/* ========================================
   Blog Blockchain Vietnam - Web3 Design System
   Theme: Dark Mode, Neon, Glassmorphism
   ======================================== */

/* Import Modern Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400&display=swap');

/* ========== CSS Variables ========== */
:root {
    /* Brand Colors - Web3 Neon */
    --primary: #8b5cf6;
    /* Violet 500 */
    --primary-hover: #7c3aed;
    /* Violet 600 */
    --secondary: #06b6d4;
    /* Cyan 500 */
    --accent: #ec4899;
    /* Pink 500 */

    /* Backgrounds */
    --bg-body: #020617;
    /* Slate 950 */
    --bg-card: rgba(30, 41, 59, 0.7);
    /* Slate 800 with opacity */
    --bg-glass: rgba(15, 23, 42, 0.6);
    /* Slate 900 with opacity */

    /* Text Colors */
    --text-main: #f8fafc;
    /* Slate 50 */
    --text-muted: #94a3b8;
    /* Slate 400 */
    --text-highlight: #e2e8f0;
    /* Slate 200 */

    /* Category Colors */
    --color-defi: #10b981;
    /* Emerald */
    --color-edu: #3b82f6;
    /* Blue */
    --color-biz: #f59e0b;
    /* Amber */
    --color-tech: #f43f5e;
    /* Rose */

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #8b5cf6 0%, #06b6d4 100%);
    --gradient-dark: linear-gradient(180deg, #020617 0%, #0f172a 100%);
    --gradient-card: linear-gradient(145deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);

    /* Effects */
    --glass-border: 1px solid rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
    --backdrop-blur: blur(12px);
    --glow: 0 0 20px rgba(139, 92, 246, 0.15);

    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-body);
    background-image:
        radial-gradient(at 0% 0%, rgba(139, 92, 246, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(6, 182, 212, 0.15) 0px, transparent 50%);
    background-attachment: fixed;
    color: var(--text-muted);
    font-size: 16px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: 'Space Grotesk', sans-serif;
    color: var(--text-main);
    line-height: 1.25;
    margin-bottom: 1rem;
}

a {
    color: var(--secondary);
    text-decoration: none;
    transition: var(--transition);
}

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

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

/* ========== Header ========== */
.modern-header {
    background: rgba(2, 6, 23, 0.8);
    backdrop-filter: var(--backdrop-blur);
    border-bottom: var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.modern-header nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    font-size: 1.75rem;
}

.logo-text {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-main);
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-muted);
    font-weight: 500;
    font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-main);
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.3);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 1.5rem;
    cursor: pointer;
}

/* ========== Hero Section ========== */
.hero-section {
    padding: 8rem 0 6rem;
    position: relative;
    overflow: hidden;
}

.hero-content {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 10;
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
}

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

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    max-width: 600px;
}

.hero-cta {
    display: flex;
    gap: 1rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 2rem;
    border-radius: 12px;
    font-weight: 600;
    font-family: 'Space Grotesk', sans-serif;
    cursor: pointer;
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 0 20px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 30px rgba(139, 92, 246, 0.5);
    color: white;
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    border: var(--glass-border);
    color: var(--text-main);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
    color: var(--text-main);
}

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

.btn-outline:hover {
    background: rgba(139, 92, 246, 0.1);
}

/* Floating Cards Animation */
.hero-image {
    position: relative;
    height: 400px;
}

.floating-card {
    position: absolute;
    background: var(--bg-card);
    backdrop-filter: var(--backdrop-blur);
    border: var(--glass-border);
    padding: 1.25rem 1.75rem;
    border-radius: 16px;
    display: flex;
    align-items: center;
    gap: 1rem;
    animation: float 4s ease-in-out infinite;
    box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.5);
}

.floating-card .card-text {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 600;
    color: var(--text-main);
}

.card-1 {
    top: 15%;
    left: 0;
    animation-delay: 0s;
    border-left: 3px solid var(--color-defi);
}

.card-2 {
    top: 45%;
    right: 0;
    animation-delay: 1.5s;
    border-left: 3px solid var(--color-tech);
}

.card-3 {
    bottom: 10%;
    left: 15%;
    animation-delay: 3s;
    border-left: 3px solid var(--color-biz);
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-20px);
    }
}

/* ========== Section Styles ========== */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.1rem;
    opacity: 0.8;
}

/* ========== Cards ========== */
.topics-grid,
.post-list,
.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.topic-card,
.post-card {
    background: var(--bg-card);
    border: var(--glass-border);
    border-radius: 20px;
    padding: 2rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.topic-card::before,
.post-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, transparent, var(--primary), transparent);
    opacity: 0;
    transition: var(--transition);
}

.topic-card:hover,
.post-card:hover {
    transform: translateY(-5px);
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.5);
}

.topic-card:hover::before,
.post-card:hover::before {
    opacity: 1;
}

.card-icon-large {
    font-size: 3rem;
    margin-bottom: 1.5rem;
}

.card-title,
.post-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.card-title a,
.post-title a {
    color: var(--text-main);
}

.card-title a:hover,
.post-title a:hover {
    color: var(--primary);
}

.card-description,
.post-excerpt {
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
    line-height: 1.7;
}

.card-link {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

/* Metadata Tags */
.post-meta {
    display: inline-block;
    font-size: 0.75rem;
    font-family: 'JetBrains Mono', monospace;
    text-transform: uppercase;
    padding: 0.25rem 0.75rem;
    border-radius: 50px;
    margin-bottom: 1rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--primary);
}

/* ========== Related Posts ========== */
.related-posts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin: 3rem 0;
}

