/* ── Reset & base ─────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --bg:       #1e1e2e;
    --surface:  #2a2a3e;
    --border:   #3a3a5e;
    --text:     #cdd6f4;
    --muted:    #6c7086;
    --accent:   #89b4fa;
    --green:    #a6e3a1;
    --red:      #f38ba8;
    --yellow:   #f9e2af;
    --purple:   #cba6f7;
    --font:     'Segoe UI', system-ui, sans-serif;
    --mono:     'JetBrains Mono', 'Cascadia Code', Consolas, monospace;
    --radius:   6px;
    --shadow:   0 2px 8px rgba(0,0,0,.4);
}

html, body, #app { height: 100%; overflow: hidden; }
body { background: var(--bg); color: var(--text); font-family: var(--font); font-size: 14px; }

/* ── App layout ──────────────────────────────────────────────────────────── */
/* Fills the MainLayout body region (below the top nav bar), not the full viewport. */
.app-layout { display: flex; height: 100%; overflow: hidden; }

.sidebar {
    width: 280px; min-width: 220px;
    background: var(--surface); border-right: 1px solid var(--border);
    display: flex; flex-direction: column; overflow: hidden;
}
.sidebar-brand { font-size: 16px; font-weight: 700; color: var(--accent); padding: 14px 16px; border-bottom: 1px solid var(--border); letter-spacing: .5px; }
.sidebar-tabs { display: flex; border-bottom: 1px solid var(--border); }
.stab { flex: 1; padding: 8px 0; background: none; border: none; color: var(--muted); cursor: pointer; font-size: 13px; transition: color .15s, background .15s; }
.stab.active { color: var(--accent); background: rgba(137,180,250,.08); }
.stab:hover:not(.active) { color: var(--text); }
.main-content { flex: 1; display: flex; flex-direction: column; overflow: hidden; background: var(--bg); }

/* ── Buttons ─────────────────────────────────────────────────────────────── */
button { cursor: pointer; font-family: inherit; }
button:disabled { opacity: .45; cursor: not-allowed; }
.btn-primary    { background: var(--accent); color: #1e1e2e; border: none; border-radius: var(--radius); padding: 6px 14px; font-weight: 600; font-size: 13px; }
.btn-primary:hover:not(:disabled) { filter: brightness(1.12); }
.btn-secondary  { background: var(--surface); color: var(--text); border: 1px solid var(--border); border-radius: var(--radius); padding: 5px 12px; font-size: 13px; }
.btn-secondary:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.btn-run        { background: var(--green); color: #1e1e2e; border: none; border-radius: var(--radius); padding: 6px 14px; font-weight: 600; font-size: 13px; }
.btn-run:hover:not(:disabled) { filter: brightness(1.1); }
.btn-visualize  { background: var(--purple); color: #1e1e2e; border: none; border-radius: var(--radius); padding: 6px 14px; font-weight: 600; font-size: 13px; }
.btn-visualize:hover:not(:disabled) { filter: brightness(1.1); }
.btn-disconnect { background: var(--red); color: #1e1e2e; border: none; border-radius: var(--radius); padding: 5px 12px; font-size: 12px; font-weight: 600; }
.btn-delete     { background: none; border: 1px solid var(--red); color: var(--red); border-radius: var(--radius); padding: 4px 10px; font-size: 12px; }
.btn-upload     { background: var(--surface); border: 1px dashed var(--border); color: var(--accent); border-radius: var(--radius); padding: 5px 12px; font-size: 12px; cursor: pointer; }

