/* fa-page.css — Function Analysis page (shown in place of the semantic
   graph inside #graph-viewport). Palette matches the graph panel / charts. */

.fa-hidden { display: none !important; }

/* ── ƒ button on graph nodes — hover-revealed, matching the chart button
      (see .d3sg-chart-btn in sg-chart.css) ── */
.d3sg-fa-btn {
    opacity: 0;
    cursor: pointer;
    pointer-events: all;
    transition: opacity 0.12s ease-out;
}
.d3sg-node:hover .d3sg-fa-btn {
    opacity: 0.7;
}
.d3sg-fa-btn:hover {
    opacity: 1 !important;
}

#fa-page-container {
    display: none;
    position: absolute;
    inset: 0;
    overflow-y: auto;
    padding: 0 20px 24px;
    background: #0a0c1a;
    z-index: 15;
}
#fa-page-container.open { display: block; }

.fa-card {
    background: #10142a;
    border: 1px solid rgba(110, 124, 180, 0.35);
    border-radius: 10px;
    padding: 12px 16px;
    margin-bottom: 12px;
    color: #dde6ff;
    font-size: 13.5px;
}

/* ── header — sticky so the title stays visible while scrolling ── */
.fa-header {
    position: sticky;
    top: 0;
    z-index: 20;
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 0 10px;
    margin-bottom: 12px;
    background: #0a0c1a;
    border-bottom: 1px solid rgba(110, 124, 180, 0.18);
    flex-wrap: wrap;
}
.fa-title { font-size: 16px; font-weight: 600; color: #dde6ff; }
.fa-expr { font-size: 15px; color: #aebbd1; }
.fa-btn {
    background: none;
    border: 1px solid rgba(110, 124, 180, 0.35);
    color: #8fa8c8;
    border-radius: 6px;
    padding: 2px 10px;
    font-size: 12.5px;
    cursor: pointer;
}
.fa-btn:hover { color: #dde6ff; border-color: #42a5f5; background: rgba(66, 165, 245, 0.1); }
.fa-back { font-size: 15px; padding: 2px 12px; }
.fa-json-btn { margin-left: auto; display: inline-flex; align-items: center; padding: 3px 8px; }
.fa-json-btn svg { display: block; }
.fa-delete-btn { display: inline-flex; align-items: center; padding: 3px 8px; }
.fa-delete-btn svg { display: block; }
.fa-delete-btn:hover { color: #ef9a9a; border-color: #ef5350; background: rgba(239, 83, 80, 0.1); }
/* When the JSON button is absent (loading/error), the delete button is the
   one that must push to the right edge. */
.fa-header > .fa-delete-btn:nth-child(4) { margin-left: auto; }
.fa-json-btn.open { background: rgba(66, 165, 245, 0.15); color: #dde6ff; }

/* ── status / error ── */
.fa-status { display: flex; align-items: center; gap: 10px; color: #8fa8c8; }
.fa-status-label { display: inline-flex; align-items: center; gap: 5px; }
.fa-error { color: #ef9a9a; display: flex; align-items: center; gap: 14px; }
.fa-retry { color: #dde6ff; }
.fa-abstain { color: #8fa8c8; font-style: italic; }

/* ── story ── */
.fa-story { color: #aebbd1; }
/* AI-authorship marker — the shared robot icon in the chat-avatar tint. */
.fa-ai-badge {
    display: inline-block;
    color: #cdd3f5;             /* same tint as the chat's .msg-avatar */
    opacity: 0.9;
    margin-right: 2px;
}
.fa-ai-badge svg { vertical-align: -2px; }

/* ── views ── */
.fa-view-tabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 6px; }
.fa-view-tab.active {
    background: rgba(66, 165, 245, 0.15);
    color: #dde6ff;
    border-color: #42a5f5;
}
.fa-view-rationale {
    color: #7e8aa3;
    font-size: 12px;
    font-style: italic;
    margin: 2px 0 8px;
    min-height: 16px;
}
.fa-view-actions { margin-left: auto; display: flex; gap: 6px; }
.fa-expr-btn { font-family: Georgia, serif; font-style: italic; }
.fa-expr-btn.open { background: rgba(66, 165, 245, 0.15); color: #dde6ff; border-color: #42a5f5; }

