/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

/* Header */
header {
    background-color: #f8f9fa;
    border-bottom: 1px solid #e9ecef;
    padding: 1rem 0;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    gap: 2rem;
}

nav a {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    padding: 0.5rem 0;
    transition: color 0.2s ease;
}

nav a:hover,
nav a.active {
    color: #007bff;
}

/* Main content */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

h1 {
    margin-bottom: 2rem;
    color: #333;
    font-size: 2rem;
    font-weight: 600;
}

/* Data table */
table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
    background-color: #fff;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    border-radius: 8px;
    overflow: hidden;
}

th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #e9ecef;
}

th {
    background-color: #f8f9fa;
    font-weight: 600;
    color: #495057;
}

th.sortable {
    cursor: pointer;
    user-select: none;
    transition: background-color 0.2s ease;
    position: relative;
}

th.sortable:hover {
    background-color: #e9ecef;
}

th.sortable:active {
    background-color: #dee2e6;
}

tr:hover {
    background-color: #f8f9fa;
}

/* Loading state */
#data-container {
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Responsive */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    main {
        padding: 1rem;
    }
    
    h1 {
        font-size: 1.5rem;
    }
    
    table {
        font-size: 0.875rem;
    }
    
    th, td {
        padding: 0.5rem;
    }
}