/* ============================================================================
 * AI STUDIO — v4 Runway-style redesign
 *
 * 关键 token：
 *   --ais-level0/1/2/3-bg  → 三层深度
 *   --ais-handle-text/image/video/audio → handle / edge 类型色
 *   --ais-radius: 10px
 *
 * 结构：
 *   - 左侧 64px 折叠 sidebar
 *   - 顶部 header (back / title / last saved / Run all)
 *   - 中央画布 (grid + nodes + bezier edges)
 *   - 底部浮动 toolbar (pointer / zoom / undo)
 *
 * 节点：header (icon+title+gear+menu) / body (content + exec history) / footer (Run + ∞)
 * ============================================================================ */

:root {
    --ais-level0-bg: #0a0a0a;
    --ais-level1-bg: #131313;
    --ais-level2-bg: #1a1a1a;
    --ais-level3-bg: #222;
    --ais-border:    #2a2a2a;
    --ais-border-strong: #3a3a3a;
    --ais-text:      #e8e8e8;
    --ais-text-muted: #888;
    --ais-text-dim:  #555;
    --ais-accent:    #f472b6;
    --ais-accent-soft: rgba(244, 114, 182, 0.18);
    --ais-success:   #4ade80;
    --ais-warning:   #fbbf24;
    --ais-danger:    #f87171;

    --ais-handle-text:  #c084fc;
    --ais-handle-image: #60a5fa;
    --ais-handle-video: #fbbf24;
    --ais-handle-audio: #4ade80;
    --ais-handle-any:   #888;

    --ais-radius: 10px;
    --ais-radius-sm: 6px;
    --ais-shadow-lg: 0 12px 32px rgba(0,0,0,0.5);
    --ais-shadow-node: 0 4px 14px rgba(0,0,0,0.45);

    --ais-sidebar-w: 64px;
    --ais-header-h: 52px;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; background: var(--ais-level0-bg); color: var(--ais-text); font-family: system-ui, -apple-system, "Segoe UI", "Noto Sans SC", sans-serif; overflow: hidden; }

/* ============ Top global nav ============ */
.global-top-nav {
    height: 40px; flex-shrink: 0;
    display: flex; align-items: center; gap: 16px;
    padding: 0 16px;
    background: var(--ais-level1-bg);
    border-bottom: 1px solid var(--ais-border);
    z-index: 100; position: relative;
}
.global-top-nav .brand-mini { font-size: 13px; font-weight: 600; letter-spacing: 1px; color: #ccc; }
.global-top-nav .brand-mini .brand-h { color: var(--ais-accent); }
.global-nav-links { display: flex; gap: 4px; flex: 1; }
.global-nav-link {
    color: var(--ais-text-muted); text-decoration: none; font-size: 12px;
    padding: 6px 12px; border-radius: 6px;
    display: inline-flex; align-items: center; gap: 6px;
    transition: background 0.15s, color 0.15s;
}
.global-nav-link:hover { background: rgba(255,255,255,0.04); color: #ccc; }
.global-nav-link.active { color: var(--ais-accent); background: var(--ais-accent-soft); }
.global-top-right { display: flex; align-items: center; gap: 8px; }

/* ============ Shell ============ */
.ais-shell {
    display: grid;
    grid-template-columns: var(--ais-sidebar-w) 1fr;
    grid-template-rows: var(--ais-header-h) 1fr;
    height: calc(100vh - 40px);
    overflow: hidden;
}

