body {
    font-family: 'Roboto', sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    color: #333;
    background-color: #f4f4f4;
}

header {
    background-color: #333;
    color: white;
    padding: 1rem 0;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 1rem;
}

.logo {
    font-size: 1.5em;
    font-weight: bold;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1rem;
    margin: 0;
    padding: 0;
}

.nav-links li {
    margin: 0;
}

.nav-links a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #4CAF50;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5em;
    color: white;
    cursor: pointer;
}

main {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

section {
    margin-bottom: 2rem;
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

.history-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.history-item {
    background-color: #f7f7f7;
    padding: 1rem;
    border-left: 4px solid #4CAF50;
}

.positivity {
    background-color: #e8f5e9;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
    text-align: center;
}

footer {
    background-color: #333;
    color: white;
    text-align: center;
    padding: 1rem 0;
}

.back-to-top {
    display: none;
    position: fixed;
    bottom: 30px;
    right: 30px;
    padding: 0.5rem 1rem;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    transition: background-color 0.3s;
}

.back-to-top:hover {
    background-color: #45a049;
}

@media (max-width: 768px) {
    .nav-links {
        flex-direction: column;
        display: none;
    }

    .nav-links.nav-active {
        display: flex;
    }

    .nav-toggle {
        display: block;
    }
}