body {
    margin: 0px;
    padding: 0px;
    font-family: Arial, sans-serif;
}

header {
    display: block;
    height: 50px;
    background-color: aliceblue;
    padding: 20px;
    text-align: center;
}

p {
    color: blue;
}
#main_container {
    display: flex;
    justify-content: center; 
    align-items: center;    
    /*height: 100vh;       */
}
#div_c {
    width: 900px;           
    height: 600px;          
    background-color: #4CAF50; 
    color: white;           
    display: flex;          
    justify-content: center; 
    align-items: center;    
    border-radius: 10px;    
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2); 
}

/* Mobil */
@media (max-width: 768px) {
    
}