body {
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
    background-color: #f0f0f0;
    position: relative;
}

#network {
    width: 100%;
    height: 500px;
    border: 1px solid #ccc;
    background-color: white;
    position: relative;
}

#title-overlay {
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    font-size: 18px;
    font-weight: bold;
    color: #2c3e50;
    background: rgba(255, 255, 255, 0.85);
    padding: 4px 16px;
    border-radius: 4px;
    pointer-events: none;
}

#legend {
    position: absolute;
    top: 40px;
    left: 10px;
    z-index: 10;
    background: rgba(255, 255, 255, 0.92);
    border: 1px solid #ccc;
    border-radius: 6px;
    padding: 8px 12px;
    font-size: 13px;
    line-height: 1.6;
    pointer-events: none;
}

.legend-title {
    font-weight: bold;
    margin-bottom: 4px;
    color: #2c3e50;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
}

.legend-dot {
    display: inline-block;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    flex-shrink: 0;
}

.controls {
    padding: 8px 12px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    background: #f0f0f0;
}

.controls button {
    padding: 6px 16px;
    font-size: 14px;
    cursor: pointer;
    border: 1px solid #999;
    border-radius: 4px;
    background: #fff;
}

.controls button:hover {
    background: #e0e0e0;
}

#node-info {
    font-size: 13px;
    color: #555;
    font-style: italic;
}