/* ============ Sidebar (64px) ============ */
.ais-sidebar {
    grid-column: 1; grid-row: 1 / 3;
    background: var(--ais-level1-bg);
    border-right: 1px solid var(--ais-border);
    display: flex; flex-direction: column;
    overflow: hidden;
}
.ais-sb-section {
    display: flex; flex-direction: column; align-items: center;
    padding: 8px 0; gap: 4px;
}
.ais-sb-section.divided { border-bottom: 1px solid var(--ais-border); }
.ais-sb-btn {
    width: 48px; padding: 8px 4px;
    background: transparent; border: none;
    color: var(--ais-text-muted);
    border-radius: var(--ais-radius-sm);
    cursor: pointer;
    display: flex; flex-direction: column; align-items: center; gap: 4px;
    font-size: 9px; line-height: 1;
    transition: background 0.15s, color 0.15s;
    position: relative;
    font-family: inherit;
}
.ais-sb-btn i { font-size: 18px; }
.ais-sb-btn:hover { background: rgba(255,255,255,0.05); color: #ddd; }
.ais-sb-btn[data-active="true"] { background: var(--ais-accent-soft); color: var(--ais-accent); }
.ais-sb-btn[data-active="true"]::before {
    content: ''; position: absolute; left: 0; top: 10%; bottom: 10%;
    width: 3px; background: var(--ais-accent); border-radius: 0 2px 2px 0;
}
.ais-sb-divider { width: 32px; height: 1px; background: var(--ais-border); margin: 4px 0; }
.ais-sb-spacer { flex: 1; }
.ais-sb-avatar {
    width: 32px; height: 32px; border-radius: 50%;
    background: linear-gradient(135deg, #2a2a2a, #161616);
    display: inline-flex; align-items: center; justify-content: center;
    font-size: 13px; color: var(--ais-accent);
    margin: 0 auto 10px;
    overflow: hidden;
}
.ais-sb-avatar img { width: 100%; height: 100%; object-fit: cover; }

/* ============ Header ============ */
.ais-header {
    grid-column: 2; grid-row: 1;
    background: var(--ais-level1-bg);
    border-bottom: 1px solid var(--ais-border);
    display: flex; align-items: center;
    padding: 0 16px; gap: 12px;
}
.ais-hdr-back {
    background: transparent; border: 1px solid var(--ais-border-strong);
    color: var(--ais-text-muted);
    width: 32px; height: 32px; border-radius: var(--ais-radius-sm);
    display: inline-flex; align-items: center; justify-content: center;
    cursor: pointer;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.ais-hdr-back:hover { color: #ddd; border-color: var(--ais-text-muted); background: rgba(255,255,255,0.04); }
.ais-hdr-title {
    font-size: 14px; font-weight: 600;
    background: transparent; border: 1px solid transparent;
    color: var(--ais-text);
    padding: 6px 10px; border-radius: var(--ais-radius-sm);
    min-width: 140px;
    font-family: inherit;
    transition: border-color 0.15s, background 0.15s;
}
.ais-hdr-title:hover, .ais-hdr-title:focus {
    border-color: var(--ais-border-strong);
    background: var(--ais-level2-bg);
    outline: none;
}
.ais-hdr-saved {
    font-size: 11px; color: var(--ais-text-muted);
    padding-left: 8px;
    display: inline-flex; align-items: center; gap: 6px;
}
.ais-hdr-saved::before {
    content: ''; width: 6px; height: 6px; border-radius: 50%;
    background: var(--ais-text-dim);
}
.ais-hdr-saved.saving::before { background: var(--ais-warning); animation: ais-pulse 1.2s infinite; }
.ais-hdr-saved.saved::before  { background: var(--ais-success); }
.ais-hdr-saved.dirty::before  { background: var(--ais-warning); }
@keyframes ais-pulse {
    0%, 100% { opacity: 0.4; transform: scale(0.9); }
    50%      { opacity: 1;   transform: scale(1.15); }
}
.ais-hdr-spacer { flex: 1; }
.ais-hdr-btn {
    background: transparent; border: 1px solid var(--ais-border-strong);
    color: var(--ais-text-muted);
    padding: 6px 12px; border-radius: var(--ais-radius-sm);
    font-size: 12px; cursor: pointer;
    display: inline-flex; align-items: center; gap: 6px;
    transition: all 0.15s;
    font-family: inherit;
}
.ais-hdr-btn:hover { color: #ddd; border-color: var(--ais-text-muted); background: rgba(255,255,255,0.04); }
.ais-hdr-btn.primary {
    background: #fff; color: #000; border-color: #fff; font-weight: 600;
}
.ais-hdr-btn.primary:hover { background: #eee; }
.ais-hdr-btn.icon-only { padding: 6px; width: 32px; height: 32px; justify-content: center; }
.ais-hdr-btn i { font-size: 14px; }

