:root {
    --primary-color: #ff0000;
    --secondary-color: #2196f3;
    --background-color: #f5f5f5;
    --card-background: #ffffff;
    --text-color: #333333;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--background-color);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background-color: var(--card-background);
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

header img {
    max-width: 200px;
    height: auto;
    margin-bottom: 1rem;
}

header h1 {
    color: var(--primary-color);
    margin: 0.5rem 0;
    font-size: 2.2rem;
}

header p {
    color: #666;
    font-size: 1.1rem;
}

.test-button {
    display: block;
    width: 220px;
    margin: 2rem auto;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    font-weight: bold;
    color: white;
    background-color: var(--primary-color);
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.test-button:hover {
    background-color: #e00000;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.test-button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.chart-container {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    margin: 2rem 0;
    height: 400px;
}

.metrics {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.metric-card {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    text-align: center;
}

.metric-card h3 {
    color: var(--secondary-color);
    margin-bottom: 0.8rem;
    font-size: 1.2rem;
}

.metric-card div {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--text-color);
}

.loading-spinner {
    display: none;
    width: 40px;
    height: 40px;
    margin: 20px auto;
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.error-message {
    display: none;
    background-color: #ffebee;
    color: #d32f2f;
    padding: 1rem;
    margin: 1rem 0;
    border-radius: 8px;
    text-align: center;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (max-width: 768px) {
    .container {
        padding: 15px;
    }

    .metrics {
        grid-template-columns: 1fr;
    }
}