/* === BLHA Blog — Dark Tech Theme === */

:root {
    --bg-primary: #0a0a14;
    --bg-secondary: #0f0f1e;
    --bg-card: #12122a;
    --bg-card-hover: #1a1a3a;
    --bg-elevated: #16163a;
    --border: #1e1e4a;
    --border-hover: #2a2a5a;
    --text-primary: #e8e8f0;
    --text-secondary: #8888aa;
    --text-muted: #555577;
    --cyan: #00e5ff;
    --purple: #b388ff;
    --green: #69f0ae;
    --red: #ff5252;
    --gradient: linear-gradient(135deg, #00e5ff, #b388ff);
    --gradient-subtle: linear-gradient(135deg, #00e5ff20, #b388ff20);
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Cascadia Code', 'Fira Code', monospace;
    --max-width: 1200px;
    --radius: 12px;
    --radius-sm: 8px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    min-height: 100vh;
}

a { color: var(--cyan); text-decoration: none; transition: opacity 0.2s; }
a:hover { opacity: 0.8; }

ul { list-style: none; }

/* === Navbar === */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 1rem 0;
    transition: all 0.3s ease;
    background: transparent;
}

.navbar.scrolled {
    background: rgba(10, 10, 20, 0.92);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    padding: 0.6rem 0;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--text-primary);
}
.nav-logo:hover { opacity: 1; color: var(--text-primary); }

.logo-icon {
    color: var(--cyan);
    font-size: 1.4rem;
}

.logo-accent { color: var(--cyan); }

.nav-links {
    display: flex;
    gap: 0.25rem;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    transition: all 0.2s;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--text-primary);
    background: var(--bg-card);
    opacity: 1;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s;
}

.nav-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.mobile-menu {
    display: none;
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background: rgba(10, 10, 20, 0.98);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    z-index: 99;
    padding: 1rem 2rem;
}

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

.mobile-menu a {
    display: block;
    padding: 0.75rem 0;
    color: var(--text-secondary);
    font-weight: 500;
    border-bottom: 1px solid var(--border);
}

.mobile-menu a:hover { color: var(--text-primary); }

/* === Hero === */
.hero {
    position: relative;
    padding: 10rem 2rem 6rem;
    overflow: hidden;
    min-height: 90vh;
    display: flex;
    align-items: center;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(0, 229, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 229, 255, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

.hero-bg::after {
    content: '';
    position: absolute;
    top: 20%;
    left: 50%;
    transform: translateX(-50%);
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(0, 229, 255, 0.08) 0%, rgba(179, 136, 255, 0.05) 40%, transparent 70%);
    border-radius: 50%;
    filter: blur(60px);
}

.hero-container {
    position: relative;
    z-index: 1;
    max-width: var(--max-width);
    margin: 0 auto;
    width: 100%;
}

.hero-badge {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--cyan);
    border: 1px solid rgba(0, 229, 255, 0.3);
    padding: 0.4rem 1rem;
    border-radius: 100px;
    margin-bottom: 2rem;
    letter-spacing: 0.5px;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.02em;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin-bottom: 2.5rem;
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 4rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    padding: 0.75rem 1.75rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--gradient);
    color: #000;
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
    color: #000;
}

.btn-secondary {
    background: transparent;
    color: var(--cyan);
    border: 1px solid rgba(0, 229, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(0, 229, 255, 0.1);
    border-color: var(--cyan);
    opacity: 1;
}

.hero-stats {
    display: flex;
    gap: 3rem;
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-num {
    font-family: var(--font-mono);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 0.2rem;
}

/* === Sections === */
.section {
    padding: 5rem 2rem;
}

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

.section-container {
    max-width: var(--max-width);
    margin: 0 auto;
}

.section-header {
    margin-bottom: 3rem;
}

.section-title {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.accent {
    color: var(--cyan);
    margin-right: 0.5rem;
}

.section-subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* === Featured Grid === */
.featured-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.featured-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.featured-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

.featured-large {
    grid-column: 1 / -1;
    padding: 3rem;
}

.featured-large .card-title {
    font-size: 1.6rem;
}

/* === Cards === */
.card-category {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.75rem;
}

.card-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    line-height: 1.3;
    color: var(--text-primary);
}

.card-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.card-excerpt {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.card-meta {
    display: flex;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.card-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-top: 1rem;
}

.tag {
    font-size: 0.7rem;
    padding: 0.2rem 0.6rem;
    border-radius: 100px;
    background: rgba(0, 229, 255, 0.08);
    color: var(--text-muted);
    border: 1px solid rgba(0, 229, 255, 0.15);
    font-family: var(--font-mono);
}

/* === Categories Grid === */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}

.category-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    transition: all 0.3s ease;
    text-align: center;
}

.category-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-3px);
}

.category-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.category-name {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
}

.category-desc {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.category-count {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* === Articles Grid === */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.article-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.75rem;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.article-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

