body {
    font-family: Arial, sans-serif;
    margin: 0;
    background-color: #f9f9f9;
    color: #333;
    transition: background-color 0.3s, color 0.3s;
}

.header {
    background-color: #3f51b5;
    color: white;
    padding: 20px;
    text-align: center;
}

.header button {
    background: none;
    border: 2px solid white;
    color: white;
    padding: 10px 20px;
    cursor: pointer;
    margin-top: 10px;
    border-radius: 5px;
}

.header button:hover {
    background-color: white;
    color: #3f51b5;
}

.content {
    padding: 20px;
}

.applications {
    max-width: 1200px;
    margin: 0 auto;
}

.applications h2 {
    color: #3f51b5;
}

.router-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

.router {
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    padding: 20px;
    margin: 10px;
    flex: 1 1 calc(33.333% - 20px);
    max-width: calc(33.333% - 20px);
    text-align: center;
    cursor: pointer;
    transition: box-shadow 0.3s ease;
    box-sizing: border-box;
}

.router:hover {
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.router h2 {
    margin: 0;
    color: #3f51b5;
    text-transform: uppercase;
}

.router p {
    margin: 10px 0 0;
    color: #666;
}

/* Dark Mode */
.dark-mode {
    background-color: #121212;
    color: #e0e0e0;
}

.dark-mode .header {
    background-color: #1e1e1e;
}

.dark-mode .header button {
    border-color: #e0e0e0;
}

.dark-mode .header button:hover {
    background-color: #e0e0e0;
    color: #1e1e1e;
}

.dark-mode .applications h2 {
    color: #bb86fc;
}

.dark-mode .router {
    background-color: #1e1e1e;
    color: #e0e0e0;
}

.dark-mode .router h2 {
    color: #bb86fc;
}

.dark-mode .router:hover {
    box-shadow: 0 4px 8px rgba(255, 255, 255, 0.2);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .router {
        flex: 1 1 calc(50% - 20px);
        max-width: calc(50% - 20px);
    }
}

@media (max-width: 768px) {
    .router {
        flex: 1 1 calc(50% - 20px);
        max-width: calc(50% - 20px);
    }
}

@media (max-width: 480px) {
    .router {
        flex: 1 1 100%;
        max-width: 100%;
    }
}