/*
 * decision-tree-model-selection.css — page styles for the DT model-selection lab.
 *
 * Three charts: scatter+regions, validation curve, grid-search heatmap.
 * Lots of controls (5 sliders, 4 selects, 5 preset buttons, kfold + cost knobs).
 * Local prefix: .dt-*  (mirrors the other ml/ page patterns).
 */

/* ── Canvas wrappers ────────────────────────────────────────── */
.dt-canvas-wrap {
    position: relative;
    background: var(--ms-panel-bg);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius);
    padding: 1rem;
    box-shadow: var(--ms-shadow-sm);
    margin-bottom: 0.85rem;
}
.dt-canvas-label {
    font: 500 0.72rem var(--ms-font-mono);
    color: var(--ms-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 0.45rem;
    display: flex; justify-content: space-between; align-items: center;
}
.dt-canvas-area {
    position: relative;
    width: 100%;
}
.dt-canvas-area.is-main    { height: 360px; }
.dt-canvas-area.is-medium  { height: 240px; }
.dt-canvas-area canvas {
    display: block;
    width: 100% !important;
    height: 100% !important;
    background: var(--ms-panel-bg-soft);
    border-radius: var(--ms-radius-sm);
}
#dtCanvas { cursor: crosshair; }
.dt-canvas-footer {
    font: italic 0.78rem var(--ms-font-sans);
    color: var(--ms-muted);
    margin-top: 0.55rem;
}

.dt-legend {
    display: flex; gap: 0.85rem; flex-wrap: wrap;
    font: 500 0.78rem var(--ms-font-sans);
    color: var(--ms-ink-soft);
    margin-top: 0.55rem;
}
.dt-legend-dot {
    display: inline-block; width: 10px; height: 10px;
    border-radius: 50%; margin-right: 0.3rem; vertical-align: middle;
}
.dt-legend-dot.dt-c0 { background: #ef4444; }
.dt-legend-dot.dt-c1 { background: #22c55e; }

.dt-class-indicator {
    display: inline-flex; align-items: center; gap: 0.45rem;
    padding: 0.35rem 0.75rem;
    background: var(--ms-panel-bg);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-pill);
    font: 500 0.82rem var(--ms-font-sans);
    color: var(--ms-ink);
    cursor: pointer; user-select: none;
}
.dt-class-indicator:hover { border-color: var(--ms-accent); }
.dt-class-indicator-dot {
    width: 12px; height: 12px; border-radius: 50%;
}
.dt-class-indicator[data-class="0"] .dt-class-indicator-dot { background: #ef4444; }
.dt-class-indicator[data-class="1"] .dt-class-indicator-dot { background: #22c55e; }
.dt-class-indicator-hint {
    font: 500 0.7rem var(--ms-font-mono);
    color: var(--ms-muted);
    margin-left: 0.25rem;
}

/* ── Two-column layout: charts (left) + controls (right) ───── */
.dt-layout {
    display: grid;
    grid-template-columns: 1.6fr 1fr;
    gap: 1rem;
    align-items: flex-start;
}
@media (max-width: 1080px) {
    .dt-layout { grid-template-columns: 1fr; }
}