/* === CTA Section === */
.cta-section {
    background: var(--bg-secondary);
}

.cta-box {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 4rem;
    display: flex;
    align-items: center;
    gap: 4rem;
}

.cta-content {
    flex: 1;
}

.cta-content h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.cta-content p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1.05rem;
}

.cta-visual {
    flex-shrink: 0;
}

.cta-score {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
}

.score-ring {
    position: relative;
    width: 140px;
    height: 140px;
}

.score-ring svg {
    width: 100%;
    height: 100%;
}

.score-value {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 2rem;
    font-weight: 700;
}

.score-value small {
    font-size: 1rem;
    color: var(--text-muted);
}

.score-label {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* === Page Header (Category) === */
.page-header {
    padding: 8rem 2rem 3rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
}

.back-link {
    display: inline-block;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
    font-family: var(--font-mono);
}

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

.page-header-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.page-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
}

.page-header-desc {
    color: var(--text-secondary);
    font-size: 1.1rem;
    max-width: 600px;
    margin-bottom: 1rem;
}

.page-header-count {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* === Article Page === */
.article-header {
    padding: 8rem 2rem 3rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
}

.article-category {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 1.5rem;
}

.article-title {
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 1rem;
    max-width: 800px;
}

.article-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    max-width: 600px;
}

.article-meta {
    display: flex;
    gap: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
    margin-bottom: 1rem;
}

.article-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.article-body {
    padding: 4rem 2rem;
}

.article-content {
    max-width: 780px;
}

.article-content h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-top: 3rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.article-content h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-top: 2rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.article-content p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 1.05rem;
    line-height: 1.8;
}

.article-content ul, .article-content ol {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
}

.article-content li {
    margin-bottom: 0.5rem;
    font-size: 1.05rem;
    line-height: 1.7;
    list-style: disc;
}

.article-content strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* === Code Blocks === */
.code-block {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    margin: 1.5rem 0;
    overflow: hidden;
}

.code-header {
    display: flex;
    align-items: center;
    padding: 0.6rem 1rem;
    background: rgba(0, 229, 255, 0.05);
    border-bottom: 1px solid var(--border);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.code-block pre {
    padding: 1.25rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    line-height: 1.6;
    color: var(--text-secondary);
    overflow-x: auto;
    white-space: pre;
}

/* === Callout === */
.callout {
    background: rgba(0, 229, 255, 0.05);
    border-left: 3px solid var(--cyan);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    padding: 1.25rem 1.5rem;
    margin: 2rem 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.callout strong {
    color: var(--cyan);
}

/* === Footer === */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 4rem 2rem 2rem;
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
}

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

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

.footer-desc {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.7;
}

.footer h4 {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.footer ul li {
    margin-bottom: 0.5rem;
}

.footer ul a {
    color: var(--text-muted);
    font-size: 0.9rem;
    transition: color 0.2s;
}

.footer ul a:hover {
    color: var(--cyan);
    opacity: 1;
}

.footer-col p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.newsletter-form {
    display: flex;
    gap: 0;
    border-radius: var(--radius-sm);
    overflow: hidden;
    border: 1px solid var(--border);
}

.newsletter-form input {
    flex: 1;
    background: var(--bg-primary);
    border: none;
    padding: 0.6rem 1rem;
    color: var(--text-primary);
    font-size: 0.85rem;
    outline: none;
    font-family: var(--font-sans);
}

.newsletter-form input::placeholder {
    color: var(--text-muted);
}

.newsletter-form button {
    background: var(--cyan);
    color: #000;
    border: none;
    padding: 0.6rem 1rem;
    font-weight: 600;
    font-size: 0.85rem;
    cursor: pointer;
    font-family: var(--font-sans);
    transition: opacity 0.2s;
}

.newsletter-form button:hover {
    opacity: 0.8;
}

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 1.5rem;
    text-align: center;
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* === Responsive === */
@media (max-width: 1024px) {
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .articles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    .cta-box {
        flex-direction: column;
        text-align: center;
        padding: 3rem;
    }
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-toggle { display: flex; }

    .hero {
        padding: 7rem 1.5rem 4rem;
        min-height: auto;
    }

    .hero-stats {
        gap: 2rem;
    }

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

    .featured-large {
        padding: 2rem;
    }

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

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

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

    .section {
        padding: 3rem 1.5rem;
    }

    .cta-box {
        padding: 2rem;
    }

    .page-header {
        padding: 6rem 1.5rem 2rem;
    }

    .article-header {
        padding: 6rem 1.5rem 2rem;
    }

    .article-body {
        padding: 2rem 1.5rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .btn {
        justify-content: center;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1rem;
    }
}

/* === Selection === */
::selection {
    background: rgba(0, 229, 255, 0.2);
    color: var(--text-primary);
}

/* === Scrollbar === */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--border-hover);
}