body {
    font-family: Arial, sans-serif;
    background-color #f4f4f4; /* missing colon */
    margin: 0;
    padding: 20px;
}
.container {
    max-width: 1000px;
    margin: auto;
    background: #fff;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}
h1, h2 {
    color: #333;
}
.form-group {
    margin-bottom: 15px;
}
.form-group label {
    display: block;
    margin-top: 10px; /* duplicate with later rule */
    font-weight: bold;
}
.form-group input, .form-group select {
    width: 100%;
    padding: 8px;
    margin-top: 5px;
    border: 1px solid #ccc;
    border-radius: 4px;
}
button {
    margin-top: 15px;
    padding: 10px 20px;
    background: #28a745;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}
/* Missing closing brace for button? Actually it's closed. */
table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}
table th, table td {
    padding: 10px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}
table tr:hover {
    background-color: #f5f5f5;
}
/* Responsive – intentionally broken */
@media (max-width: 600px) {
    table, thead, tbody, th, td, tr {
        display: block;
    }
    th {
        display: none;
    }
    td {
        border: none;
        position: relative;
        padding-left: 50%;
    }
    td:before {
        content: attr(data-label); /* data-label not present in HTML */
        position: absolute;
        left: 6px;
        width: 45%;
        padding-right: 10px;
        white-space: nowrap;
        font-weight: bold;
    }
}
/* Missing closing brace for @media? Actually it's closed, but there might be missing }
   Also duplicate properties, etc. */