.ais-proj-picker {
    display: flex; gap: 6px; align-items: center;
    padding-left: 8px; margin-left: 4px;
    border-left: 1px solid var(--ais-border);
}
.ais-proj-picker select {
    background: var(--ais-level2-bg); color: var(--ais-text);
    border: 1px solid var(--ais-border); border-radius: var(--ais-radius-sm);
    padding: 5px 8px; font-size: 11px;
    cursor: pointer; font-family: inherit;
}
.ais-proj-picker select:hover { border-color: var(--ais-border-strong); }
.ais-proj-picker select:focus { outline: none; border-color: var(--ais-accent); }

/* ============ Canvas ============ */
.ais-canvas-area {
    grid-column: 2; grid-row: 2;
    position: relative;
    background: var(--ais-level0-bg);
    overflow: hidden;
}
.ais-canvas-viewport {
    position: absolute; inset: 0;
    overflow: hidden;
    cursor: grab;
}
.ais-canvas-viewport.panning { cursor: grabbing; }
.ais-canvas-stage {
    position: absolute; left: 0; top: 0;
    width: 1px; height: 1px;
    transform-origin: 0 0;
}
.ais-canvas-grid {
    position: absolute;
    left: -50000px; top: -50000px;
    width: 100000px; height: 100000px;
    background-image: radial-gradient(circle, #1f1f1f 1px, transparent 1px);
    background-size: 20px 20px;
    pointer-events: none;
}
.ais-edges-layer {
    position: absolute;
    left: -50000px; top: -50000px;
    width: 100000px; height: 100000px;
    pointer-events: none;
}
.ais-edges-layer .ais-edge {
    fill: none; stroke: var(--ais-handle-any); stroke-width: 2;
    transition: stroke-width 0.15s, opacity 0.15s;
    pointer-events: stroke;
    cursor: pointer;
    opacity: 0.85;
}
.ais-edges-layer .ais-edge:hover { stroke-width: 3.5; opacity: 1; }
.ais-edges-layer .ais-edge.tmp { stroke-dasharray: 6 4; opacity: 0.65; pointer-events: none; }
.ais-edges-layer .ais-edge[data-type="text"]  { stroke: var(--ais-handle-text); }
.ais-edges-layer .ais-edge[data-type="image"], .ais-edges-layer .ais-edge[data-type="images"] { stroke: var(--ais-handle-image); }
.ais-edges-layer .ais-edge[data-type="video"] { stroke: var(--ais-handle-video); }
.ais-edges-layer .ais-edge[data-type="audio"] { stroke: var(--ais-handle-audio); }

.ais-canvas-empty {
    position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
    text-align: center; color: var(--ais-text-muted);
    pointer-events: none; opacity: 0.6;
}
.ais-canvas-empty-icon { font-size: 56px; margin-bottom: 12px; }
.ais-canvas-empty-title { font-size: 18px; font-weight: 600; margin-bottom: 8px; color: var(--ais-text); }
.ais-canvas-empty-hint { font-size: 12px; line-height: 1.8; }
.ais-canvas-empty kbd {
    display: inline-block; padding: 1px 6px; background: #222; border: 1px solid #333;
    border-radius: 3px; font-size: 10px; font-family: ui-monospace, monospace;
    color: var(--ais-text); margin: 0 2px;
}

/* ============ Node ============ */
.ais-node {
    position: absolute;
    background: var(--ais-level2-bg);
    border: 1px solid var(--ais-border);
    border-radius: var(--ais-radius);
    box-shadow: var(--ais-shadow-node);
    min-width: 280px;
    overflow: visible;
    transition: border-color 0.15s, box-shadow 0.15s;
    z-index: 1;
}
.ais-node:hover { border-color: var(--ais-border-strong); }
.ais-node.selected {
    border-color: var(--ais-accent);
    box-shadow: 0 0 0 1px var(--ais-accent), var(--ais-shadow-node);
    z-index: 5;
}
.ais-node.generating {
    animation: ais-node-pulse 1.6s ease-in-out infinite;
}
@keyframes ais-node-pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(244, 114, 182, 0.0), var(--ais-shadow-node); }
    50%      { box-shadow: 0 0 0 2px rgba(244, 114, 182, 0.45), var(--ais-shadow-node); }
}
.ais-node.error { border-color: var(--ais-danger); }

