@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

:root {
    --bg: #ffffff;
    --bg-subtle: #f8fafc;
    --border: #e2e8f0;
    --text: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --card-shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --card-shadow-hover: 0 10px 25px rgba(0,0,0,0.08);
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* ---------- Navbar ---------- */
.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 48px;
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.logo {
    height: 36px;
}

.logo-text {
    font-size: 1.15rem;
    font-weight: 800;
    color: var(--text);
    letter-spacing: -0.5px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 4px;
}

.nav-links li a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.88rem;
    padding: 7px 16px;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.nav-links li a:hover,
.nav-links li a.active {
    color: var(--text);
    background: var(--bg-subtle);
}

/* ---------- Hero ---------- */
.hero {
    max-width: 680px;
    margin: 0 auto;
    text-align: center;
    padding: 100px 24px 72px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px 14px;
    border-radius: 50px;
    background: #eff6ff;
    color: var(--accent);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 20px;
}

.hero-badge .dot {
    width: 6px;
    height: 6px;
    background: #22c55e;
    border-radius: 50%;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 900;
    line-height: 1.1;
    letter-spacing: -1.5px;
    color: var(--text);
    margin-bottom: 16px;
}

.hero h1 .gradient-text {
    background: linear-gradient(135deg, #2563eb, #7c3aed);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto 32px;
}

.hero-stats {
    display: flex;
    gap: 40px;
    justify-content: center;
    padding-top: 32px;
    border-top: 1px solid var(--border);
    margin-top: 32px;
}

.stat-number {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text);
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 2px;
}

/* ---------- Challenges ---------- */
.blog-container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 24px 80px;
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-header h2 {
    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.section-header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-top: 6px;
}

.blog-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 20px;
}

.blog-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    transition: box-shadow 0.3s ease, transform 0.3s ease;
    box-shadow: var(--card-shadow);
}

.blog-card:hover {
    box-shadow: var(--card-shadow-hover);
    transform: translateY(-3px);
}

.card-image-wrapper {
    overflow: hidden;
}

.card-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
    display: block;
    transition: transform 0.4s ease;
}

.blog-card:hover .card-image {
    transform: scale(1.03);
}

.card-body {
    padding: 20px;
}

.card-tag {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 5px;
    font-size: 0.68rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 10px;
}

.tag-web { background: #fef2f2; color: #dc2626; }
.tag-osint { background: #f0fdf4; color: #16a34a; }

.card-body h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 6px;
    letter-spacing: -0.3px;
}

.card-body p {
    font-size: 0.87rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 20px;
    border-top: 1px solid var(--border);
}

.difficulty {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.78rem;
    color: var(--text-muted);
}

.difficulty-dots {
    display: flex;
    gap: 3px;
}

.difficulty-dots .dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: #e2e8f0;
}

.difficulty-dots .dot.filled {
    background: var(--accent);
}

.points {
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--accent);
}

/* ---------- Footer ---------- */
footer {
    text-align: center;
    padding: 32px 20px;
    border-top: 1px solid var(--border);
}

footer .footer-links {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-bottom: 12px;
}

footer .footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.82rem;
    transition: color 0.2s;
}

footer .footer-links a:hover { color: var(--text); }

footer p {
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
    .navbar { padding: 12px 20px; }
    .nav-links { display: none; }
    .hero { padding: 72px 20px 56px; }
    .hero h1 { font-size: 2.2rem; }
    .hero-stats { gap: 24px; }
    .blog-list { grid-template-columns: 1fr; }
}