body {
    margin: 0;
    padding: 0;
    background-color: #000000;  
    font-family: Nirmala UI, Helvetica, Arial, sans-serif;
    font-size: 14px; /* Check font-size */
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
}
   
header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #002828; /* Before 01cc87 */
    padding: 5px; /* Before 10px */
    text-align: center;
    border-bottom: 1px solid #01cc87;
}
  
header img {
    max-width: 100%;
    height: auto; 
}

main nav {
    margin-top: 175px; 
    text-align: center;
}
  
main nav a {
    text-decoration: none;
    font-size: 16px;
    color: #DBDBDB;      
    background-color: #000000;
    border: 2px solid #01cc87;
    padding: 10px 50px;
    border-radius: 20px;      
    display: block;
}
  
main nav a:hover {
    color: #fff;
    box-shadow: 0 4px 16px #01cc87;
    transition: all 0.2s ease;
}
  
main {
    margin: 20px 15%;
}

footer {
    /* margin-top: auto; */
    position: fixed;
    bottom: 0;
    text-align: center;
    font-size: 14px; /**/
    background-color: #002828;
    width: 100%;
    padding-top: 10px; /**/
    padding-bottom: 10px; /**/
    border-top: 1px solid #01cc87;
}
  
footer a {
    text-decoration: none;
    color: #DBDBDB;
}