.ais-node-head {
    display: flex; align-items: center; gap: 8px;
    padding: 10px 12px;
    border-bottom: 1px solid var(--ais-border);
    background: var(--ais-level2-bg);
    border-radius: var(--ais-radius) var(--ais-radius) 0 0;
    cursor: grab; user-select: none;
}
.ais-node-head:active { cursor: grabbing; }
.ais-node-head-icon {
    width: 24px; height: 24px; flex-shrink: 0;
    background: var(--ais-level3-bg); border-radius: var(--ais-radius-sm);
    display: inline-flex; align-items: center; justify-content: center;
    font-size: 13px;
}
.ais-node-head-title {
    flex: 1; min-width: 0;
    font-size: 13px; font-weight: 500;
    overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
    background: transparent; border: none; color: var(--ais-text);
    font-family: inherit;
    padding: 2px 0;
}
.ais-node-head-title:focus { outline: none; }
.ais-node-head-tag {
    background: var(--ais-level3-bg);
    color: var(--ais-text-muted);
    padding: 1px 7px; border-radius: 999px;
    font-size: 9px; letter-spacing: 0.5px;
    text-transform: uppercase;
    flex-shrink: 0;
}
.ais-node-head-actions {
    display: flex; gap: 2px; flex-shrink: 0;
}
.ais-node-head-actions button {
    background: transparent; border: none;
    width: 24px; height: 24px; border-radius: 4px;
    color: var(--ais-text-muted); cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
    transition: background 0.15s, color 0.15s;
}
.ais-node-head-actions button i { font-size: 12px; }
.ais-node-head-actions button:hover { background: rgba(255,255,255,0.06); color: var(--ais-text); }
.ais-node-head-actions button.danger:hover { color: var(--ais-danger); background: rgba(248,113,113,0.12); }

.ais-node-body {
    padding: 10px 12px;
    display: flex; flex-direction: column; gap: 8px;
    position: relative;
}

.ais-node-foot {
    padding: 8px 12px;
    border-top: 1px solid var(--ais-border);
    display: flex; align-items: center; gap: 8px;
    background: rgba(0,0,0,0.18);
    border-radius: 0 0 var(--ais-radius) var(--ais-radius);
}
.ais-node-foot-spacer { flex: 1; }
.ais-unlimited {
    display: inline-flex; align-items: center; gap: 6px;
    color: var(--ais-text-muted); font-size: 10px;
    cursor: pointer; user-select: none;
}
.ais-unlimited i { font-size: 13px; }
.ais-unlimited input {
    appearance: none; -webkit-appearance: none;
    width: 26px; height: 14px;
    background: var(--ais-level3-bg); border-radius: 7px;
    position: relative; cursor: pointer;
    transition: background 0.15s;
    margin: 0;
}
.ais-unlimited input::after {
    content: ''; position: absolute; left: 2px; top: 2px;
    width: 10px; height: 10px; border-radius: 50%;
    background: #888;
    transition: left 0.15s, background 0.15s;
}
.ais-unlimited input:checked { background: var(--ais-accent-soft); }
.ais-unlimited input:checked::after { left: 14px; background: var(--ais-accent); }

.ais-node-run-btn {
    background: #fff; color: #000;
    border: none; border-radius: var(--ais-radius-sm);
    padding: 6px 14px; font-size: 12px; font-weight: 600;
    cursor: pointer;
    display: inline-flex; align-items: center; gap: 6px;
    transition: background 0.15s, transform 0.1s;
    font-family: inherit;
}
.ais-node-run-btn:hover { background: #e8e8e8; }
.ais-node-run-btn:active { transform: scale(0.97); }
.ais-node-run-btn[disabled] { opacity: 0.5; cursor: not-allowed; }

/* === content === */
.ais-node-textarea {
    width: 100%; min-height: 80px; resize: vertical;
    background: var(--ais-level3-bg); color: var(--ais-text);
    border: 1px solid var(--ais-border); border-radius: var(--ais-radius-sm);
    padding: 8px 10px; font-size: 12px;
    font-family: inherit; line-height: 1.5;
}
.ais-node-textarea:focus { outline: none; border-color: var(--ais-accent); }
.ais-node-textarea::placeholder { color: var(--ais-text-dim); }

