body {
    font-family: 'Courier New', Courier, monospace;
    background-color: #1e1e1e; 
    color: #33ff33; 
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh; 
}

header {
    background-color: #333; 
    color: #33ff33; 
    padding: 20px 0;
    text-align: center;
}

nav {
    display: flex;
    justify-content: space-around;
    background-color: #252525; 
    padding: 10px 0;
}

nav a {
    color: #33ff33;
    text-decoration: none; 
    padding: 10px;
    border-radius: 5px;
    transition: background-color 0.3s;
}

nav a:hover {
    background-color: #1e1e1e; 
    border: 1px solid #33ff33; 
}

main {
    flex-grow: 1;
    width: 80%; 
    max-width: 1200px;
    margin: 20px auto;
    padding: 20px;
    background-color: #252525; 
    box-shadow: 0 0 10px #33ff33; 
    border: 1px solid #33ff33; 
    overflow: auto; 
}

article {
    padding: 20px;
    margin-bottom: 20px; 
}

h1, h2, h3 {
    color: #50fa7b; 
}

p {
    margin-bottom: 15px;
    line-height: 1.6;
}

strong {
    color: #bd93f9;
}

footer {
    text-align: center;
    padding: 10px 0;
    background-color: #333; 
    color: #33ff33; 
    width: 100%; 
    margin-top: auto;
}

.video-tutorials {
    margin: 20px auto;
    padding: 20px;
}

.video-wrapper {
    margin-bottom: 20px; 
}

.video-wrapper h3 {
    color: #50fa7b;
    margin-bottom: 10px;
}

.video-tutorials iframe {
    width: 100%; 
    height: 315px; 
    max-width: 560px;
    margin: auto;
}

@media (max-width: 560px) {
    .video-tutorials iframe {
        height: auto; 
        width: 100%; 
    }
}

.back-to-cryptography {
    text-align: left;
    padding: 10px 20px; 
}

.back-to-cryptography a {
    color: #33ff33;
    text-decoration: none; 
    display: inline-block;
    padding: 5px 10px;
    background-color: #252525;
    border-radius: 5px; 
    margin-bottom: 20px;
}

.back-to-cryptography a:hover {
    color: #ffffff;
    background-color: #1e1e1e;
}