:root {
    /* Color Palette */
    --bg-color: #f8fafc;
    --surface-color: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --accent-color: #4f46e5;      /* Indigo */
    --accent-hover: #4338ca;
    --border-color: #e2e8f0;
    
    /* Typography */
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    
    /* Effects */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --transition: all 0.2s ease-in-out;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- Header --- */
.site-header {
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-main);
    letter-spacing: -0.5px;
}

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

.nav-links {
    list-style: none;
    display: flex;
    gap: 32px;
}

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

.nav-links a:hover, .nav-links a.active {
    color: var(--accent-color);
}

/* --- Hero Section --- */
.hero {
    padding: 80px 0 60px;
    text-align: center;
    background: linear-gradient(180deg, #ffffff 0%, var(--bg-color) 100%);
    border-bottom: 1px solid var(--border-color);
}

.hero-badge {
    display: inline-block;
    background-color: #e0e7ff;
    color: var(--accent-color);
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.hero h2 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 16px;
    color: #0f172a;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.2;
}

.hero p {
    font-size: 1.15rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

/* --- Main Content & Filters --- */
.main-content {
    padding: 60px 24px;
}

.filter-bar {
    display: flex;
    gap: 12px;
    margin-bottom: 40px;
    flex-wrap: wrap;
    justify-content: center;
}

.filter-btn {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    font-family: inherit;
    transition: var(--transition);
}

.filter-btn:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.filter-btn.active {
    background-color: var(--accent-color);
    color: #ffffff;
    border-color: var(--accent-color);
}

/* --- Blog Cards Feed --- */
.grid-feed {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 32px;
}

.card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: #cbd5e1;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    font-size: 0.85rem;
}

.card-category {
    color: var(--accent-color);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.card-read-time {
    color: var(--text-muted);
}

.card-title {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 12px;
    line-height: 1.3;
}

.card-title a:hover {
    color: var(--accent-color);
}

.card-excerpt {
    font-size: 1rem;
    color: var(--text-muted);
    flex-grow: 1;
    margin-bottom: 24px;
}

.card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border-color);
    padding-top: 16px;
    font-size: 0.9rem;
}

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

.card-link {
    color: var(--accent-color);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
}

.card-link:hover {
    color: var(--accent-hover);
    gap: 10px; /* Slight animation effect */
}

/* --- Footer --- */
.site-footer {
    background-color: #0f172a;
    color: #f8fafc;
    margin-top: 80px;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    margin-bottom: 40px;
}

.footer-brand p {
    color: #94a3b8;
    margin: 16px auto;
    max-width: 400px;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 16px;
}

.social-links a {
    color: #f8fafc;
    background-color: #1e293b;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-size: 1.1rem;
}

.social-links a:hover {
    background-color: var(--accent-color);
    transform: translateY(-2px);
}

.footer-bottom {
    background-color: #020617;
    padding: 20px 0;
    text-align: center;
    color: #64748b;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h2 { font-size: 2.2rem; }
    .footer-grid { grid-template-columns: 1fr; }
    .nav-links { display: none; /* Add hamburger menu logic later if needed */ }
}