.ais-node-row {
    display: flex; align-items: center; gap: 8px; font-size: 11px;
}
.ais-node-row label { color: var(--ais-text-muted); min-width: 50px; }
.ais-node-row select, .ais-node-row input[type="text"], .ais-node-row input[type="number"] {
    flex: 1;
    background: var(--ais-level3-bg); color: var(--ais-text);
    border: 1px solid var(--ais-border); border-radius: 4px;
    padding: 4px 8px; font-size: 11px; font-family: inherit;
}
.ais-node-row select:focus, .ais-node-row input:focus { outline: none; border-color: var(--ais-accent); }
.ais-node-params { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; }

.ais-node-chips { display: flex; flex-wrap: wrap; gap: 4px; }
.ais-node-chip {
    background: var(--ais-level3-bg); color: var(--ais-text-muted);
    border: 1px solid transparent;
    padding: 3px 9px; border-radius: 999px;
    font-size: 10px; cursor: pointer;
    transition: all 0.15s;
}
.ais-node-chip:hover { color: var(--ais-text); border-color: var(--ais-border-strong); }
.ais-node-chip.active {
    background: var(--ais-accent-soft);
    color: var(--ais-accent);
    border-color: rgba(244, 114, 182, 0.4);
}

/* media */
.ais-node-media {
    width: 100%; border-radius: var(--ais-radius-sm);
    background: var(--ais-level3-bg);
    overflow: hidden; position: relative;
    aspect-ratio: 1 / 1;
    display: flex; align-items: center; justify-content: center;
}
.ais-node-media img, .ais-node-media video {
    width: 100%; height: 100%; object-fit: contain; display: block;
}
.ais-node-media .ais-placeholder {
    color: var(--ais-text-dim); font-size: 11px; text-align: center;
    display: flex; flex-direction: column; align-items: center; gap: 6px;
}
.ais-node-media .ais-placeholder i { font-size: 22px; }

.ais-node-media-overlay {
    position: absolute; inset: 0;
    display: flex; align-items: center; justify-content: center; gap: 6px;
    background: linear-gradient(180deg, rgba(0,0,0,0.0) 0%, rgba(0,0,0,0.5) 100%);
    opacity: 0; pointer-events: none;
    transition: opacity 0.18s;
}
.ais-node-media:hover .ais-node-media-overlay { opacity: 1; pointer-events: auto; }
.ais-node-media-overlay button {
    background: rgba(20,20,20,0.85); border: 1px solid rgba(255,255,255,0.12);
    color: #fff; width: 30px; height: 30px; border-radius: var(--ais-radius-sm);
    display: inline-flex; align-items: center; justify-content: center;
    cursor: pointer; backdrop-filter: blur(6px);
    transition: background 0.15s, transform 0.1s;
}
.ais-node-media-overlay button i { font-size: 13px; }
.ais-node-media-overlay button:hover { background: rgba(40,40,40,0.95); transform: scale(1.06); }

.ais-dropzone {
    width: 100%; border: 2px dashed var(--ais-border-strong);
    border-radius: var(--ais-radius-sm);
    padding: 16px; text-align: center;
    color: var(--ais-text-muted); font-size: 11px;
    cursor: pointer;
    transition: border-color 0.15s, background 0.15s;
}
.ais-dropzone:hover { border-color: var(--ais-accent); color: var(--ais-text); }
.ais-dropzone.active { border-color: var(--ais-accent); background: var(--ais-accent-soft); }
.ais-dropzone i { font-size: 22px; display: block; margin-bottom: 4px; }

.ais-node-output { display: flex; flex-direction: column; gap: 6px; }
.ais-node-output-placeholder {
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    gap: 6px; padding: 18px;
    background: var(--ais-level3-bg); border-radius: var(--ais-radius-sm);
    color: var(--ais-text-dim); font-size: 11px;
}
.ais-spinner {
    width: 20px; height: 20px;
    border: 2px solid var(--ais-border-strong); border-top-color: var(--ais-accent);
    border-radius: 50%; animation: ais-spin 0.8s linear infinite;
}
@keyframes ais-spin { to { transform: rotate(360deg); } }
.ais-node-error {
    background: rgba(248,113,113,0.1); color: var(--ais-danger);
    padding: 6px 10px; border-radius: var(--ais-radius-sm);
    font-size: 11px; line-height: 1.5;
    border-left: 3px solid var(--ais-danger);
}
.ais-node-images { display: grid; grid-template-columns: repeat(2, 1fr); gap: 4px; }
.ais-node-images img {
    width: 100%; aspect-ratio: 1 / 1; object-fit: cover;
    border-radius: var(--ais-radius-sm); cursor: pointer;
    transition: transform 0.15s;
}
.ais-node-images img:hover { transform: scale(1.02); }