.related-card {
    background: var(--bg-card);
    border: var(--glass-border);
    border-radius: 12px;
    padding: 1.5rem;
    transition: var(--transition);
}

.related-card:hover {
    transform: translateY(-3px);
    border-color: var(--primary);
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
}

.related-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.related-card h3 a {
    color: var(--text-main);
}

.related-card h3 a:hover {
    color: var(--primary);
}

.related-card p {
    margin: 0;
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ========== Features Grid ========== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    margin-bottom: 6rem;
}

.feature-item {
    text-align: center;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 16px;
    border: 1px solid transparent;
    transition: var(--transition);
}

.feature-item:hover {
    background: var(--bg-card);
    border-color: var(--primary);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.2));
}

/* ========== Highlights & CTA ========== */
.content-highlights {
    background: linear-gradient(180deg, rgba(139, 92, 246, 0.1) 0%, rgba(2, 6, 23, 0) 100%);
    border: var(--glass-border);
    border-radius: 24px;
    padding: 4rem;
    margin-bottom: 6rem;
}

.highlight-list {
    list-style: none;
    padding-left: 0;
}

.highlight-list li {
    padding: 0.75rem 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--text-highlight);
}

.cta-section {
    background: radial-gradient(circle at center, rgba(124, 58, 237, 0.2) 0%, rgba(2, 6, 23, 1) 70%);
    border: 1px solid var(--primary);
    border-radius: 24px;
    padding: 5rem 2rem;
    text-align: center;
    margin-bottom: 6rem;
    box-shadow: 0 0 50px -10px rgba(124, 58, 237, 0.2);
}

/* ========== Blog Index Header ========== */
.blog-index-header {
    text-align: center;
    padding: 6rem 0 4rem;
    background: linear-gradient(180deg, rgba(139, 92, 246, 0.1) 0%, transparent 100%);
    margin-bottom: 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.category-section {
    margin-bottom: 5rem;
}

.category-title {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.category-title::after {
    content: '';
    flex: 1;
    height: 1px;
    background: rgba(255, 255, 255, 0.1);
    margin-left: 1rem;
}

/* ========== Article Styling ========== */
article {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 0;
}

article img {
    max-width: 100%;
    border-radius: 12px;
    border: var(--glass-border);
    margin: 2rem 0;
}

article h2 {
    font-size: 2rem;
    margin-top: 3rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

article p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
}

article ul,
article ol {
    margin: 1.5rem 0 1.5rem 2rem;
}

article li {
    margin-bottom: 0.75rem;
}

article blockquote {
    border-left: 4px solid var(--primary);
    padding-left: 1.5rem;
    margin: 2rem 0;
    font-style: italic;
    color: var(--text-highlight);
    background: rgba(139, 92, 246, 0.1);
    padding: 1.5rem;
    border-radius: 0 12px 12px 0;
}

/* ========== About Page ========== */
.about-hero {
    text-align: center;
    padding: 6rem 0 4rem;
    position: relative;
}

.about-hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.about-hero .subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    margin-bottom: 6rem;
}

.about-text h2 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-main);
}

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    color: var(--text-muted);
}

.values-list {
    list-style: none;
    margin-top: 2rem;
    display: grid;
    gap: 1rem;
}

.values-list li {
    background: var(--bg-card);
    border: var(--glass-border);
    padding: 1rem 1.5rem;
    border-radius: 12px;
    color: var(--text-main);
    transition: var(--transition);
}

.values-list li:hover {
    border-color: var(--primary);
    transform: translateX(10px);
}

.values-list strong {
    color: var(--primary);
}

.about-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.image-placeholder {
    width: 100%;
    aspect-ratio: 1;
    background: var(--bg-card);
    border: var(--glass-border);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.image-placeholder::before {
    content: '';
    position: absolute;
    width: 150%;
    height: 150%;
    background: radial-gradient(circle at center, rgba(139, 92, 246, 0.2) 0%, transparent 60%);
    animation: pulse 4s infinite;
}

@keyframes pulse {
    0% {
        transform: scale(1);
        opacity: 0.5;
    }

    50% {
        transform: scale(1.1);
        opacity: 0.8;
    }

    100% {
        transform: scale(1);
        opacity: 0.5;
    }
}

/* Community Section */
.community-section {
    text-align: center;
    padding: 6rem 0;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.02) 0%, transparent 100%);
    border-radius: 24px;
    border: var(--glass-border);
}

.community-stats {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 3.5rem;
    font-weight: 700;
    color: white;
    font-family: 'Space Grotesk', sans-serif;
    text-shadow: 0 0 20px rgba(139, 92, 246, 0.5);
}

.stat-label {
    font-size: 1rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 0.5rem;
}

/* ========== Modern Footer ========== */
.modern-footer {
    background: #000;
    border-top: var(--glass-border);
    padding: 5rem 0 2rem;
    margin-top: auto;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 4rem;
    margin-bottom: 4rem;
}

.footer-section h4 {
    color: var(--text-main);
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
}

.footer-section p {
    color: var(--text-muted);
    line-height: 1.6;
    max-width: 300px;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.75rem;
}

.footer-section ul li a {
    color: var(--text-muted);
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: var(--primary);
    padding-left: 5px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

@media (max-width: 768px) {

    .about-grid,
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .footer-section p {
        margin: 0 auto;
    }

    .values-list li:hover {
        transform: none;
    }
}

/* ========== Responsive ========== */
@media (max-width: 768px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-image {
        display: none;
    }

    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-cta {
        justify-content: center;
    }

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

    .nav-links {
        display: none;
    }

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

@media (max-width: 640px) {
    .hero-title {
        font-size: 2.5rem;
    }

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