/* Modern Clean Theme - AI Site Farm */
:root {
    --color-bg: #ffffff;
    --color-surface: #f8f9fa;
    --color-text: #1a1a2e;
    --color-text-secondary: #555;
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-border: #e5e7eb;
    --color-accent: #f59e0b;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --max-width: 1100px;
    --radius: 8px;
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 6rem;
}

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

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--color-primary); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--color-primary-hover); }
img { max-width: 100%; height: auto; }

/* Header / Navigation */
.site-header {
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg);
    position: sticky;
    top: 0;
    z-index: 100;
}
.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-sm) var(--space-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.site-logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
}
.nav-links { display: flex; gap: var(--space-md); }
.nav-links a { color: var(--color-text-secondary); font-weight: 500; }
.nav-links a:hover { color: var(--color-primary); }

/* Hero */
.hero {
    padding: var(--space-xl) var(--space-md);
    background: linear-gradient(135deg, #f0f4ff 0%, #e8ecff 100%);
}
.hero-content {
    max-width: var(--max-width);
    margin: 0 auto;
}
.hero-title {
    font-size: clamp(2rem, 4vw, 3.5rem);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--space-sm);
    color: var(--color-text);
}
.hero-intro {
    font-size: 1.15rem;
    color: var(--color-text-secondary);
    max-width: 700px;
    line-height: 1.7;
}

/* Sections */
.section-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--space-lg) var(--space-md);
}
.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--space-md);
    color: var(--color-text);
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-md);
}
.feature-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: var(--space-md);
    transition: transform 0.2s, box-shadow 0.2s;
}
.feature-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.feature-card h3 { font-size: 1.1rem; margin-bottom: var(--space-xs); }

/* Articles Grid */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--space-md);
}
.article-card {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: var(--space-md);
    transition: transform 0.2s, box-shadow 0.2s;
}
.article-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.06);
}
.article-card h3 { font-size: 1.15rem; margin-bottom: var(--space-xs); }
.article-card h3 a { color: var(--color-text); }
.article-card h3 a:hover { color: var(--color-primary); }
.article-excerpt { color: var(--color-text-secondary); font-size: 0.95rem; margin-bottom: var(--space-sm); }
.article-meta { display: flex; gap: var(--space-sm); font-size: 0.85rem; color: #888; }

/* About Section */
.about-section {
    background: var(--color-surface);
}
.about-section p {
    max-width: 700px;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* Article Page */
.article-page { padding: var(--space-lg) var(--space-md); }
.article-container { max-width: 720px; margin: 0 auto; }
.article-header { margin-bottom: var(--space-lg); }
.article-header h1 { font-size: 2rem; line-height: 1.3; margin-bottom: var(--space-sm); }
.article-content { font-size: 1.05rem; line-height: 1.8; }
.article-content h2 { font-size: 1.5rem; margin-top: var(--space-lg); margin-bottom: var(--space-sm); }
.article-content h3 { font-size: 1.2rem; margin-top: var(--space-md); margin-bottom: var(--space-xs); }
.article-content p { margin-bottom: var(--space-sm); }
.article-content ul, .article-content ol { margin-bottom: var(--space-sm); padding-left: var(--space-md); }
.article-content li { margin-bottom: 0.25rem; }
.article-nav { margin-top: var(--space-lg); padding-top: var(--space-md); border-top: 1px solid var(--color-border); }

/* Page */
.page-content { padding: var(--space-lg) var(--space-md); }
.page-container { max-width: 720px; margin: 0 auto; }
.page-body { line-height: 1.8; }
.page-body p { margin-bottom: var(--space-sm); }

/* Footer */
.site-footer {
    border-top: 1px solid var(--color-border);
    padding: var(--space-md);
    margin-top: var(--space-lg);
}
.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--space-sm);
}
.footer-links { display: flex; gap: var(--space-md); }
.footer-links a { color: var(--color-text-secondary); font-size: 0.9rem; }
.footer-copy { color: #999; font-size: 0.85rem; }

/* Responsive */
@media (max-width: 640px) {
    .nav-container { flex-direction: column; gap: var(--space-xs); }
    .hero { padding: var(--space-lg) var(--space-sm); }
    .features-grid, .articles-grid { grid-template-columns: 1fr; }
    .footer-container { flex-direction: column; text-align: center; }
}