* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

nav {
    background: #1a237e;
    color: white;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

nav h1 {
    font-size: 1.3rem;
    font-weight: 600;
}

.nav-links a {
    color: #bbdefb;
    text-decoration: none;
    margin-left: 1.5rem;
    font-size: 0.9rem;
}

.nav-links a:hover {
    color: white;
}

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

.filters {
    background: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 1.5rem;
}

.filters form {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.filters label {
    font-weight: 500;
    font-size: 0.9rem;
}

.filters select {
    padding: 0.4rem 0.8rem;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-size: 0.9rem;
}

.filters button {
    padding: 0.4rem 1.2rem;
    background: #1a237e;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
}

.filters button:hover {
    background: #283593;
}

.chart-container {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 1.5rem;
}

.stats {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
}

.stats h2 {
    margin-bottom: 1rem;
    font-size: 1.1rem;
    color: #1a237e;
}

.stats table {
    width: 100%;
    border-collapse: collapse;
}

.stats th, .stats td {
    padding: 0.6rem 1rem;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.stats th {
    background: #f5f7fa;
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    color: #666;
}

.stats td {
    font-size: 0.9rem;
}

.no-data {
    text-align: center;
    color: #999;
    padding: 3rem;
    font-size: 1rem;
}

footer {
    text-align: center;
    padding: 1.5rem;
    color: #999;
    font-size: 0.8rem;
}