/* ==================== */
/* CSS Variables & Reset */
/* ==================== */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #10b981;
    --accent: #f59e0b;
    --dark: #0f172a;
    --dark-light: #1e293b;
    --gray: #64748b;
    --gray-light: #94a3b8;
    --light: #f1f5f9;
    --white: #ffffff;
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 12px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: var(--light);
    color: var(--dark);
    line-height: 1.6;
}

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

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

/* ==================== */
/* Header & Navigation */
/* ==================== */
.header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
}

.logo-icon {
    font-size: 1.8rem;
}

.logo .highlight {
    color: var(--primary);
}

.nav {
    display: flex;
    gap: 30px;
}

.nav-link {
    font-weight: 500;
    color: var(--gray);
    padding: 8px 0;
    border-bottom: 2px solid transparent;
}

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

/* ==================== */
/* Hero Section */
/* ==================== */
.hero {
    background: var(--gradient-1);
    color: var(--white);
    padding: 60px 20px;
    text-align: center;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.hero p {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* ==================== */
/* Ad Banner */
/* ==================== */
.ad-banner {
    margin: 30px auto;
    text-align: center;
}

.ad-placeholder {
    background: var(--dark-light);
    color: var(--gray-light);
    padding: 40px;
    border-radius: var(--radius);
    font-size: 0.9rem;
}

/* ==================== */
/* Main Content */
/* ==================== */
.main {
    padding: 40px 20px;
}

.section-title {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: var(--dark);
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
}

/* ==================== */
/* Article Cards */
/* ==================== */
.article-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.article-image {
    height: 180px;
    display: flex;
    align-items: flex-start;
    justify-content: flex-end;
    padding: 15px;
}

.category {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    color: var(--white);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.article-content {
    padding: 20px;
}

.article-content h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    line-height: 1.4;
}

.article-content h3 a:hover {
    color: var(--primary);
}

.article-content p {
    color: var(--gray);
    font-size: 0.95rem;
    margin-bottom: 15px;
}

.article-meta {
    display: flex;
    gap: 20px;
    font-size: 0.85rem;
    color: var(--gray-light);
}

/* ==================== */
/* Footer */
/* ==================== */
.footer {
    background: var(--dark);
    color: var(--gray-light);
    padding: 50px 20px 20px;
    margin-top: 50px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: var(--white);
    font-size: 1.1rem;
    margin-bottom: 20px;
}

.footer-section p {
    font-size: 0.9rem;
    line-height: 1.7;
}

.footer-section a {
    display: block;
    color: var(--gray-light);
    padding: 5px 0;
    font-size: 0.9rem;
}

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

.footer-bottom {
    border-top: 1px solid var(--dark-light);
    padding-top: 20px;
    text-align: center;
    font-size: 0.85rem;
}

/* ==================== */
/* Post Page Styles */
/* ==================== */
.post-header {
    background: var(--gradient-1);
    color: var(--white);
    padding: 50px 20px;
}

.post-header .category {
    margin-bottom: 15px;
    display: inline-block;
}

.post-header h1 {
    font-size: 2rem;
    line-height: 1.3;
    max-width: 800px;
}

.post-meta {
    margin-top: 15px;
    opacity: 0.9;
}

.post-content {
    background: var(--white);
    max-width: 900px;
    margin: -30px auto 40px;
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
}

.post-content h2 {
    color: var(--dark);
    font-size: 1.5rem;
    margin: 30px 0 15px;
    padding-top: 20px;
    border-top: 1px solid var(--light);
}

.post-content h3 {
    color: var(--dark);
    font-size: 1.2rem;
    margin: 25px 0 10px;
}

.post-content p {
    margin-bottom: 15px;
    color: var(--dark);
}

.post-content ul, .post-content ol {
    margin: 15px 0;
    padding-left: 25px;
}

.post-content li {
    margin-bottom: 8px;
}

.post-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.post-content th, .post-content td {
    padding: 12px 15px;
    border: 1px solid var(--light);
    text-align: left;
}

.post-content th {
    background: var(--dark);
    color: var(--white);
}

.post-content tr:nth-child(even) {
    background: var(--light);
}

/* Download Button */
.download-btn {
    display: inline-block;
    background: var(--gradient-2);
    color: var(--white);
    padding: 12px 30px;
    border-radius: 25px;
    font-weight: 600;
    margin: 10px 0;
    transition: var(--transition);
}

.download-btn:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

/* ==================== */
/* Page Styles */
/* ==================== */
.page-header {
    background: var(--dark);
    color: var(--white);
    padding: 50px 20px;
    text-align: center;
}

.page-header h1 {
    font-size: 2rem;
}

.page-content {
    background: var(--white);
    max-width: 800px;
    margin: 40px auto;
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.page-content h2 {
    margin: 25px 0 15px;
    color: var(--dark);
}

.page-content p {
    margin-bottom: 15px;
}

.page-content ul {
    margin: 15px 0;
    padding-left: 25px;
}

/* ==================== */
/* Responsive */
/* ==================== */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 15px;
    }
    
    .nav {
        gap: 20px;
    }
    
    .hero h1 {
        font-size: 1.8rem;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .post-content {
        margin: -20px 10px 40px;
        padding: 20px;
    }
}