/* ── Connection Panel ────────────────────────────────────────────────────── */
.connection-panel { border-bottom: 1px solid var(--border); }
.panel-header { display: flex; align-items: center; gap: 8px; padding: 10px 14px; cursor: pointer; user-select: none; }
.panel-header:hover { background: rgba(255,255,255,.03); }
.panel-title { font-size: 13px; font-weight: 600; flex: 1; }
.collapse-icon { color: var(--muted); font-size: 11px; }
.conn-badge { font-size: 11px; padding: 2px 8px; border-radius: 10px; }
.conn-badge.connected { background: rgba(166,227,161,.15); color: var(--green); border: 1px solid var(--green); }
.panel-body { padding: 12px 14px; }
.conn-active { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.conn-form { display: flex; flex-direction: column; gap: 12px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 12px; color: var(--muted); }
.file-row { display: flex; align-items: center; gap: 8px; }
.file-name { font-size: 12px; color: var(--muted); flex: 1; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.divider { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 11px; }
.divider::before, .divider::after { content: ''; flex: 1; border-top: 1px solid var(--border); }
.sample-buttons { display: flex; flex-direction: column; gap: 6px; }
.btn-sample { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); color: var(--text); padding: 6px 10px; font-size: 12px; text-align: left; }
.btn-sample:hover { border-color: var(--accent); color: var(--accent); }
.error-msg { color: var(--red); font-size: 12px; margin-top: 6px; }

/* ── Schema Browser ──────────────────────────────────────────────────────── */
.schema-browser { flex: 1; overflow-y: auto; padding: 8px 0; }
.browser-header { font-size: 11px; text-transform: uppercase; letter-spacing: .8px; color: var(--muted); padding: 4px 14px 8px; }
.browser-empty  { padding: 12px 14px; color: var(--muted); font-size: 13px; }
.table-list { list-style: none; }
.table-item { cursor: pointer; display: flex; flex-wrap: wrap; align-items: center; padding: 6px 14px; font-size: 13px; }
.table-item:hover { background: rgba(255,255,255,.04); }
.table-item.open .table-icon,
.table-item.open .table-name { color: var(--accent); }
.table-icon { margin-right: 4px; }
.column-list { list-style: none; background: rgba(0,0,0,.15); padding: 4px 0; flex: 0 0 100%; }
.column-item { display: flex; align-items: center; gap: 6px; padding: 4px 20px 4px 28px; font-size: 12px; }
.col-icon { width: 16px; text-align: center; }
.col-name { flex: 1; }
.col-type { color: var(--muted); font-family: var(--mono); font-size: 11px; }

/* ── Script Library ──────────────────────────────────────────────────────── */
.script-library { flex: 1; overflow-y: auto; display: flex; flex-direction: column; }
.library-header { display: flex; align-items: center; justify-content: space-between; padding: 8px 14px; border-bottom: 1px solid var(--border); font-size: 12px; font-weight: 600; }
.library-empty { padding: 14px; color: var(--muted); font-size: 12px; }
.script-list { list-style: none; }
.script-item { border-bottom: 1px solid var(--border); padding: 10px 14px; }
.script-meta { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; }
.script-name { font-size: 13px; flex: 1; }
.script-date { font-size: 11px; color: var(--muted); }
.script-actions { display: flex; gap: 6px; }
.script-results { margin-top: 8px; display: flex; flex-direction: column; gap: 4px; }
.stmt-result { font-size: 11px; display: flex; align-items: baseline; gap: 6px; flex-wrap: wrap; }
.stmt-badge { border-radius: 3px; padding: 1px 5px; font-size: 10px; font-weight: 700; }
.stmt-badge.select { background: rgba(137,180,250,.2); color: var(--accent); }
.stmt-badge.dml    { background: rgba(166,227,161,.2); color: var(--green); }
.stmt-badge.error  { background: rgba(243,139,168,.2); color: var(--red); }
.stmt-text  { color: var(--muted); font-family: var(--mono); }
.stmt-error { color: var(--red); }
.stmt-rows  { color: var(--green); }