/* what each curve plots: colour swatch, label, LaTeX, evaluated script */
.fa-expr-panel { display: none; margin-top: 10px; }
.fa-expr-panel.open { display: block; }
.fa-expr-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 4px 0;
    border-top: 1px solid rgba(110, 124, 180, 0.12);
    font-size: 12.5px;
}
.fa-expr-row:first-child { border-top: none; }
.fa-expr-swatch { width: 10px; height: 3px; border-radius: 2px; flex-shrink: 0; }
.fa-expr-swatch-ann { background: rgba(239, 83, 80, 0.75); height: 0; border-top: 2px dashed rgba(239, 83, 80, 0.75); }
.fa-expr-label { color: #8fa8c8; min-width: 92px; }
.fa-expr-math { color: #dde6ff; }
.fa-expr-code {
    margin-left: auto;
    font: 11.5px ui-monospace, Menlo, monospace;
    color: #7e8aa3;
    background: rgba(110, 124, 180, 0.1);
    border-radius: 4px;
    padding: 1px 7px;
    max-width: 48%;
    overflow-x: auto;
    white-space: nowrap;
}

/* the CAS report, one row per detected feature */
.fa-feat-btn { font-size: 12px; }
.fa-feat-btn.open { background: rgba(66, 165, 245, 0.15); color: #dde6ff; border-color: #42a5f5; }
.fa-feat-panel { display: none; margin-top: 10px; }
.fa-feat-panel.open { display: block; }
.fa-feat-row {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 4px 0;
    border-top: 1px solid rgba(110, 124, 180, 0.12);
    font-size: 12.5px;
}
.fa-feat-row:first-child { border-top: none; }
.fa-feat-label { color: #8fa8c8; min-width: 118px; }
.fa-feat-math { color: #dde6ff; }
.fa-feat-detail { color: #aebbd1; }
.fa-feat-note { color: #7e8aa3; font-style: italic; font-size: 11.5px; }
/* a CAS timeout, said plainly — unknown is not the same as absent */
.fa-feat-stalled { color: #ffcc80; font-style: italic; font-size: 11.5px; }
/* why a detected point has no dot on the curve */
.fa-feat-off {
    margin-left: auto;
    color: #7e8aa3;
    font-size: 11px;
    border: 1px solid rgba(110, 124, 180, 0.25);
    border-radius: 4px;
    padding: 0 6px;
}

.fa-ann-legend { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; margin-bottom: 6px; }
.fa-ann-chip { font-size: 11px; border-style: dashed; }
/* which curve is which — HTML (not the Chart.js canvas legend) so the
   labels can render as KaTeX; see _renderSeriesLegend */
.fa-series-key {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 11px;
    color: #aebbd1;
    padding: 2px 9px;
}
.fa-series-key.off { opacity: 0.45; text-decoration: line-through; }
.fa-series-key .katex { font-size: 1.05em; }
/* the curve's own stroke: solid for the analyzed expression, dashed for a
   companion plot (colour is set inline from the dataset) */
.fa-series-swatch {
    width: 15px;
    height: 0;
    border-top: 2px solid currentColor;
    flex-shrink: 0;
}
.fa-series-swatch.dashed { border-top-style: dashed; }
/* what the drawn markers mean */
.fa-mark-key {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 11px;
    color: #7e8aa3;
    padding: 2px 9px;
}
.fa-mark-key.off { opacity: 0.45; text-decoration: line-through; }
.fa-key-glyph { display: inline-block; width: 8px; height: 8px; border-radius: 50%; }
.fa-key-zero { background: #dde6ff; }
.fa-key-extremum { background: #ffa726; }
.fa-key-sing {
    width: 0;
    height: 10px;
    border-radius: 0;
    border-left: 2px dashed rgba(239, 83, 80, 0.75);
}
.fa-ann-chip.off { opacity: 0.4; text-decoration: line-through; }
.fa-canvas-wrap { position: relative; height: 320px; }
.fa-canvas-wrap canvas { width: 100% !important; height: 100% !important; }