/* ── Control groups ────────────────────────────────────────── */
.dt-control-group {
    margin-bottom: 1.1rem;
}
.dt-control-group:last-child { margin-bottom: 0; }
.dt-control-group-head {
    display: flex; align-items: baseline; gap: 0.45rem;
    margin-bottom: 0.5rem;
    font: 500 0.75rem var(--ms-font-mono);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}
.dt-control-group-head .dt-cgh-label { color: var(--ms-accent); }
.dt-control-group-head .dt-cgh-desc {
    text-transform: none; letter-spacing: 0;
    font: italic 0.78rem var(--ms-font-sans);
    color: var(--ms-muted);
}
.dt-control {
    display: flex; flex-direction: column; gap: 0.3rem;
    margin-bottom: 0.6rem;
}
.dt-control:last-child { margin-bottom: 0; }
.dt-control-label {
    display: flex; justify-content: space-between; align-items: baseline;
    font: 500 0.78rem var(--ms-font-sans);
    color: var(--ms-ink-soft);
}
.dt-control-value {
    font: 500 0.76rem var(--ms-font-mono);
    color: var(--ms-accent);
}
.dt-control input[type="range"] {
    width: 100%;
    appearance: none;
    height: 4px;
    background: var(--ms-accent-soft);
    border-radius: var(--ms-radius-pill);
    cursor: pointer;
}
.dt-control input[type="range"]::-webkit-slider-thumb {
    appearance: none; width: 16px; height: 16px;
    background: var(--ms-accent); border-radius: 50%; cursor: pointer;
}
.dt-control input[type="range"]::-moz-range-thumb {
    width: 16px; height: 16px; background: var(--ms-accent);
    border-radius: 50%; border: none;
}
.dt-control select,
.dt-control input[type="number"] {
    padding: 0.4rem 0.6rem;
    font: 500 0.84rem var(--ms-font-sans);
    color: var(--ms-ink);
    background: var(--ms-panel-bg-soft);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-sm);
    outline: none;
}
.dt-control select:focus,
.dt-control input[type="number"]:focus {
    border-color: var(--ms-accent);
    box-shadow: var(--ms-ring);
}
.dt-control-checkbox {
    display: inline-flex; align-items: center; gap: 0.4rem;
    font: 500 0.82rem var(--ms-font-sans);
    color: var(--ms-ink-soft);
    cursor: pointer;
}
.dt-control-checkbox input { accent-color: var(--ms-accent); width: 16px; height: 16px; }

.dt-preset-row {
    display: flex; gap: 0.4rem; flex-wrap: wrap;
    margin-top: 0.4rem;
}
.dt-preset {
    padding: 0.3rem 0.7rem;
    font: 500 0.78rem var(--ms-font-sans);
    background: var(--ms-panel-bg);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-pill);
    cursor: pointer;
    color: var(--ms-ink-soft);
}
.dt-preset:hover { border-color: var(--ms-accent); color: var(--ms-accent); }
.dt-preset.is-active {
    background: var(--ms-accent-soft);
    border-color: var(--ms-accent);
    color: var(--ms-accent);
}

.dt-actions {
    display: flex; gap: 0.5rem; flex-wrap: wrap;
    margin-top: 0.65rem;
}
.dt-btn {
    display: inline-flex; align-items: center; gap: 0.4rem;
    padding: 0.5rem 0.95rem;
    font: 500 0.82rem var(--ms-font-sans);
    border-radius: var(--ms-radius-sm);
    border: 1px solid var(--ms-line);
    background: var(--ms-panel-bg);
    color: var(--ms-ink);
    cursor: pointer;
    transition: transform var(--ms-transition), box-shadow var(--ms-transition);
}
.dt-btn:hover { transform: translateY(-1px); box-shadow: var(--ms-shadow-sm); }
.dt-btn.is-primary {
    background: linear-gradient(135deg, var(--ms-cta-start), var(--ms-cta-end));
    color: #fff;
    border-color: transparent;
}
.dt-btn.is-warn {
    background: var(--ms-panel-bg-soft);
    color: #b91c1c;
    border-color: rgba(239, 68, 68, 0.35);
}

/* ── Metrics readout ───────────────────────────────────────── */
.dt-metrics {
    padding: 0.85rem 1rem;
    background: var(--ms-panel-bg-soft);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-sm);
    font: 500 0.85rem var(--ms-font-sans);
    color: var(--ms-ink-soft);
}
.dt-metrics-row {
    display: flex; justify-content: space-between;
    padding: 0.2rem 0;
}
.dt-metrics-row strong {
    font: 600 0.9rem var(--ms-font-mono);
    color: var(--ms-ink);
}

