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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

header h1 {
    font-size: 28px;
    margin-bottom: 10px;
}

header p {
    font-size: 14px;
    opacity: 0.9;
}

.settings-panel {
    padding: 30px;
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #333;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 6px;
    font-size: 14px;
    transition: border-color 0.3s;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
}

.form-group input[type="number"] {
    width: 150px;
}

.btn-primary,
.btn-secondary {
    padding: 12px 24px;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 100%;
    margin-top: 10px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background: #6c757d;
    color: white;
    margin-left: 10px;
}

.btn-secondary:hover {
    background: #5a6268;
}

.status-message {
    margin-left: 10px;
    font-size: 12px;
    color: #28a745;
}

.progress-container {
    padding: 20px 30px;
    background: #fff3cd;
    border-bottom: 1px solid #ffeaa7;
}

.progress-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    font-size: 14px;
    color: #856404;
}

.progress-bar {
    width: 100%;
    height: 24px;
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    transition: width 0.3s ease;
    width: 0%;
}

.error-container {
    padding: 20px 30px;
    background: #f8d7da;
    border-bottom: 1px solid #f5c6cb;
    color: #721c24;
}

.visualization-container {
    padding: 20px;
    background: #fafafa;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
}

#graph {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    width: 100%;
    height: auto;
    max-width: 1200px;
    aspect-ratio: 3 / 2;
}

.links line {
    stroke: #999;
    stroke-opacity: 0.6;
}

.nodes circle {
    stroke: #fff;
    stroke-width: 1.5px;
    cursor: pointer;
}

.nodes circle:hover {
    stroke-width: 3px;
    stroke: #667eea;
}

.nodes text {
    font-family: sans-serif;
    font-size: 10px;
    pointer-events: none;
    user-select: none;
}

.info-panel {
    padding: 30px;
    background: white;
    border-top: 1px solid #e0e0e0;
}

.info-panel h3 {
    margin-bottom: 15px;
    color: #333;
}

#statsContainer p {
    margin: 8px 0;
    color: #666;
    font-size: 14px;
}

#statsContainer span {
    font-weight: 600;
    color: #667eea;
}

.file-info {
    margin-top: 8px;
}

.file-info small {
    color: #666;
    font-size: 12px;
}

.form-group input[type="file"] {
    padding: 8px;
    cursor: pointer;
}

.file-preview {
    margin-top: 20px;
    padding: 15px;
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 6px;
    max-height: 300px;
    overflow-y: auto;
}

.file-preview h4 {
    margin-bottom: 10px;
    color: #333;
    font-size: 14px;
}

.file-preview table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
}

.file-preview th,
.file-preview td {
    padding: 8px;
    border: 1px solid #e0e0e0;
    text-align: left;
}

.file-preview th {
    background: #f8f9fa;
    font-weight: 600;
    color: #333;
}

.file-preview td {
    color: #666;
}

@media (max-width: 768px) {
    .container {
        border-radius: 0;
    }

    header h1 {
        font-size: 22px;
    }

    .settings-panel {
        padding: 20px;
    }

    #graph {
        aspect-ratio: 1 / 1;
    }
}