/* Axis titles — HTML so they render as KaTeX. The descendant selector keeps
   these absolutely positioned even though .fa-askable (added by the hover ask
   button, and declared later) sets position: relative. */
.fa-canvas-wrap .fa-axis-title {
    position: absolute;
    color: #8fa8c8;
    font-size: 12px;
    pointer-events: auto;
}
/* The y-title is rotated; counter-rotate its ask button so it stays upright. */
.fa-axis-y .fa-hover-ask { transform: rotate(90deg); transform-origin: center; }
.fa-axis-x { left: 50%; bottom: -2px; transform: translateX(-50%); }
/* Rotated about its own centre, which sits ~half a line-height in from the
   left edge so the whole label lands inside the canvas instead of being
   clipped. Chart.js reserves the matching space via layout.padding.left. */
.fa-axis-y {
    left: 11px;
    top: 50%;
    transform: translate(-50%, -50%) rotate(-90deg);
    transform-origin: center center;
    max-width: 240px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* HTML hover tooltip (canvas tooltips can't render math) */
.fa-chart-tip {
    position: absolute;
    z-index: 25;
    display: none;
    transform: translate(-50%, calc(-100% - 12px));
    /* 70% transparent, so the curve the learner is reading stays visible
       underneath. The PANEL is see-through, not its contents — fading the
       text along with it would cost more legibility than the glimpse of
       chart is worth. The blur keeps grid lines from running through the
       numbers. */
    background: rgba(10, 12, 26, 0.3);
    backdrop-filter: blur(3px);
    -webkit-backdrop-filter: blur(3px);
    border: 1px solid rgba(110, 124, 180, 0.45);
    border-radius: 7px;
    padding: 6px 9px;
    font-size: 12px;
    color: #aebbd1;
    /* Transparent to the pointer while it is just a hover readout, so the
       click that pins it reaches the canvas underneath rather than being
       swallowed by the very box it is meant to pin. */
    pointer-events: none;
    white-space: nowrap;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.4);
}
.fa-chart-tip.show { display: block; }
/* Pinned: parked where the learner dropped it, no longer following the
   pointer. `transform: none` is what makes left/top plain drag coordinates. */
.fa-chart-tip.pinned {
    transform: none;
    /* Now it IS interactive: it can be dragged, and it swallows its own
       clicks so clicking the note never counts as clicking the chart. */
    pointer-events: auto;
    cursor: move;
    border-color: rgba(66, 165, 245, 0.75);
    box-shadow: 0 4px 18px rgba(0, 0, 0, 0.55);
}
.fa-tip-head {
    display: flex;
    align-items: center;
    gap: 12px;                  /* keeps the ask button off the readout */
    color: #dde6ff;
    margin-bottom: 3px;
}
/* Top-right corner of a pinned note. This is the shared .ai-ask-btn circle,
   untouched — no size, padding or geometry of its own, or it stops matching
   every other ask button in the app. It is revealed by hovering the note,
   the same as every other hover-revealed ask; only the corner placement is
   its own. */
.fa-tip-ask {
    margin-left: auto;
    pointer-events: none;       /* same as .fa-askable's hidden state */
    transition: opacity 0.12s ease;
}
.fa-chart-tip.pinned:hover .fa-tip-ask { opacity: 1; pointer-events: auto; }
.fa-tip-row { display: flex; align-items: center; gap: 6px; }
.fa-tip-swatch { width: 9px; height: 3px; border-radius: 2px; flex-shrink: 0; }
.fa-tip-name { max-width: 210px; overflow: hidden; text-overflow: ellipsis; }
.fa-tip-val { margin-left: auto; color: #dde6ff; font: 11.5px ui-monospace, Menlo, monospace; }

/* Why a y-axis click could not be answered — brief, and out of the way. */
.fa-snap-miss {
    position: absolute;
    left: 50%;
    bottom: 8px;
    transform: translateX(-50%);
    max-width: 92%;
    padding: 4px 11px;
    border-radius: 6px;
    background: rgba(10, 12, 26, 0.92);
    border: 1px solid rgba(239, 83, 80, 0.45);
    color: #dde6ff;
    font-size: 11.5px;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.15s ease;
}
.fa-snap-miss.show { opacity: 1; }

/* KaTeX layer for annotation labels (canvas text can't render math) */
.fa-chart-labels { position: absolute; inset: 0; pointer-events: none; }
.fa-chart-label {
    position: absolute;
    font-size: 11px;
    line-height: 1.2;
    color: #ef9a9a;
    white-space: nowrap;
    text-shadow: 0 0 4px #0a0c1a, 0 0 4px #0a0c1a;
}
.fa-chart-label.band { color: #8fa8c8; }
/* Annotations are hoverable: they report the values at their marker. */
.fa-chart-label.probe { pointer-events: auto; cursor: help; }
.fa-chart-label.probe:hover { color: #dde6ff; }
.fa-chart-label .katex { font-size: 1em; }