/* exec history bar */
.ais-node-exec-history {
    display: flex; align-items: center; justify-content: space-between;
    padding: 6px 12px;
    border-top: 1px solid var(--ais-border);
    background: rgba(0,0,0,0.18);
    font-size: 10px; color: var(--ais-text-muted);
}
.ais-node-exec-history button {
    background: transparent; border: none;
    width: 20px; height: 20px; border-radius: 4px;
    color: var(--ais-text-muted); cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
    transition: background 0.15s, color 0.15s;
}
.ais-node-exec-history button i { font-size: 11px; }
.ais-node-exec-history button:hover:not(:disabled) { background: rgba(255,255,255,0.06); color: var(--ais-text); }
.ais-node-exec-history button:disabled { opacity: 0.3; cursor: default; }
.ais-node-exec-history .ais-exec-pos { font-variant-numeric: tabular-nums; }

/* === handle / port === */
.ais-port {
    position: absolute;
    width: 12px; height: 12px;
    border-radius: 50%;
    background: var(--ais-level1-bg);
    border: 2px solid var(--ais-handle-any);
    cursor: crosshair;
    transition: transform 0.15s, background 0.15s;
}
.ais-port:hover { transform: scale(1.4); }
.ais-port.input  { left: -6px; }
.ais-port.output { right: -6px; }
.ais-port.connected { background: var(--ais-handle-any); }
.ais-port[data-port-type="text"]  { border-color: var(--ais-handle-text); }
.ais-port[data-port-type="text"].connected { background: var(--ais-handle-text); }
.ais-port[data-port-type="image"], .ais-port[data-port-type="images"]  { border-color: var(--ais-handle-image); }
.ais-port[data-port-type="image"].connected, .ais-port[data-port-type="images"].connected { background: var(--ais-handle-image); }
.ais-port[data-port-type="video"] { border-color: var(--ais-handle-video); }
.ais-port[data-port-type="video"].connected { background: var(--ais-handle-video); }
.ais-port[data-port-type="audio"] { border-color: var(--ais-handle-audio); }
.ais-port[data-port-type="audio"].connected { background: var(--ais-handle-audio); }

.ais-port-label {
    position: absolute;
    font-size: 9px; color: var(--ais-text-muted);
    pointer-events: none; white-space: nowrap;
    opacity: 0;
    transition: opacity 0.18s;
}
.ais-port-label.input  { left: 14px; }
.ais-port-label.output { right: 14px; text-align: right; }
.ais-node:hover .ais-port-label { opacity: 1; }
.ais-port-label[data-port-type="text"]  { color: var(--ais-handle-text); }
.ais-port-label[data-port-type="image"], .ais-port-label[data-port-type="images"]  { color: var(--ais-handle-image); }
.ais-port-label[data-port-type="video"] { color: var(--ais-handle-video); }
.ais-port-label[data-port-type="audio"] { color: var(--ais-handle-audio); }

/* ============ floating toolbar ============ */
.ais-floating-toolbar {
    position: absolute;
    bottom: 16px; left: 50%; transform: translateX(-50%);
    display: flex; align-items: center; gap: 2px;
    background: var(--ais-level1-bg);
    border: 1px solid var(--ais-border);
    border-radius: 999px;
    padding: 4px 6px;
    box-shadow: var(--ais-shadow-lg);
    z-index: 50;
}
.ais-ft-btn {
    background: transparent; border: none;
    width: 32px; height: 32px; border-radius: 50%;
    color: var(--ais-text-muted); cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
    transition: background 0.15s, color 0.15s;
    font-family: inherit;
}
.ais-ft-btn i { font-size: 13px; }
.ais-ft-btn:hover { background: rgba(255,255,255,0.06); color: var(--ais-text); }
.ais-ft-btn[data-active="true"] { background: var(--ais-accent-soft); color: var(--ais-accent); }
.ais-ft-btn:disabled { opacity: 0.3; cursor: default; }
.ais-ft-divider { width: 1px; height: 18px; background: var(--ais-border); margin: 0 4px; }
.ais-ft-zoom-value {
    font-size: 10px; color: var(--ais-text-muted);
    padding: 0 6px; font-variant-numeric: tabular-nums;
    min-width: 40px; text-align: center;
}

