body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f5f5f5;
}

h1 {
    text-align: center;
    color: #333;
}

h2 {
    color: #555;
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.controls {
    text-align: center;
    margin-bottom: 15px;
}

.controls select {
    padding: 8px 16px;
    font-size: 14px;
    border: 2px solid #4bc0c0;
    border-radius: 4px;
    background: white;
    cursor: pointer;
    margin-right: 15px;
}

.controls button {
    padding: 8px 16px;
    margin: 0 5px;
    border: 2px solid #4bc0c0;
    background: white;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.2s;
}

.controls button:hover {
    background: #e0f7f7;
}

.controls button.active {
    background: #4bc0c0;
    color: white;
}

.controls-trend button {
    border-color: #9966ff;
}

.controls-trend button:hover {
    background: #f0e6ff;
}

.controls-trend button.active {
    background: #9966ff;
    color: white;
}

.chart-container {
    background: white;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}