body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f4f6f9;
}

h1 {
    color: #2c3e50;
    text-align: center;
    border-bottom: 3px solid #3498db;
    padding-bottom: 10px;
    margin-bottom: 20px;
}

h3 {
    color: #2980b9;
    margin-top: 25px;
    border-left: 4px solid #3498db;
    padding-left: 10px;
}

p {
    text-align: justify;
    margin-bottom: 15px;
}

list {
    display: block;
    margin-left: 30px;
}

list li {
    margin-bottom: 10px;
    position: relative;
    padding-left: 20px;
}

list li::before {
    content: '•';
    color: #3498db;
    font-weight: bold;
    position: absolute;
    left: -20px;
}

.alert {
    background-color: #d4edda;
    color: #155724;
    padding: 15px;
    margin: 10px 0;
    border-radius: 4px;
    border: 1px solid #c3e6cb;
    animation: fadeOut 5s forwards;
}

@keyframes fadeOut {
    0% { opacity: 1; }
    90% { opacity: 1; }
    100% { opacity: 0; }
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }
    
    h1 {
        font-size: 24px;
    }
    
    h3 {
        font-size: 20px;
    }
}