/* ── Query Editor ────────────────────────────────────────────────────────── */
.query-editor { flex: 1; display: flex; flex-direction: column; overflow: hidden; }
.editor-toolbar { display: flex; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid var(--border); background: var(--surface); }
.loading-hint { color: var(--muted); font-size: 12px; }
.query-error  { color: var(--red); font-size: 12px; }
.monaco-wrapper { height: 220px; flex-shrink: 0; border-bottom: 1px solid var(--border); position: relative; overflow: hidden; }
.monaco-editor-container { width: 100%; height: 100%; }
.results-area { flex: 1; overflow: hidden; display: flex; flex-direction: column; }
.result-tabs { display: flex; border-bottom: 1px solid var(--border); background: var(--surface); }
.tab { padding: 7px 16px; background: none; border: none; border-bottom: 2px solid transparent; color: var(--muted); font-size: 13px; cursor: pointer; }
.tab.active { color: var(--accent); border-bottom-color: var(--accent); }
.tab:disabled { opacity: .4; cursor: not-allowed; }
.dml-result { padding: 16px; color: var(--green); font-size: 14px; }
.truncation-warning { padding: 8px 12px; background: rgba(249,226,175,.1); color: var(--yellow); font-size: 12px; }
.results-table-wrap { flex: 1; overflow: auto; }
.results-table { width: max-content; border-collapse: collapse; font-size: 13px; font-family: var(--mono); }
.results-table th { background: var(--surface); color: var(--accent); padding: 8px 14px; text-align: left; border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 1; }
.results-table td { padding: 6px 14px; border-bottom: 1px solid rgba(58,58,94,.5); white-space: nowrap; }
.results-table tr:hover td { background: rgba(255,255,255,.03); }

/* ── Animation controls ──────────────────────────────────────────────────── */
.anim-controls { display: flex; align-items: center; gap: 10px; padding: 8px 14px; background: var(--surface); border-bottom: 1px solid var(--border); flex-wrap: wrap; }
.anim-controls button { background: var(--surface); border: 1px solid var(--border); color: var(--text); border-radius: var(--radius); padding: 4px 10px; font-size: 13px; }
.anim-controls button:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.btn-step { background: transparent !important; border-color: transparent !important; color: var(--muted) !important; font-size: 11px !important; }
.btn-step:hover:not(:disabled) { border-color: var(--accent) !important; color: var(--accent) !important; }
.anim-controls label { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--muted); }
.speed-value { min-width: 14px; text-align: right; color: var(--text); font-size: 12px; }
.frame-counter { font-size: 11px; color: var(--muted); }
.phase-label    { font-size: 11px; color: var(--purple); }
.viz-header { padding: 10px 14px; border-bottom: 1px solid var(--border); display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.viz-title { font-weight: 700; color: var(--accent); }
.viz-hint  { font-size: 12px; color: var(--muted); }
.viz-hint code { font-family: var(--mono); color: var(--text); }

/* ── Sort Visualiser ─────────────────────────────────────────────────────── */
.sort-visualizer { display: flex; flex-direction: column; height: 100%; overflow: hidden; }
.sort-table-wrap { flex: 1; overflow: auto; padding: 12px; }
.sort-table { border-collapse: collapse; font-size: 13px; font-family: var(--mono); }
.sort-table th { background: var(--surface); color: var(--accent); padding: 8px 14px; text-align: left; border-bottom: 1px solid var(--border); }
.sort-table th.sort-key-col { color: var(--yellow); }
.sort-row td { padding: 6px 14px; border-bottom: 1px solid rgba(58,58,94,.4); transition: background .25s; }
.sort-row.unsorted  td { color: var(--text); }
.sort-row.comparing td { background: rgba(249,226,175,.15); color: var(--yellow); }
.sort-row.placed    td { background: rgba(166,227,161,.08); color: var(--green); }

