/* Knowledge Map — Dark theme force-directed graph */
:root {
    --km-bg: #0a0a1a;
    --km-panel: rgba(14, 14, 40, 0.9);
    --km-border: rgba(255, 255, 255, 0.06);
    --km-text: #e0e0e0;
    --km-text-dim: #8892a4;
    --km-accent: #00e5ff;
    --km-font: 'Segoe UI', 'Roboto', sans-serif;
    --km-font-mono: 'Cascadia Code', 'Fira Code', monospace;
}

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

body {
    background: var(--km-bg);
    font-family: var(--km-font);
    color: var(--km-text);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

/* Header */
.km-header {
    display: flex;
    align-items: center;
    gap: 1.25rem;
    padding: 0.6rem 1.5rem;
    background: var(--km-panel);
    border-bottom: 1px solid var(--km-border);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.km-back {
    color: var(--km-accent);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 600;
    white-space: nowrap;
}
.km-back:hover { text-decoration: underline; }

.km-header-text { display: flex; flex-direction: column; gap: 0.1rem; }

.km-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: #fff;
    line-height: 1.2;
}

.km-subtitle {
    font-size: 0.72rem;
    color: var(--km-text-dim);
    line-height: 1.2;
}

/* Canvas */
.km-canvas-wrap {
    position: fixed;
    top: 48px;
    left: 0;
    right: 0;
    bottom: 0;
}

#km-canvas {
    width: 100%;
    height: 100%;
    cursor: grab;
    display: block;
}
#km-canvas:active { cursor: grabbing; }

/* Stats bar (top-left) */
.km-stats {
    position: fixed;
    top: 58px;
    left: 1rem;
    display: flex;
    align-items: center;
    gap: 0.6rem;
    background: var(--km-panel);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 0.4rem 0.9rem;
    border-radius: 8px;
    border: 1px solid var(--km-border);
    z-index: 50;
    font-size: 0.75rem;
    color: var(--km-accent);
    font-family: var(--km-font-mono);
}

.km-stats-sep {
    color: var(--km-text-dim);
    font-size: 0.5rem;
}

/* Controls panel (top-right) */
.km-controls {
    position: fixed;
    top: 58px;
    right: 1rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--km-panel);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 0.4rem 0.6rem;
    border-radius: 8px;
    border: 1px solid var(--km-border);
    z-index: 50;
}

.km-btn {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--km-border);
    color: var(--km-text);
    padding: 0.35rem 0.65rem;
    border-radius: 6px;
    font-size: 0.78rem;
    cursor: pointer;
    transition: background 0.15s, border-color 0.15s;
    font-family: var(--km-font);
    line-height: 1;
    white-space: nowrap;
}
.km-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.12);
}
.km-btn-active {
    background: rgba(0, 229, 255, 0.12);
    border-color: rgba(0, 229, 255, 0.3);
    color: var(--km-accent);
}

.km-divider {
    width: 1px;
    height: 20px;
    background: var(--km-border);
    margin: 0 0.2rem;
}

.km-search {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--km-border);
    color: var(--km-text);
    padding: 0.35rem 0.65rem;
    border-radius: 6px;
    font-size: 0.78rem;
    width: 140px;
    font-family: var(--km-font);
}
.km-search::placeholder { color: var(--km-text-dim); }
.km-search:focus { outline: none; border-color: var(--km-accent); }

/* Legend (bottom-left) */
.km-legend {
    position: fixed;
    bottom: 1rem;
    left: 1rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem 0.9rem;
    background: var(--km-panel);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 0.55rem 0.9rem;
    border-radius: 8px;
    border: 1px solid var(--km-border);
    z-index: 50;
    max-width: calc(100vw - 2rem);
}

.km-legend-item {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-size: 0.7rem;
    color: var(--km-text-dim);
    cursor: pointer;
    transition: opacity 0.15s;
    user-select: none;
}
.km-legend-item:hover { color: var(--km-text); }
.km-legend-item.dimmed { opacity: 0.25; }

.km-legend-dot {
    width: 9px;
    height: 9px;
    border-radius: 50%;
    flex-shrink: 0;
}

/* Tooltip */
.km-tooltip {
    position: fixed;
    z-index: 200;
    background: rgba(10, 10, 30, 0.95);
    border: 1px solid var(--km-border);
    border-radius: 8px;
    padding: 0.7rem 0.9rem;
    pointer-events: none;
    max-width: 260px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    transition: opacity 0.12s;
}
.km-tooltip[hidden] { display: block; opacity: 0; pointer-events: none; }

.km-tooltip-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 0.25rem;
}

.km-tooltip-type {
    font-size: 0.65rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--km-accent);
    margin-bottom: 0.35rem;
}

.km-tooltip-body {
    font-size: 0.72rem;
    color: var(--km-text-dim);
    line-height: 1.4;
}

.km-tooltip-list {
    list-style: none;
    padding: 0;
    margin: 0.3rem 0 0;
}
.km-tooltip-list li {
    font-size: 0.7rem;
    color: var(--km-text-dim);
    padding: 0.1rem 0;
}
.km-tooltip-list li::before {
    content: '\2022';
    color: var(--km-accent);
    margin-right: 0.35rem;
}

/* Responsive */
@media (max-width: 768px) {
    .km-header { gap: 0.6rem; padding: 0.5rem 0.75rem; }
    .km-title { font-size: 0.95rem; }
    .km-subtitle { font-size: 0.65rem; }
    .km-controls { flex-wrap: wrap; gap: 0.3rem; right: 0.5rem; top: 54px; }
    .km-search { width: 100px; }
    .km-stats { left: 0.5rem; top: 54px; font-size: 0.65rem; }
    .km-legend { gap: 0.3rem 0.6rem; padding: 0.4rem 0.7rem; font-size: 0.6rem; }
}

@media (max-width: 480px) {
    .km-controls {
        flex-wrap: wrap;
        max-width: 180px;
    }
    .km-stats {
        font-size: 0.6rem;
        max-width: calc(100vw - 200px);
        flex-wrap: wrap;
    }
    .km-stats-sep { display: none; }
}