body {
    font-family: 'Roboto Mono', monospace;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    height: 100vh;
    background: linear-gradient(135deg, #1a1a2e, #16213e);
    color: #e0e0e0;
}

header {
    background: linear-gradient(90deg, #0f3460, #16213e);
    color: #00d4ff;
    text-align: center;
    padding: 20px 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
    border-bottom: 3px solid #00d4ff;
}

header h1 {
    margin: 0;
    font-size: 2.8rem;
    letter-spacing: 2px;
    text-shadow: 0 0 10px #00d4ff, 0 0 20px #00d4ff;
}

header p {
    margin: 5px 0 0;
    font-size: 1.2rem;
    font-weight: 300;
    color: #a6e3ff;
}

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

#controls {
    margin-bottom: 20px;
    text-align: center;
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: center;
}

#file-input, #load-sample, #view-level, #search-box {
    padding: 12px 20px;
    font-size: 14px;
    border: 1px solid #00d4ff;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
    background: linear-gradient(90deg, #16213e, #1a1a2e);
    color: #00d4ff;
    text-shadow: 0 0 5px #00d4ff;
}

#file-input:hover, #load-sample:hover, #view-level:hover, #search-box:focus {
    background: linear-gradient(90deg, #1a1a2e, #16213e);
    box-shadow: 0 4px 8px rgba(0, 212, 255, 0.5);
    transform: translateY(-2px);
    outline: none;
}

#file-input::-webkit-file-upload-button {
    display: none;
}

#search-box::placeholder {
    color: #a6e3ff;
    opacity: 0.7;
}

#graph-container {
    width: 100%;
    max-width: 1200px;
    height: 70vh;
    border: 1px solid #00d4ff;
    background: linear-gradient(135deg, #0f3460, #1a1a2e);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.5);
    border-radius: 15px;
    overflow: hidden;
    position: relative;
}

footer {
    background: linear-gradient(90deg, #0f3460, #16213e);
    color: #00d4ff;
    text-align: center;
    padding: 15px 0;
    font-size: 0.9rem;
    box-shadow: 0 -4px 6px rgba(0, 0, 0, 0.5);
}

.links line {
    stroke: #00d4ff;
    stroke-width: 2;
    transition: stroke 0.3s ease;
    marker-end: url(#arrowhead);
}

.links line:hover {
    stroke: #00ffab;
}

.nodes circle {
    transition: fill 0.3s ease, stroke 0.3s ease, transform 0.2s ease;
    fill: #00d4ff;
    stroke: #00ffab;
}

.nodes circle:hover {
    fill: #00ffab;
    stroke: #00d4ff;
}

.nodes circle.root {
    fill: #ff5722; /* Highlight color for root nodes */
    stroke: #ff8a50;
    transition: fill 0.3s ease, stroke 0.3s ease;
}

.nodes circle.inferred {
    fill: grey;
    stroke: darkgrey;
    transition: fill 0.3s ease, stroke 0.3s ease;
}

.nodes circle.root:hover {
    fill: #ff8a50;
    stroke: #ff5722;
}

.labels text {
    font-family: 'Roboto Mono', monospace;
    font-size: 12px;
    fill: #e0e0e0;
    pointer-events: none;
}

.tooltip {
    max-width: 360px;
    box-sizing: border-box;
    font-family: 'Roboto Mono', monospace;
    font-size: 14px;
    color: #e0e0e0;
    background: linear-gradient(135deg, #1a1a2e, #0f3460);
    border: 1px solid #00d4ff;
    border-radius: 8px;
    padding: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.5);
    position: absolute;
    display: none;
    flex-direction: column;
    gap: 4px;
    z-index: 10;
    animation: fadeIn 0.3s ease;
}

.tooltip p {
    margin: 0;
    word-break: break-word;
    overflow-wrap: break-word;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

#file-name-display {
    position: absolute;
    top: 0;
    right: 0;
    font-family: 'Roboto Mono', monospace;
    color: #00d4ff;
    text-shadow: 0 0 5px #00d4ff, 0 0 10px #00d4ff;
    border-left: 1px solid #00d4ff;
    border-bottom: 1px solid #00d4ff;
    backdrop-filter: blur(5px);
    padding: 12px 20px;
    border-radius: 0 0 0 15px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.5);
    z-index: 100;
    pointer-events: none;
}