body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    background-color: aquamarine;
}


.table {
    width: 100%;
    text-align: center;
}


.nav-bar {
    background-color: black;
    padding: 10px 0;
    border-bottom: 4px solid rgb(0, 0, 0);
}

.nav-bar ul {
    padding: 0;
    margin: 0;
}

.nav-bar li {
    display: inline-block;
    margin: 0 20px;
}

.nav-bar a {
    text-decoration: none;
    color: white;
    font-weight: bold;
    font-size: 18px;
}

.nav-bar a:hover {
    text-decoration: underline;
}

.Grades h1 {
    margin-top: 20px;
    font-size: 40px;
    color: black;
    border: 2px solid black;
    display: inline-block;
    padding: 8px 20px;
    border-radius: 10px;
    background: rgba(255,255,255,0.3);
}


.Report {
    width: 90%;
    max-width: 900px;
    margin: 30px auto;
}

table {
    width: 100%;
    background: white;
    border-radius: 10px;
   
}

caption {
    font-size: 22px;
    padding: 10px;
    font-weight: bold;
}

th, td {
    border: 2px solid black;
    padding: 12px;
    text-align: center;
}

th {
    background-color: #ffe4b5;
    font-size: 18px;
}

tbody tr:nth-child(even) {
    background-color: #f8f8f8;
}

tbody tr:hover {
    background-color: #d9ffd6;
    
}

footer {
    background-color: #F9B487;
    color: black;
    text-align: center;
    padding: 12px;
    font-size: 18px;
    border-top: 2px solid black;
    margin-top: 30px;
}

@media (max-width: 768px) {
    .nav-bar li {
        display: block;
        margin: 10px 0;
    }

    .Grades h1 {
        font-size: 28px;
        padding: 6px 14px;
    }

    table, th, td {
        font-size: 16px;
    }
}

@media (max-width: 500px) {
    table {
        font-size: 14px;
    }

    .nav-bar a {
        font-size: 16px;
    }

    th, td {
        padding: 8px;
    }

    caption {
        font-size: 18px;
    }
}