:root {
    color-scheme: dark;
    --t-bg: #0b0e11;
    --t-panel: #181a20;
    --t-canvas: #131820;
    --t-header: #12151c;
    --t-surface: #1e2128;
    --t-hover: #22262f;
    --t-border: #2b3139;
    --t-text: #eaecef;
    --t-text-dim: #848e9c;
    --t-text-bright: #ffffff;
    --t-accent: #fcd535;
    --t-accent-hover: #f0c232;
    --t-accent-text: #0b0e11;
    --t-green: #0ecb81;
    --socket-stroke: #eaecef;
}

:root[data-bs-theme="light"] {
    color-scheme: light;
    --t-bg: #f5f7fa;
    --t-panel: #ffffff;
    --t-canvas: #f5f7fa;
    --t-header: #f8fafc;
    --t-surface: #ffffff;
    --t-hover: #f1f5f9;
    --t-border: #e2e8f0;
    --t-text: #1e293b;
    --t-text-dim: #64748b;
    --t-text-bright: #0f172a;
    --t-accent: #d97706;
    --t-accent-hover: #b45309;
    --t-accent-text: #ffffff;
    --t-green: #16a34a;
    --socket-stroke: #1e2329;
}

* { box-sizing: border-box; }
html, body { width: 100%; height: 100%; margin: 0; }

body {
    display: grid;
    grid-template-rows: 52px minmax(0, 1fr) 25px;
    overflow: hidden;
    background: var(--t-bg);
    color: var(--t-text);
    font: 13px/1.4 'IBM Plex Mono', 'Cascadia Code', 'Consolas', monospace;
}

button, input { font: inherit; }

.demo-header {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
    padding: 0 16px;
    background: var(--t-header);
    border-bottom: 1px solid var(--t-border);
}

.brand {
    color: var(--t-text-bright);
    font-size: 15px;
    font-weight: 700;
    white-space: nowrap;
}

.model-stats {
    color: var(--t-text-dim);
    font-size: 11px;
    white-space: nowrap;
}

.spacer { flex: 1; }

.toolbar-cluster {
    display: inline-flex;
    align-items: center;
    gap: 3px;
}

.tbtn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border: 1px solid var(--t-border);
    border-radius: 6px;
    background: transparent;
    color: var(--t-text);
    cursor: pointer;
    font-size: 12px;
    white-space: nowrap;
}

.tbtn:hover:not(:disabled) {
    border-color: var(--t-accent);
    color: var(--t-accent);
}

.tbtn:disabled { cursor: default; opacity: .35; }
.tbtn:focus-visible { outline: 2px solid var(--t-accent); outline-offset: 1px; }
.tbtn.icon-only {
    width: 30px;
    height: 30px;
    justify-content: center;
    flex: 0 0 30px;
    padding: 0;
}
.tbtn svg {
    width: 16px;
    height: 16px;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}
.theme-dark-icon { display: none; }
#themeBtn.is-light .theme-light-icon { display: none; }
#themeBtn.is-light .theme-dark-icon { display: block; }
.tbtn.primary, .tbtn.on {
    border-color: var(--t-accent);
    background: var(--t-accent);
    color: var(--t-accent-text);
}

.indicator-dialog {
    width: min(460px, calc(100vw - 32px));
    padding: 0;
    border: 1px solid var(--t-border);
    border-radius: 10px;
    background: var(--t-panel);
    color: var(--t-text);
    box-shadow: 0 24px 80px rgba(0, 0, 0, .45);
}

.indicator-dialog::backdrop { background: rgba(3, 7, 18, .68); }
.indicator-dialog form { padding: 22px; }
.indicator-dialog h2 { margin: 4px 0 8px; color: var(--t-text-bright); font-size: 19px; }
.indicator-dialog p { margin: 0 0 20px; color: var(--t-text-dim); font-size: 11px; }
.indicator-dialog code { color: var(--t-accent); }
.dialog-kicker { color: var(--t-accent); font-size: 10px; font-weight: 700; letter-spacing: .8px; }
.dialog-field { display: grid; gap: 7px; color: var(--t-text-dim); font-size: 11px; }
.dialog-field input:not([type="checkbox"]),
.dialog-field select {
    width: 100%;
    padding: 9px 10px;
    border: 1px solid var(--t-border);
    border-radius: 6px;
    outline: none;
    background: var(--t-bg);
    color: var(--t-text-bright);
}
.dialog-field input:focus,
.dialog-field select:focus { border-color: var(--t-accent); }
.dialog-port-settings {
    display: grid;
    gap: 13px;
    margin: 18px 0 0;
    padding: 14px;
    border: 1px solid var(--t-border);
    border-radius: 7px;
}
.dialog-port-settings legend { padding: 0 6px; color: var(--t-text-bright); font-size: 11px; font-weight: 700; }
.dialog-port-settings small { color: var(--t-text-dim); font-size: 10px; line-height: 1.45; }
.dialog-check { display: flex; align-items: center; gap: 9px; color: var(--t-text); font-size: 11px; }
.dialog-check input { width: 15px; height: 15px; margin: 0; accent-color: var(--t-accent); }
.dialog-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 22px; }

