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

:root {
    --bg-primary: #fafafa;
    --bg-secondary: #ffffff;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    min-height: 100vh;
    padding: 0;
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 1600px;
    margin: 0 auto;
    background: var(--bg-secondary);
    min-height: 100vh;
}

header {
    border-bottom: 1px solid var(--border-color);
    padding: 2rem 3rem;
    background: var(--bg-secondary);
}

header h1 {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    font-weight: 400;
}

.upload-section {
    padding: 3rem;
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 4px;
    padding: 4rem 2rem;
    text-align: center;
    background: var(--bg-primary);
    cursor: pointer;
    transition: border-color 0.2s ease, background-color 0.2s ease;
}

.upload-area:hover {
    border-color: var(--accent);
    background: #f8fafc;
}

.upload-area.dragover {
    border-color: var(--accent);
    background: #eff6ff;
}

.upload-content svg {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    opacity: 0.6;
}

.upload-content p {
    margin: 0.5rem 0;
    color: var(--text-primary);
    font-size: 0.9375rem;
    font-weight: 500;
}

.upload-hint {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.file-name {
    margin-top: 1rem;
    font-weight: 500;
    color: var(--accent);
    font-size: 0.875rem;
}

.loading {
    text-align: center;
    padding: 4rem 2rem;
}

.spinner {
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--accent);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 1rem;
}

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

.loading p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.error-message {
    background: #fef2f2;
    color: var(--error);
    padding: 1rem 1.25rem;
    border-radius: 4px;
    margin: 1.5rem 3rem;
    border-left: 3px solid var(--error);
    font-size: 0.875rem;
}

.dashboard {
    padding: 0 3rem 3rem;
}

.controls {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    margin-bottom: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.btn {
    padding: 0.625rem 1.25rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.btn:hover {
    background: var(--bg-primary);
}

.btn-primary {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

.btn-primary:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
}

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-secondary);
}

.btn-secondary:hover {
    background: var(--bg-primary);
    color: var(--text-primary);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.summary-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
    margin-bottom: 3rem;
}

.stat-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    border-radius: 4px;
    text-align: left;
}

.stat-card h3 {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-card .value {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.2;
}

.chart-section {
    margin-bottom: 4rem;
}

.chart-section h2 {
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.chart-container {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.radar-charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
    gap: 1.5rem;
}

.radar-chart-item {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.radar-chart-item h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    text-align: left;
    font-size: 1rem;
    font-weight: 600;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

@media (max-width: 1024px) {
    header {
        padding: 1.5rem 2rem;
    }

    .upload-section {
        padding: 2rem;
    }

    .dashboard {
        padding: 0 2rem 2rem;
    }

    .error-message {
        margin: 1.5rem 2rem;
    }
}

@media (max-width: 768px) {
    header {
        padding: 1.25rem 1.5rem;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .upload-section {
        padding: 1.5rem;
    }

    .upload-area {
        padding: 3rem 1.5rem;
    }

    .dashboard {
        padding: 0 1.5rem 1.5rem;
    }

    .error-message {
        margin: 1rem 1.5rem;
    }

    .radar-charts-grid {
        grid-template-columns: 1fr;
    }

    .controls {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}