182, 216, 0.15);
    color: var(--accent);
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    white-space: nowrap;
}

.resource-title {
    flex: 1;
    color: var(--text-secondary);
}

.resource-arrow {
    color: var(--accent);
}

/* Glossary */
.glossary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
}

.glossary-item {
    background: var(--bg-card);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.glossary-term {
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.glossary-def {
    font-size: 0.9rem;
    opacity: 0.85;
}

/* Deep Dives Grid */
.deepdive-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.deepdive-card {
    background: var(--bg-card);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.deepdive-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent);
}

.deepdive-card h3 {
    margin-bottom: 0.75rem;
}

.deepdive-card p {
    font-size: 0.95rem;
    opacity: 0.85;
    margin-bottom: 1rem;
}

/* Book Page */
.book-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 3rem;
    align-items: start;
}

.book-cover {
    background: var(--bg-card);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    text-align: center;
}

.book-cover img {
    border-radius: 8px;
    box-shadow: 0 10px 30px var(--shadow);
    margin-bottom: 1rem;
}

.book-content h2 {
    margin-top: 1.5rem;
}

.book-content h2:first-child {
    margin-top: 0;
}

.book-list {
    list-style: none;
}

.book-list li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.book-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* About Page */
.about-layout {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 3rem;
    align-items: start;
}

.about-photo {
    text-align: center;
}

.about-photo img {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--accent);
    margin-bottom: 1rem;
}

.about-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

/* Disclaimer */
.disclaimer {
    background: rgba(31, 182, 216, 0.1);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem 1.5rem;
    font-size: 0.9rem;
    margin-top: 2rem;
}

.disclaimer-title {
    color: var(--accent);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    margin-top: auto;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

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

.footer-copy {
    font-size: 0.85rem;
    opacity: 0.7;
}

/* Breadcrumb */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    opacity: 0.8;
}

.breadcrumb a {
    color: var(--text-secondary);
}

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

.breadcrumb-separator {
    color: var(--accent);
}

/* Related Episodes */
.related-episodes {
    margin-top: 2rem;
}

.related-episodes h4 {
    margin-bottom: 1rem;
}

.related-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.related-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.75rem;
    background: var(--bg-card);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.related-item:hover {
    border-color: var(--accent);
}

.related-item-thumb {
    width: 80px;
    height: 45px;
    object-fit: cover;
    border-radius: 4px;
}

.related-item-info {
    flex: 1;
}

.related-item-title {
    font-size: 0.9rem;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.related-item-date {
    font-size: 0.8rem;
    color: var(--accent);
}

/* Back link */
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.back-link:hover {
    color: var(--accent);
}

/* Loading state */
.loading {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

/* Empty state */
.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.empty-state h3 {
    margin-bottom: 0.5rem;
}

/* Responsive */
@media (max-width: 992px) {
    .featured-episode {
        grid-template-columns: 1fr;
    }

    .episode-hero {
        grid-template-columns: 1fr;
    }

    .info-section {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .book-layout {
        grid-template-columns: 1fr;
    }

    .book-cover {
        max-width: 300px;
        margin: 0 auto;
    }

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

    .about-photo {
        margin: 0 auto;
    }
}

@media (max-width: 768px) {
    .header-inner {
        flex-wrap: wrap;
    }

    .menu-toggle {
        display: block;
    }

    .nav {
        display: none;
        width: 100%;
        flex-direction: column;
        padding-top: 1rem;
        border-top: 1px solid var(--border-color);
        margin-top: 1rem;
    }

    .nav.active {
        display: flex;
    }

    .nav a {
        padding: 0.75rem;
        text-align: center;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }

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

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

    .footer-links {
        flex-direction: column;
        gap: 0.75rem;
    }

    h1 { font-size: 1.75rem; }
    h2 { font-size: 1.5rem; }

    .episode-card-actions {
        flex-direction: column;
    }
}

/* Print styles */
@media print {
    .header, .footer, .btn, .filter-section {
        display: none;
    }

    body {
        background: white;
        color: black;
    }

    a {
        color: black;
    }
}