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

body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #dbeafe, #eff6ff);
    min-height: 100vh;
    padding: 40px 20px;
    color: #1e293b;
}

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

h1 {
    text-align: center;
    font-size: 42px;
    color: #0f172a;
    margin-bottom: 10px;
}

.subtitle {
    text-align: center;
    font-size: 18px;
    color: #64748b;
    margin-bottom: 40px;
}

.week11-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 25px;
}

.card {
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    color: white;
    text-decoration: none;
    border-radius: 22px;
    padding: 30px 20px;
    text-align: center;
    transition: 0.3s ease;
    box-shadow: 0 10px 20px rgba(37, 99, 235, 0.25);
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 30px rgba(37, 99, 235, 0.35);
}

.card h2 {
    font-size: 30px;
    margin-bottom: 12px;
}

.card p {
    color: #dbeafe;
    font-size: 15px;
    line-height: 1.5;
}

.footer {
    text-align: center;
    margin-top: 40px;
    color: #64748b;
    font-size: 15px;
}