:root {
    --bg-color: #f4f4f9;
    --card-bg: #ffffff;
    --text-color: #333;
    --accent-color: #2c974b;
    --border-color: #ddd;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 30px;
}

.controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--card-bg);
    padding: 15px 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

select {
    padding: 8px 12px;
    font-size: 16px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    min-width: 200px;
}

.time-range {
    display: flex;
    gap: 10px;
}

.range-btn {
    padding: 8px 16px;
    border: 1px solid var(--accent-color);
    background: transparent;
    color: var(--accent-color);
    border-radius: 4px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s;
}

.range-btn.active, .range-btn:hover {
    background: var(--accent-color);
    color: white;
}

.charts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 20px;
}

.chart-wrapper {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

h3 {
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.1em;
    color: #666;
}

canvas {
    width: 100% !important;
    height: 300px !important;
}