* {
    box-sizing: border-box;
}

body, html {
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    height: 100%;
}

body {
    display: flex;
    flex-direction: column;
}

header {
    background-color: #000000;
    color: white;
    padding: 15px 20px;
    width: 100%;
    position: sticky;
    top: 0;
    z-index: 1001;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

header nav ul {
    list-style: none;
    padding: 0;
    margin: 0 0 10px 0;
    display: flex;
    flex-wrap: wrap;
    gap: 0;
}

header nav ul li {
    padding: 10px 15px;
    white-space: normal;
    border-right: 1px solid #333;
    transition: background-color 0.3s;
}

header nav ul li:last-child {
    border-right: none;
}

header nav ul li a {
    text-decoration: none;
    color: inherit;
    display: block;
    font-weight: 500;
}

header nav li:hover {
    background-color: #f5f5f5;
    color: #000000;
}

header form {
    margin-top: 0;
    display: flex;
    gap: 8px;
    align-items: center;
    flex-wrap: wrap;
}

header form input {
    padding: 8px 12px;
    border: none;
    border-radius: 4px;
    width: 300px;
    font-size: 14px;
}

header form button {
    padding: 8px 16px;
    background-color: #6c757d;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}

header form button:hover {
    background-color: #5a6268;
}

.page-container {
    display: flex;
    flex: 1;
    min-height: calc(100vh - 80px);
}

aside {
    width: 22%;
    min-height: 100%;
    background-color: #e8e8e8;
    padding: 20px;
    box-sizing: border-box;
    overflow-y: auto;
    box-shadow: 2px 0 4px rgba(0,0,0,0.1);
    flex-shrink: 0;
}

aside h3 {
    margin-top: 0;
    margin-bottom: 15px;
    color: #000000;
    font-size: 18px;
    border-bottom: 2px solid #999;
    padding-bottom: 10px;
}

aside label {
    display: block;
    padding: 8px 10px;
    margin: 2px 0;
    border-bottom: 1px solid #ccc;
    cursor: pointer;
    border-radius: 3px;
    transition: background-color 0.2s;
    font-size: 14px;
}

aside label:hover {
    background-color: #d0d0d0;
}

aside label input[type="checkbox"] {
    margin-right: 8px;
    cursor: pointer;
}

aside button {
    margin-top: 10px;
    padding: 8px 12px;
    background-color: #6c757d;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    width: 100%;
}

aside button:hover {
    background-color: #5a6268;
}

main {
    flex: 1;
    padding: 20px;
    box-sizing: border-box;
    background-color: white;
    overflow-y: auto;
}

.info-section {
    text-align: center;
    padding: 15px 20px;
    background-color: #e8e8e8;
    border-bottom: 1px solid #999;
    font-size: 16px;
    font-weight: bold;
    margin: 0 0 20px 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    background-color: white;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    border-radius: 0;
    overflow: hidden;
    margin-top: 10px;
}

th, td {
    border: 1px solid #ddd;
    padding: 14px;
    text-align: left;
}

th {
    background-color: #333;
    font-weight: 600;
    color: white;
    text-transform: uppercase;
    font-size: 14px;
}

table tbody tr:hover {
    background-color: #f0f8ff;
}

table a {
    color: inherit;
}

table a:hover {
    color: #000000;
    font-weight: bold;
}

.category-column {
    width: 250px;
}

.description-column {
    display: none;
}

/* Responsive design */

/* Small mobile devices */
@media (max-width: 480px) {
    header {
        padding: 10px 12px;
    }
    header nav ul {
        flex-wrap: wrap;
        margin-bottom: 8px;
    }
    header nav ul li {
        padding: 6px 8px;
        font-size: 13px;
        border-right: 1px solid #333;
    }
    header form {
        flex-direction: column;
        gap: 6px;
    }
    header form input {
        width: 100%;
        font-size: 14px;
    }
    header form button {
        width: 100%;
        padding: 10px 12px;
    }
    .page-container {
        flex-direction: column;
        min-height: auto;
    }
    aside {
        width: 100%;
        min-height: auto;
        padding: 15px;
        box-shadow: none;
        border-top: 1px solid #ccc;
    }
    main {
        width: 100%;
        padding: 15px;
    }
    table {
        font-size: 13px;
    }
    th, td {
        padding: 10px;
    }
    .category-column {
        width: 120px;
    }
}

/* Mobile and tablet devices */
@media (max-width: 768px) and (min-width: 481px) {
    header {
        padding: 12px 15px;
    }
    header nav ul li {
        padding: 8px 10px;
        font-size: 14px;
    }
    header form input {
        width: 200px;
        font-size: 14px;
    }
    .page-container {
        flex-direction: column;
    }
    aside {
        width: 100%;
        min-height: auto;
        padding: 15px;
        border-top: 1px solid #ccc;
    }
    main {
        width: 100%;
    }
    table {
        font-size: 14px;
    }
}

/* Tablet devices */
@media (max-width: 1024px) and (min-width: 769px) {
    header form input {
        width: 250px;
    }
    aside {
        width: 25%;
    }
    th, td {
        padding: 12px;
    }
}

/* Large screens */
@media (min-width: 1025px) {
    header form input {
        width: 350px;
    }
    aside {
        width: 20%;
    }
    table {
        font-size: 15px;
    }
}