.diagram-workspace {
    display: grid;
    grid-template-columns: 245px minmax(0, 1fr);
    min-width: 0;
    min-height: 0;
    background: var(--t-border);
    gap: 1px;
}

.palette-panel {
    min-width: 0;
    overflow: auto;
    background: var(--t-panel);
}

.panel-head,
.canvas-caption {
    display: flex;
    align-items: center;
    gap: 10px;
    height: 31px;
    padding: 0 10px;
    border-bottom: 1px solid var(--t-border);
    background: var(--t-header);
    color: var(--t-text-bright);
    font-size: 11px;
    font-weight: 700;
    letter-spacing: .35px;
    text-transform: uppercase;
}

.panel-hint {
    margin-left: auto;
    color: var(--t-text-dim);
    font-size: 9px;
    font-weight: 400;
    letter-spacing: 0;
    text-transform: none;
}

.palette-search-wrap {
    padding: 8px;
    border-bottom: 1px solid var(--t-border);
}

.palette-search {
    width: 100%;
    padding: 7px 9px;
    border: 1px solid var(--t-border);
    border-radius: 4px;
    outline: none;
    background: var(--t-bg);
    color: var(--t-text);
    font-size: 11px;
}

.palette-search:focus { border-color: var(--t-accent); }

.d-palette { padding: 4px 0; }
.d-palette-tree, .d-palette-group-items { margin: 0; padding: 0; list-style: none; }
.d-palette-group { margin: 2px 0; }
.d-palette-group.is-hidden, .d-palette-item.is-hidden { display: none; }

.d-palette-group-head {
    display: flex;
    align-items: center;
    gap: 6px;
    width: 100%;
    padding: 5px 10px;
    border: 0;
    background: transparent;
    color: var(--t-text-dim);
    cursor: pointer;
    text-align: left;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: .5px;
    text-transform: uppercase;
}

.d-palette-group-head:hover { background: var(--t-hover); color: var(--t-text-bright); }

.d-palette-chev {
    width: 0;
    height: 0;
    flex: none;
    border-top: 4px solid transparent;
    border-bottom: 4px solid transparent;
    border-left: 5px solid currentColor;
    transform: rotate(90deg);
    transition: transform 120ms ease;
}

.d-palette-group.is-collapsed .d-palette-chev { transform: rotate(0); }
.d-palette-group.is-collapsed .d-palette-group-items { display: none; }

.d-palette-item {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 5px 10px 5px 26px;
    color: var(--t-text);
    cursor: grab;
    font-size: 11px;
    user-select: none;
}

.d-palette-item:hover { background: var(--t-hover); color: var(--t-text-bright); }
.d-palette-item:focus-visible { outline: 2px solid var(--t-accent); outline-offset: -2px; }
.d-palette-item.is-selected { background: color-mix(in srgb, var(--t-accent) 18%, transparent); color: var(--t-text-bright); }
.d-palette-item.is-dragging { cursor: grabbing; opacity: .5; }
.d-palette-icon { width: 17px; height: 17px; flex: none; object-fit: contain; }
.d-palette-icon-placeholder { border-radius: 3px; background: var(--t-surface); }
.d-palette-label { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.canvas-panel {
    position: relative;
    min-width: 0;
    min-height: 0;
    overflow: hidden;
    background: var(--t-canvas);
}

.canvas-caption {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 10px;
    z-index: 2;
    top: 0;
    right: 0;
    left: 0;
    height: 31px;
    padding: 0 8px 0 12px;
    pointer-events: none;
    background: color-mix(in srgb, var(--t-header) 92%, transparent);
}

.canvas-caption .symbol { color: var(--t-accent); }
.canvas-caption span:not(.symbol) { color: var(--t-text-dim); font-weight: 400; }

.canvas-panel:fullscreen { width: 100%; height: 100%; }

#diagram {
    position: absolute;
    inset: 31px 0 0;
    background: var(--t-canvas);
}

.canvas-help {
    position: absolute;
    right: 12px;
    bottom: 11px;
    z-index: 2;
    padding: 5px 8px;
    border: 1px solid var(--t-border);
    border-radius: 4px;
    background: color-mix(in srgb, var(--t-header) 88%, transparent);
    color: var(--t-text-dim);
    font-size: 10px;
    pointer-events: none;
}

.statusbar {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
    padding: 0 10px;
    overflow: hidden;
    border-top: 1px solid var(--t-border);
    background: var(--t-header);
    color: var(--t-text-dim);
    font-size: 10px;
    white-space: nowrap;
}

.status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--t-green);
}

@media (max-width: 900px) {
    .model-stats, #resetBtn, #readonlyBtn, .error-demo-btn { display: none; }
    .demo-header { gap: 6px; padding: 0 8px; }
    .tbtn { padding: 5px 8px; }
    .diagram-workspace { grid-template-columns: 190px minmax(0, 1fr); }
}

@media (max-width: 650px) {
    body { grid-template-rows: auto minmax(0, 1fr) 25px; }
    .demo-header { min-height: 52px; flex-wrap: wrap; padding: 7px 8px; }
    .brand { width: 100%; font-size: 13px; }
    .diagram-workspace { grid-template-columns: 1fr; }
    .palette-panel { display: none; }
}