:root {
    --primary-color: #004caf;
    --secondary-color: #60a5fa;
    /* Blue Accent */
    --primary-hover: #003a8c;
    --bg-color: #f8fafc;
    --text-color: #1e293b;
    --text-muted: #64748b;
    --card-bg: #ffffff;
    --card-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --card-shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --container-width: 1100px;
}

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

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

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 2rem;
}

/* Main Content */
.main-content {
    padding: 2rem 0;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.intro {
    text-align: center;
    margin-bottom: 4rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.intro h2 {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.intro p {
    font-size: 1rem;
    color: var(--text-muted);
}

/* Grid Layout */
.nav-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.nav-card {
    background: var(--card-bg);
    border-radius: 1rem;
    padding: 2rem;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: var(--card-shadow);
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 2.5rem;
    border: 1px solid #f1f5f9;
}

.nav-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--card-shadow-hover);
    border-color: var(--primary-color);
}

.visual-container {
    width: 160px;
    flex-shrink: 0;
    display: flex;
    justify-content: center;
    align-items: center;
}

.card-logo {
    max-width: 130px;
    max-height: 160px;
    width: auto;
    height: auto;
    display: block;
    transition: transform 0.3s ease;
}

.nav-card:hover .card-logo {
    transform: scale(1.1);
}

.nav-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.nav-card p {
    font-size: 1rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: #f1f5f9;
    color: var(--primary-color);
    font-weight: 600;
    border-radius: 0.5rem;
    transition: all 0.2s ease;
}

.nav-card:hover .btn {
    background-color: var(--primary-color);
    color: #ffffff;
}

/* Responsiveness */
@media (max-width: 768px) {
    .container {
        padding: 0 1.5rem;
    }

    .intro h2 {
        font-size: 1.75rem;
    }

    .nav-card {
        flex-direction: column;
        align-items: flex-start;
        padding: 2rem;
        gap: 1.5rem;
    }

    .visual-container {
        width: 100%;
        margin-bottom: 1rem;
    }

    .card-logo {
        max-width: 180px;
        max-height: 100px;
    }
}