/* minimap */
.ais-minimap {
    position: absolute;
    bottom: 16px; right: 16px;
    width: 180px; height: 120px;
    background: var(--ais-level1-bg);
    border: 1px solid var(--ais-border);
    border-radius: var(--ais-radius-sm);
    overflow: hidden;
    box-shadow: var(--ais-shadow-lg);
    z-index: 40;
}
.ais-minimap-canvas { display: block; width: 100%; height: 100%; }
.ais-minimap-viewport {
    position: absolute; pointer-events: none;
    border: 1px solid var(--ais-accent);
    background: rgba(244,114,182,0.06);
}

/* ============ Right-click menu ============ */
.ais-context-menu {
    position: fixed;
    background: var(--ais-level1-bg);
    border: 1px solid var(--ais-border);
    border-radius: var(--ais-radius-sm);
    box-shadow: var(--ais-shadow-lg);
    padding: 4px;
    min-width: 200px;
    z-index: 9999;
    display: none;
}
.ais-context-menu.show { display: block; }
.ais-context-menu-item {
    display: flex; align-items: center; gap: 8px;
    padding: 6px 10px; font-size: 12px;
    color: var(--ais-text); cursor: pointer;
    border-radius: 4px;
    transition: background 0.1s;
}
.ais-context-menu-item:hover { background: var(--ais-accent-soft); color: var(--ais-accent); }
.ais-context-menu-item i { font-size: 13px; width: 16px; }
.ais-context-menu-item.danger:hover { background: rgba(248,113,113,0.15); color: var(--ais-danger); }
.ais-context-menu-divider { height: 1px; background: var(--ais-border); margin: 4px 0; }

/* ============ Lightbox ============ */
.ais-lightbox {
    position: fixed; inset: 0;
    background: rgba(0,0,0,0.92);
    z-index: 10000;
    display: none;
    align-items: center; justify-content: center;
    padding: 20px;
}
.ais-lightbox.open { display: flex; }
.ais-lightbox-content {
    max-width: 96vw; max-height: 92vh;
    position: relative;
    display: flex; flex-direction: column; align-items: center; gap: 12px;
}
.ais-lightbox-content img, .ais-lightbox-content video {
    max-width: 100%; max-height: 78vh;
    border-radius: var(--ais-radius-sm);
}
.ais-lightbox-close {
    position: absolute; top: -36px; right: 0;
    background: transparent; border: 1px solid #444; color: #ccc;
    width: 32px; height: 32px; border-radius: 50%;
    cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
}
.ais-lightbox-meta { color: #888; font-size: 11px; display: flex; gap: 16px; }
.ais-lightbox-actions { display: flex; gap: 8px; }
.ais-lightbox-actions button {
    background: rgba(255,255,255,0.08); color: #fff;
    border: 1px solid rgba(255,255,255,0.2); border-radius: var(--ais-radius-sm);
    padding: 6px 14px; cursor: pointer; font-size: 12px;
    font-family: inherit;
    transition: background 0.15s;
}
.ais-lightbox-actions button:hover { background: rgba(255,255,255,0.16); }

/* ============ Toast ============ */
.ais-toast {
    position: fixed; bottom: 70px; left: 50%; transform: translateX(-50%);
    background: var(--ais-level1-bg); color: var(--ais-text);
    border: 1px solid var(--ais-border); border-radius: var(--ais-radius-sm);
    padding: 10px 18px;
    box-shadow: var(--ais-shadow-lg);
    font-size: 12px;
    z-index: 100000;
    opacity: 1;
    transition: opacity 0.3s;
}
.ais-toast.success { border-left: 3px solid var(--ais-success); }
.ais-toast.error   { border-left: 3px solid var(--ais-danger); }
.ais-toast.warning { border-left: 3px solid var(--ais-warning); }
.ais-toast.info    { border-left: 3px solid var(--ais-accent); }

