:root {
    /* Code Knowledge Graph Theme */
    --clr-bg: #0D1117;
    --clr-surface: #161B22;
    --clr-surface-hover: #21262D;
    --clr-border: #30363D;
    
    --clr-primary: #7C3AED;
    --clr-primary-glow: rgba(124, 58, 237, 0.4);
    --clr-accent: #22D3EE;
    
    --clr-text-main: #C9D1D9;
    --clr-text-muted: #8B949E;
    
    --clr-node-class: #F97316;
    --clr-node-function: #3B82F6;
    --clr-node-module: #10B981;
    --clr-node-variable: #F43F5E;
    
    --font-sans: 'Inter', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --radius-sm: 6px;
    --radius-md: 10px;
    
    --transition: all 0.2s ease;
}

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

body {
    background-color: var(--clr-bg);
    color: var(--clr-text-main);
    font-family: var(--font-sans);
    height: 100vh;
    overflow: hidden;
}

/* Utilities */
.hidden { display: none !important; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }
.mt-6 { margin-top: 1.5rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }
.ml-2 { margin-left: 0.5rem; }
.w-full { width: 100%; }
.text-xs { font-size: 0.75rem; }
.text-sm { font-size: 0.85rem; }
.text-muted { color: var(--clr-text-muted); }
.uppercase { text-transform: uppercase; letter-spacing: 0.05em; }
.mono { font-family: var(--font-mono); }

/* Buttons */
.btn {
    padding: 0.6rem 1rem;
    border-radius: var(--radius-sm);
    font-weight: 500;
    font-size: 0.85rem;
    font-family: inherit;
    cursor: pointer;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}
.btn-sm { padding: 0.4rem 0.75rem; font-size: 0.75rem; }
.btn-outline { background: transparent; border: 1px solid var(--clr-border); color: var(--clr-text-main); }
.btn-outline:hover { background: var(--clr-surface-hover); border-color: var(--clr-text-muted); }
.btn-primary { background: var(--clr-primary); color: #FFF; box-shadow: 0 4px 12px var(--clr-primary-glow); }
.btn-primary:hover { filter: brightness(1.2); transform: translateY(-1px); }
.btn-icon { padding: 0.4rem; background: transparent; color: var(--clr-text-muted); border: 1px solid transparent; border-radius: var(--radius-sm); cursor: pointer; display: flex; align-items: center; justify-content: center; }
.btn-icon:hover { background: var(--clr-surface-hover); color: var(--clr-text-main); border-color: var(--clr-border); }

.glass-panel {
    background: rgba(22, 27, 34, 0.7);
    backdrop-filter: blur(12px);
    border: 1px solid var(--clr-border);
}

.badge {
    padding: 0.2rem 0.5rem;
    border-radius: 12px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    background: rgba(255,255,255,0.1);
}

/* Layout */
.app-layout {
    display: flex;
    height: 100vh;
    width: 100vw;
}

.sidebar {
    width: 320px;
    height: 100%;
    border-right: 1px solid var(--clr-border);
    border-top: none; border-bottom: none; border-left: none;
    z-index: 10;
    display: flex;
    flex-direction: column;
}

.brand {
    padding: 1.5rem 1.5rem 0.5rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--clr-primary);
}
.brand h1 { font-size: 1.2rem; font-weight: 600; color: #FFF; }
.subtitle { padding: 0 1.5rem; font-size: 0.85rem; color: var(--clr-text-muted); }

.editor-section { padding: 0 1.5rem; flex-shrink: 0; }
.label { font-size: 0.8rem; font-weight: 600; color: var(--clr-text-muted); }

.editor {
    width: 100%;
    min-height: 250px;
    background: rgba(0,0,0,0.4);
    border: 1px solid var(--clr-border);
    border-radius: var(--radius-sm);
    color: var(--clr-text-main);
    padding: 1rem;
    font-size: 0.8rem;
    line-height: 1.5;
    resize: vertical;
    outline: none;
}
.editor:focus { border-color: var(--clr-primary); box-shadow: 0 0 0 1px var(--clr-primary); }

.filter-section {
    padding: 1.5rem;
    border-top: 1px solid var(--clr-border);
    flex-grow: 1;
    overflow-y: auto;
}
.section-title { font-size: 0.9rem; font-weight: 600; color: #FFF; }
.search-input { width: 100%; background: var(--clr-surface); border: 1px solid var(--clr-border); padding: 0.5rem; border-radius: var(--radius-sm); color: #FFF; outline: none; }
.search-input:focus { border-color: var(--clr-accent); }