/* ── Math + try-this + chip strips ─────────────────────────── */
.dt-math {
    display: grid; grid-template-columns: 1fr; gap: 0.75rem;
}
.dt-math-step {
    padding: 0.85rem 1rem;
    background: var(--ms-panel-bg-soft);
    border-left: 3px solid var(--ms-accent);
    border-radius: var(--ms-radius-sm);
}
.dt-math-step h4 {
    font: 500 0.85rem var(--ms-font-sans);
    color: var(--ms-ink);
    margin: 0 0 0.45rem;
}
.dt-math-step p {
    font: 0.86rem/1.55 var(--ms-font-sans);
    color: var(--ms-ink-soft);
    margin: 0;
}
.dt-math-step .katex-display { margin: 0.5rem 0 0 !important; }

.dt-try {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 0.75rem;
}
.dt-try-item {
    padding: 0.85rem 1rem;
    background: var(--ms-panel-bg-soft);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-sm);
}
.dt-try-item h4 {
    font: 500 0.88rem var(--ms-font-sans);
    color: var(--ms-ink);
    margin: 0 0 0.3rem;
}
.dt-try-item p {
    font: 0.82rem/1.5 var(--ms-font-sans);
    color: var(--ms-muted);
    margin: 0;
}
.dt-try-item code {
    font: 0.78rem var(--ms-font-mono);
    color: var(--ms-accent);
    background: var(--ms-accent-soft);
    padding: 0.05rem 0.3rem;
    border-radius: 3px;
}

.dt-strip {
    display: flex; flex-wrap: wrap; gap: 0.4rem;
    align-items: center;
    padding: 0.55rem 0.85rem;
    margin: 0.65rem 0;
    border-radius: var(--ms-radius-sm);
    background: var(--ms-panel-bg-soft);
    border-left: 3px solid var(--ms-line);
}
.dt-strip-label {
    font: 500 0.7rem var(--ms-font-mono);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--ms-muted);
    margin-right: 0.4rem;
}
.dt-strip.is-watchout {
    background: rgba(245, 158, 11, 0.05);
    border-left-color: #f59e0b;
}
.dt-strip.is-watchout .dt-strip-label { color: #b45309; }
[data-theme="dark"] .dt-strip.is-watchout .dt-strip-label { color: #fbbf24; }
.dt-strip.is-practice {
    background: rgba(34, 197, 94, 0.04);
    border-left-color: #15803d;
}
.dt-strip.is-practice .dt-strip-label { color: #15803d; }
[data-theme="dark"] .dt-strip.is-practice .dt-strip-label { color: #86efac; }
.dt-tag {
    display: inline-flex; align-items: center;
    padding: 0.2rem 0.6rem;
    background: var(--ms-panel-bg);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius-pill);
    font: 500 0.76rem var(--ms-font-sans);
    color: var(--ms-ink-soft);
    white-space: nowrap;
}
.dt-strip.is-practice .dt-tag {
    font-family: var(--ms-font-mono);
    font-size: 0.74rem;
    color: var(--ms-accent);
    background: var(--ms-accent-softer);
    border-color: var(--ms-accent-soft);
}

/* ── Collapsible ───────────────────────────────────────────── */
details.dt-collapse {
    background: var(--ms-panel-bg);
    border: 1px solid var(--ms-line);
    border-radius: var(--ms-radius);
    overflow: hidden;
    margin-bottom: 1rem;
}
details.dt-collapse > summary {
    list-style: none;
    cursor: pointer;
    padding: 0.95rem 1.15rem;
    font: 500 1rem var(--ms-font-serif);
    color: var(--ms-ink);
    display: flex; justify-content: space-between; align-items: center;
    user-select: none;
}
details.dt-collapse > summary::-webkit-details-marker { display: none; }
details.dt-collapse > summary::after {
    content: '+';
    font: 500 1.3rem var(--ms-font-mono);
    color: var(--ms-muted);
}
details.dt-collapse[open] > summary::after { content: '−'; }
details.dt-collapse > .dt-collapse-body {
    padding: 0 1.15rem 1.2rem;
    border-top: 1px solid var(--ms-line);
}
details.dt-collapse > .dt-collapse-body > * + * { margin-top: 1.2rem; }
details.dt-collapse > .dt-collapse-body > *:first-child { margin-top: 1.2rem; }