/* CSS Custom Properties for Modern Dark Theme */
:root {
    --primary-bg: #0d1117;
    --secondary-bg: #161b22;
    --card-bg: #21262d;
    --accent-primary: #00d4ff;
    --accent-secondary: #7c3aed;
    --accent-success: #00c851;
    --accent-warning: #ff6b35;
    --text-primary: #f0f6fc;
    --text-secondary: #7d8590;
    --text-muted: #6e7681;
    --border-color: #30363d;
    --hover-bg: #30363d;
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #7c3aed 100%);
    --gradient-secondary: linear-gradient(135deg, #7c3aed 0%, #00c851 100%);
    --shadow-small: 0 2px 10px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 8px 30px rgba(0, 0, 0, 0.4);
    --shadow-large: 0 20px 60px rgba(0, 0, 0, 0.5);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius: 16px;
    --border-radius-small: 8px;
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    background: var(--primary-bg);
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(0, 212, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(124, 58, 237, 0.1) 0%, transparent 50%);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation Styles */
.header {
    background-color: var(--secondary-bg);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

.nav-brand h1 {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    position: relative;
}

.nav-brand h1::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient-primary);
    border-radius: 1px;
    opacity: 0.6;
}

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

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    font-weight: 500;
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--gradient-primary);
    transition: var(--transition);
    border-radius: 2px;
}

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

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--secondary-bg) 0%, var(--primary-bg) 100%);
    padding: 4rem 0;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 900;
    letter-spacing: -0.03em;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    background: var(--gradient-primary);
    color: white;
    padding: 16px 40px;
    text-decoration: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: var(--shadow-medium);
    position: relative;
    overflow: hidden;
}

.cta-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: var(--transition);
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-large);
}

.cta-button:hover::before {
    left: 100%;
}

/* Section Styles */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

.featured-articles,
.health-categories {
    padding: 4rem 0;
}

/* Article Grid */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.article-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow-small);
    transition: var(--transition);
    position: relative;
}

.article-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition);
}

.article-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-large);
    border-color: var(--accent-primary);
}

.article-card:hover::before {
    opacity: 1;
}

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

.article-content {
    padding: 1.5rem;
}

.article-title {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.article-excerpt {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.article-category {
    background: var(--gradient-primary);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

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

.read-more {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.read-more::after {
    content: '→';
    transition: var(--transition);
}

.read-more:hover {
    color: var(--accent-secondary);
}

.read-more:hover::after {
    transform: translateX(4px);
}

/* Categories Grid */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.category-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

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

.category-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.category-card p {
    color: var(--text-secondary);
}

/* Article Page Styles */
.article-header {
    background-color: var(--secondary-bg);
    padding: 3rem 0;
    text-align: center;
}

.article-main {
    max-width: 800px;
    margin: 0 auto;
    padding: 3rem 2rem;
}

.article-body {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.article-body h2 {
    color: var(--text-primary);
    margin: 2rem 0 1rem 0;
    font-size: 1.8rem;
}

.article-body h3 {
    color: var(--text-primary);
    margin: 1.5rem 0 1rem 0;
    font-size: 1.4rem;
}

.article-body p {
    margin-bottom: 1.5rem;
}

.article-body ul,
.article-body ol {
    margin-left: 2rem;
    margin-bottom: 1.5rem;
}

.article-body li {
    margin-bottom: 0.5rem;
}

/* Comments Section */
.comments-section {
    background-color: var(--secondary-bg);
    padding: 3rem 0;
}

.comments-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 2rem;
}

.comments-title {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--text-primary);
}

.comment {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--accent-green);
}

.comment-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.comment-author {
    font-weight: bold;
    color: var(--accent-green);
}

.comment-date {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.comment-body {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Form Styles */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: bold;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--card-bg);
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent-green);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-button {
    background-color: var(--accent-green);
    color: white;
    padding: 12px 30px;
    border: none;
    border-radius: 8px;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
}

.form-button:hover {
    background-color: #45a049;
}

/* About Page Styles */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 3rem 2rem;
}

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

.about-section h2 {
    color: var(--accent-green);
    margin-bottom: 1rem;
    font-size: 1.8rem;
}

.about-section p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 1rem;
}

/* Contact Page Styles */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    padding: 3rem 2rem;
}

.contact-info {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 3rem;
    box-shadow: var(--shadow);
}

.contact-info h3 {
    color: var(--accent-green);
    margin-bottom: 1rem;
}

.contact-info p {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Footer Styles */
.footer {
    background-color: var(--secondary-bg);
    padding: 3rem 0 1rem 0;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1rem;
    font-weight: 700;
}

.footer-section p {
    color: var(--text-secondary);
    line-height: 1.6;
}

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

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

.footer-section ul li a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
}

.footer-section ul li a:hover {
    color: var(--accent-primary);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        gap: 1rem;
    }

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

    .hero-subtitle {
        font-size: 1rem;
    }

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

    .section-title {
        font-size: 2rem;
    }

    .comment-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .nav {
        padding: 1rem;
    }

    .hero {
        padding: 2rem 0;
    }

    .featured-articles,
    .health-categories {
        padding: 2rem 0;
    }

    .article-main,
    .about-content,
    .contact-content {
        padding: 2rem 1rem;
    }
}