.legend-item { display: flex; align-items: center; gap: 0.5rem; font-size: 0.85rem; margin-bottom: 0.4rem; }
.legend-color { width: 10px; height: 10px; border-radius: 50%; }
.legend-color.class { background: var(--clr-node-class); }
.legend-color.function { background: var(--clr-node-function); }
.legend-color.module { background: var(--clr-node-module); }
.legend-color.variable { background: var(--clr-node-variable); }

.stats { background: rgba(0,0,0,0.2); padding: 0.75rem; border-radius: var(--radius-sm); border: 1px solid var(--clr-border); }
.stat-row { display: flex; justify-content: space-between; font-size: 0.85rem; margin-bottom: 0.25rem; }
.stat-row:last-child { margin-bottom: 0; }
.stat-lbl { color: var(--clr-text-muted); }

/* Main Visualizer Area */
.visualizer {
    flex: 1;
    position: relative;
    display: flex;
    flex-direction: column;
}

.vis-header {
    height: 60px;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--clr-border);
    background: var(--clr-bg);
    z-index: 10;
}
.vis-header h2 { font-size: 1rem; font-weight: 500; color: #FFF; }
.toolbar { display: flex; }

.canvas-wrapper {
    flex: 1;
    position: relative;
    overflow: hidden;
    background-image: radial-gradient(var(--clr-border) 1px, transparent 1px);
    background-size: 30px 30px;
    /* Neon glow behind graph */
    box-shadow: inset 0 0 100px rgba(124, 58, 237, 0.05);
}

.empty-state {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    color: var(--clr-text-muted);
    text-align: center;
    pointer-events: none;
}

/* D3 SVG Styles injected by graph.js */
.node circle { stroke: var(--clr-bg); stroke-width: 2px; cursor: pointer; transition: stroke 0.2s, filter 0.2s; }
.node circle:hover { stroke: #FFF; filter: drop-shadow(0 0 6px rgba(255,255,255,0.8)); }
.node text { font-family: var(--font-mono); font-size: 12px; fill: var(--clr-text-main); pointer-events: none; text-shadow: 0 1px 3px #000; }
.node.dimmed circle { opacity: 0.2; }
.node.dimmed text { opacity: 0.2; }

.link { stroke: var(--clr-border); stroke-opacity: 0.6; stroke-width: 1.5px; fill: none; transition: stroke-opacity 0.2s; }
.link.active { stroke: var(--clr-accent); stroke-opacity: 1; stroke-width: 2.5px; filter: drop-shadow(0 0 4px var(--clr-accent)); }
.link.dimmed { stroke-opacity: 0.1; }

.link-arrow { fill: var(--clr-border); }
.link.active .link-arrow { fill: var(--clr-accent); }

/* Node Detail Overlay */
.node-panel {
    position: absolute;
    top: 20px; right: 20px;
    width: 320px;
    max-height: calc(100vh - 100px);
    overflow-y: auto;
    border-radius: var(--radius-md);
    padding: 1.5rem;
    z-index: 20;
    box-shadow: 0 10px 40px rgba(0,0,0,0.8);
    border: 1px solid var(--clr-border);
}
.panel-header { display: flex; justify-content: space-between; align-items: flex-start; }
.nd-name { font-size: 1.1rem; color: #FFF; word-break: break-all; line-height: 1.3; }

.connections-list { list-style: none; display: flex; flex-direction: column; gap: 0.5rem; }
.connections-list li {
    background: rgba(0,0,0,0.3);
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-family: var(--font-mono);
    border-left: 3px solid;
    cursor: pointer;
    transition: var(--transition);
}
.connections-list li:hover { background: var(--clr-surface-hover); }

/* Colors for Node Details */
.connections-list li.edge-outgoing { border-color: var(--clr-accent); }
.connections-list li.edge-incoming { border-color: var(--clr-primary); }

@media (max-width: 800px) {
    .app-layout { flex-direction: column; }
    .sidebar { width: 100%; height: auto; max-height: 50vh; border-bottom: 1px solid var(--clr-border); padding-bottom: 1rem; overflow-y: auto;}
    .visualizer { flex: 1; }
    .node-panel { left: 20px; bottom: 20px; top: auto; width: calc(100% - 40px); }
    .editor-section { padding-bottom: 1rem; }
}