html {
    background: #006eff;
}

body {
    background: black;
    color: #00ffc7;
    width: 900px;
    margin: 50px auto;
    padding: 30px;
    border: 3px solid #00ffc7;
    border-radius: 20px;
}

h1,
h2,
h3 {
    color: #0ecea4;
    text-align: center;
}

h1 {
    font-size: 40pt;
}

h2 {
    font-size: 25pt;
}

nav a {
    display: block;
    width: 130px;
}
nav a {
   
    margin: 10px 0 0 0;
    padding: 5px;
    color: #003311;
    background-color: white;
    border: 3px solid #003311;
   
}
nav a {
    
    font-size: 16pt;
    font-weight: bold;
    text-decoration: none;
   
}
nav a {
    
    text-align: center;    
    border-radius: 10px;
    box-shadow: 2px 4px 6px #333333;
 
}
nav a:hover {
    color: white;
    background-color: rgb(0, 236, 225);
}


img,
iframe {
    display: block;
    margin: 30px auto;
    border: 2px solid #00ffc7;
    border-radius: 15px;
}

ul,
ol {
    display: block;
    margin: 10px auto;
    width: 200px;
}

footer {
    color: #00ffc7;
}

p {
    text-align: center;
}

a {
    color: #04ebf3;
    text-decoration: none;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
}

.left-button,
.right-button {
    width: 130px;
    padding: 5px;
    color: #003311;
    background-color: white;
    border: 3px solid #00ffd5;
    font-size: 16pt;
    font-weight: bold;
    text-decoration: none;
    text-align: center;
    border-radius: 10px;
    box-shadow: 2px 4px 6px #333333;
}

.left-button:hover,
.right-button:hover {
    color: white;
    background-color: rgb(0, 236, 225);
}

.middle-button {
    display: inline-block;
    margin: 30px auto;
    padding: 10px 20px;
    font-size: 16pt;
    font-weight: bold;
    color: #003311;
    background-color: white;
    border: 3px solid #00ccff;
    text-decoration: none;
    text-align: center;
    border-radius: 10px;
    box-shadow: 2px 4px 6px #333333;
}

/* Center the nav container */
nav {
    text-align: center;
}


.center-nav {
    text-align: center;
    margin-top: 30px;
}

.center-button {
    display: inline-block;
    padding: 10px 20px;
    font-size: 16pt;
    font-weight: bold;
    color: #003311;
    background-color: white;
    border: 3px solid #00ccff;
    text-decoration: none;
    text-align: center;
    border-radius: 10px;
    box-shadow: 2px 4px 6px #333333;
}