/* ── sliders ── */
.fa-sliders { display: flex; gap: 22px; flex-wrap: wrap; margin-top: 10px; }
.fa-slider-row { display: flex; align-items: center; gap: 8px; font-size: 13px; }
.fa-var { color: #ffa726; min-width: 18px; text-align: center; position: relative; }
.fa-var .fa-var-ask {
    position: absolute;
    top: -13px;
    right: -15px;
    margin-left: 0;
}
.fa-slider-row input[type="range"] { width: 130px; accent-color: #42a5f5; cursor: pointer; }
.fa-slider-row input[type="range"]:active { cursor: grabbing; }
.fa-slider-val {
    font: 11.5px ui-monospace, Menlo, monospace;
    color: #8fa8c8;
    min-width: 48px;
}

/* ── quiz ── */
.fa-sect-label {
    font-size: 11px;
    letter-spacing: 0.08em;
    color: #7e8aa3;
    text-transform: uppercase;
    margin-bottom: 8px;
}
.fa-probe { border-top: 1px solid rgba(110, 124, 180, 0.12); padding: 10px 0; }
.fa-probe:first-child { border-top: none; }
.fa-probe-q { margin-bottom: 8px; }
.fa-probe-opts { display: flex; gap: 8px; flex-wrap: wrap; }
.fa-probe-chip {
    background: rgba(66, 165, 245, 0.1);
    border: 1px solid rgba(66, 165, 245, 0.45);
    color: #dde6ff;
    border-radius: 16px;
    padding: 3px 14px;
    font-size: 13px;
}
.fa-probe-chip:disabled { opacity: 0.55; cursor: default; }
.fa-probe-chip.right { background: rgba(102, 187, 106, 0.25); border-color: #66bb6a; opacity: 1; }
.fa-probe-chip.wrong { background: rgba(239, 83, 80, 0.25); border-color: #ef5350; opacity: 1; }
.fa-probe-exp { display: none; margin-top: 8px; font-size: 12.5px; color: #8fa8c8; }
.fa-probe-exp.show { display: block; }
.fa-more { margin-top: 10px; border-style: dashed; border-radius: 16px; }
.fa-more-status { margin-left: 10px; color: #7e8aa3; font-size: 12px; }

/* ── raw JSON popup ── */
.fa-json-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(4, 6, 14, 0.6);
    z-index: 60;
    align-items: center;
    justify-content: center;
}
.fa-json-overlay.open { display: flex; }
.fa-json-modal {
    background: #10142a;
    border: 1px solid rgba(110, 124, 180, 0.45);
    border-radius: 10px;
    width: min(720px, 86vw);
    max-height: 80vh;
    display: flex;
    flex-direction: column;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
}
.fa-json-modal-head {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    border-bottom: 1px solid rgba(110, 124, 180, 0.25);
    color: #aebbd1;
    font-size: 12.5px;
}
.fa-json-modal-head span { flex: 1; }
.fa-json-close { font-size: 15px; line-height: 1; padding: 1px 8px; }
.fa-json-modal pre {
    margin: 0;
    padding: 12px 14px;
    overflow: auto;
    font: 11.5px/1.45 ui-monospace, Menlo, monospace;
    color: #8fa8c8;
    white-space: pre;
}

/* ── variable description tooltip (instant, styled, KaTeX-capable) ── */
.fa-tooltip {
    display: none;
    position: absolute;
    z-index: 40;
    max-width: 320px;
    background: #060814;
    border: 1px solid rgba(110, 124, 180, 0.45);
    border-radius: 8px;
    padding: 8px 10px;
    font-size: 12.5px;
    color: #aebbd1;
    transform: translateY(-100%);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.45);
    pointer-events: none;
}
.fa-tooltip.show { display: block; }

/* ── hover-revealed AI ask button (app-wide sparkle pattern) ── */
.fa-askable { position: relative; }
.fa-askable .fa-hover-ask {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.12s ease;
    margin-left: 6px;
    vertical-align: middle;
}
.fa-askable:hover .fa-hover-ask { opacity: 1; pointer-events: auto; }

/* ── Math tab tree: artifact rows under steps ── */
.gp-tree-fa {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 2px 8px 2px 34px;
    font-size: 12px;
    color: #8fa8c8;
    cursor: pointer;
    border-left: 3px solid transparent;
}
.gp-tree-fa:hover { background: rgba(66, 165, 245, 0.08); color: #dde6ff; }
.gp-tree-fa.active {
    background: rgba(66, 165, 245, 0.12);
    border-left-color: #42a5f5;
    color: #dde6ff;
}
.gp-tree-fa .fa-glyph { color: #ffa726; font-style: italic; font-family: Georgia, serif; }
.gp-tree-fa .fa-loading { color: #7e8aa3; font-style: italic; }
.gp-tree-fa .fa-err { color: #ef9a9a; }