/* ============ Popovers (workflow list / add node palette) ============ */
.ais-popover {
    position: absolute;
    background: var(--ais-level1-bg);
    border: 1px solid var(--ais-border);
    border-radius: var(--ais-radius);
    box-shadow: var(--ais-shadow-lg);
    padding: 8px;
    z-index: 80;
    display: none;
    min-width: 240px;
}
.ais-popover.show { display: block; }
.ais-popover-title {
    font-size: 10px; text-transform: uppercase; letter-spacing: 1px;
    color: var(--ais-text-dim); padding: 4px 6px 6px;
    display: flex; justify-content: space-between; align-items: center;
}
.ais-popover-title button {
    background: transparent; border: none; color: var(--ais-accent);
    cursor: pointer; font-size: 14px;
}
.ais-flow-search {
    width: 100%; padding: 6px 10px; font-size: 12px;
    background: var(--ais-level2-bg); border: 1px solid var(--ais-border);
    border-radius: var(--ais-radius-sm); color: var(--ais-text);
    margin-bottom: 8px; font-family: inherit;
}
.ais-flow-search:focus { outline: none; border-color: var(--ais-accent); }
.ais-flow-list { display: flex; flex-direction: column; gap: 2px; max-height: 320px; overflow-y: auto; }
.ais-flow-item {
    padding: 8px 10px; border-radius: var(--ais-radius-sm);
    cursor: pointer; font-size: 12px;
    display: flex; justify-content: space-between; align-items: center;
    transition: background 0.1s;
}
.ais-flow-item:hover { background: rgba(255,255,255,0.04); }
.ais-flow-item.active { background: var(--ais-accent-soft); color: var(--ais-accent); }
.ais-flow-empty { padding: 20px; text-align: center; color: var(--ais-text-dim); font-size: 11px; }

.ais-palette-group { margin-bottom: 10px; }
.ais-palette-group:last-child { margin-bottom: 0; }
.ais-palette-group-title {
    font-size: 10px; text-transform: uppercase; letter-spacing: 1px;
    color: var(--ais-text-dim); padding: 4px 6px 6px;
}
.ais-palette-chip {
    display: flex; align-items: center; gap: 8px;
    padding: 7px 8px;
    cursor: grab; border-radius: var(--ais-radius-sm);
    font-size: 12px; color: var(--ais-text);
    transition: background 0.1s;
    user-select: none;
}
.ais-palette-chip:hover { background: rgba(255,255,255,0.05); }
.ais-palette-chip:active { cursor: grabbing; }
.ais-palette-chip i { color: var(--ais-accent); font-size: 14px; width: 18px; }

/* ============ Small screen blocker ============ */
.ais-small-blocker {
    display: none;
    position: fixed; inset: 0;
    background: var(--ais-level0-bg);
    z-index: 99999;
    align-items: center; justify-content: center;
    text-align: center;
    padding: 32px;
    flex-direction: column;
}
@media (max-width: 900px) {
    .ais-small-blocker { display: flex; }
    .ais-shell { display: none; }
}
.ais-small-blocker i { font-size: 36px; color: var(--ais-text-muted); margin-bottom: 12px; }
.ais-small-blocker h3 { font-size: 16px; margin: 0 0 8px; }
.ais-small-blocker p { font-size: 13px; color: var(--ais-text-muted); max-width: 320px; margin: 0 auto 16px; line-height: 1.6; }
.ais-small-blocker a {
    color: var(--ais-accent); text-decoration: none;
    padding: 8px 16px; border: 1px solid var(--ais-accent);
    border-radius: var(--ais-radius-sm); display: inline-block;
    font-size: 12px;
}

/* ============ reduced motion ============ */
@media (prefers-reduced-motion: reduce) {
    .ais-node, .ais-node.generating, .ais-edge, .ais-spinner,
    .ais-hdr-saved::before, .ais-node-media-overlay {
        animation: none !important;
        transition: none !important;
    }
}