html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
    font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
    background-color: #f5f5f5;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.header {
    background-color: #20b2aa;
    color: white;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.container {
    max-width: 1000px;
    margin: 30px auto;
    padding: 20px;
    flex: 1;
}

.card-container {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
}

.card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    padding: 30px;
    min-width: 280px;
    flex: 1 1 300px;
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.card h3 {
    margin-top: 0;
    color: #333;
    font-size: 1.5em;
}

.card p {
    color: #666;
    font-size: 1em;
    line-height: 1.5;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    background-color: #20b2aa;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    margin-top: 15px;
    transition: background-color 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn:hover {
    background-color: #18a09a;
    cursor: pointer;
}

.disabled-card {
    opacity: 0.6;
    background-color: #f8f8f8;
}

.disabled-btn {
    background-color: #ccc !important;
    cursor: not-allowed !important;
}

.disabled-btn:hover {
    background-color: #ccc !important;
}

.footer {
    text-align: center;
    padding: 20px;
    color: #999;
    font-size: 0.9em;
    background-color: #f8f8f8;
    margin-top: auto;
}