:root {
    --primary: #1e6f4a;
    --primary-hover: #2a8c5e;
    --bg-hero: linear-gradient(135deg, #f0f8f4 0%, #e8f5e9 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.site-header {
    border-bottom: 1px solid var(--pico-muted-border-color);
    padding: 0.75rem 0;
    background: white;
    position: sticky;
    top: 0;
    z-index: 10;
}
.site-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.logo-emoji {
    font-size: 1.5rem;
}
.nav-actions {
    display: flex;
    gap: 1rem;
    align-items: center;
}
.nav-actions a {
    text-decoration: none;
    color: var(--pico-color);
}
.nav-actions .btn-login {
    background: var(--primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-weight: 500;
}

/* Hero */
.hero {
    background: var(--bg-hero);
    padding: 3rem 0 4rem;
    flex: 1;
}
.hero-grid {
    display: grid;
    grid-template-columns: 1fr 420px;
    gap: 3rem;
    align-items: center;
}
.hero-text .badge {
    display: inline-block;
    background: white;
    border: 1px solid var(--primary);
    color: var(--primary);
    padding: 0.25rem 0.75rem;
    border-radius: 99px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 1rem;
}
.hero-text h1 {
    font-size: 2.75rem;
    line-height: 1.15;
    margin-bottom: 1rem;
    color: #1a3a2a;
}
.hero-text p.lead {
    font-size: 1.1rem;
    color: #4a5a52;
    margin-bottom: 1.5rem;
    max-width: 540px;
}
.graph-illustration {
    margin-top: 2rem;
    max-width: 360px;
}

/* Login-Box */
.login-box {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 8px 24px rgba(0, 80, 40, 0.08);
    border: 1px solid #d8e8de;
}
.login-box h2 {
    font-size: 1.4rem;
    margin-bottom: 1.25rem;
    color: #1a3a2a;
}
.btn-google {
    width: 100%;
    background: white;
    color: #3c4043;
    border: 1px solid #dadce0;
    padding: 0.65rem 1rem;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    cursor: pointer;
    margin-bottom: 1rem;
}
.btn-google:hover {
    background: #f8f9fa;
}
.btn-google svg {
    width: 18px;
    height: 18px;
}
.divider {
    display: flex;
    align-items: center;
    text-align: center;
    color: var(--pico-muted-color);
    margin: 1rem 0;
    font-size: 0.85rem;
}
.divider::before, .divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--pico-muted-border-color);
}
.divider:not(:empty)::before { margin-right: 0.75rem; }
.divider:not(:empty)::after { margin-left: 0.75rem; }

.login-box input {
    margin-bottom: 0.75rem;
}
.btn-primary {
    width: 100%;
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.65rem;
    border-radius: 6px;
    font-weight: 500;
    cursor: pointer;
    font-size: 0.95rem;
}
.btn-primary:hover {
    background: var(--primary-hover);
}
.login-box .footer-links {
    text-align: center;
    margin-top: 1rem;
    font-size: 0.9rem;
    color: var(--pico-muted-color);
}
.login-box .footer-links a {
    color: var(--primary);
    text-decoration: none;
}

/* Footer */
.site-footer {
    border-top: 1px solid var(--pico-muted-border-color);
    padding: 1.25rem 0;
    font-size: 0.875rem;
    color: var(--pico-muted-color);
    background: white;
}
.site-footer .container {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}
.site-footer a {
    color: var(--pico-muted-color);
    text-decoration: none;
    margin: 0 0.5rem;
}
.site-footer a:hover {
    color: var(--primary);
}

/* Knowledge Graph SVG animation (subtle pulse) */
.graph-node {
    transform-origin: center;
    transform-box: fill-box;
    animation: pulse 4s ease-in-out infinite;
}
.graph-node:nth-child(odd) {
    animation-delay: 1s;
}
.graph-node:nth-child(3n) {
    animation-delay: 2s;
}
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.65; }
}

/* Responsive */
@media (max-width: 900px) {
    .hero-grid {
        grid-template-columns: 1fr;
    }
    .hero-text h1 {
        font-size: 2rem;
    }
    .graph-illustration {
        max-width: 280px;
    }
}