/* ── Filter Visualiser ───────────────────────────────────────────────────── */
.filter-visualizer { display: flex; flex-direction: column; height: 100%; overflow: hidden; }
.condition-cards { display: flex; gap: 8px; padding: 8px 14px; flex-wrap: wrap; border-bottom: 1px solid var(--border); }
.condition-card { display: flex; align-items: center; gap: 6px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 5px 10px; font-size: 12px; font-family: var(--mono); }
.cond-text  { color: var(--text); }
.cond-badge { border-radius: 3px; padding: 1px 6px; font-size: 11px; font-weight: 700; }
.cond-badge.true  { background: rgba(166,227,161,.25); color: var(--green); }
.cond-badge.false { background: rgba(243,139,168,.25); color: var(--red); }
.filter-table-wrap { flex: 1; overflow: auto; padding: 12px; }
.filter-table { border-collapse: collapse; font-size: 13px; font-family: var(--mono); }
.filter-table th { background: var(--surface); color: var(--accent); padding: 8px 14px; text-align: left; border-bottom: 1px solid var(--border); }
.filter-row td { padding: 6px 14px; border-bottom: 1px solid rgba(58,58,94,.4); transition: background .2s, color .2s; }
.filter-row.pending   td { color: var(--muted); }
.filter-row.scanning  td { background: rgba(137,180,250,.15); color: var(--accent); }
.filter-row.matched   td { background: rgba(166,227,161,.1); color: var(--green); }
.filter-row.rejected  td { background: rgba(243,139,168,.05); color: rgba(243,139,168,.5); text-decoration: line-through; }
.sort-phase-label { padding: 8px 14px; color: var(--purple); font-size: 12px; }
.sort-phase-table-wrap { padding: 0 12px 12px; }

/* ── Join Visualiser ─────────────────────────────────────────────────────── */
.join-visualizer { display: flex; flex-direction: column; height: 100%; overflow: auto; }
.join-layout { display: flex; align-items: flex-start; gap: 0; padding: 12px; }
.join-side { flex: 1; min-width: 0; }
.join-table-scroll { max-height: 260px; overflow-y: auto; }
.side-title { font-size: 12px; font-weight: 700; color: var(--accent); padding: 6px 0; }
.join-table { border-collapse: collapse; width: 100%; font-size: 12px; font-family: var(--mono); }
.join-table th { background: var(--surface); color: var(--accent); padding: 6px 10px; text-align: left; border-bottom: 1px solid var(--border); }
.join-row td { padding: 5px 10px; border-bottom: 1px solid rgba(58,58,94,.4); transition: background .15s; cursor: default; }
.join-row.active    td { background: rgba(137,180,250,.18); color: var(--accent); }
.join-row.matched   td { background: rgba(166,227,161,.1); color: var(--green); }
.join-row.unmatched td { color: var(--muted); }
.join-row:hover td { background: rgba(137,180,250,.1) !important; }
.join-connectors { width: 80px; flex-shrink: 0; position: relative; align-self: stretch; }
.connector-svg { width: 100%; height: 100%; display: block; }
.merged-result { padding: 0 12px 16px; }
.merged-title { font-size: 12px; font-weight: 700; color: var(--purple); margin-bottom: 8px; }
.merged-table-wrap { overflow-x: auto; }
.merged-row-new td { background: rgba(137,180,250,.12); color: var(--accent); }

/* ── Blazor loading & error ──────────────────────────────────────────────── */
.loading-progress { position: absolute; display: block; width: 8rem; height: 8rem; inset: 20vh 0 auto 0; margin: 0 auto; }
.loading-progress circle { fill: none; stroke: #3a3a5e; stroke-width: 0.6rem; transform-origin: 50% 50%; transform: rotate(-90deg); }
.loading-progress circle:last-child { stroke: #89b4fa; stroke-dasharray: calc(3.141 * var(--blazor-load-percentage, 0%) * 0.8), 500%; transition: stroke-dasharray 0.05s ease-in-out; }
.loading-progress-text { position: absolute; text-align: center; font-weight: bold; inset: calc(20vh + 3.25rem) 0 auto 0.2rem; color: #cdd6f4; }
#blazor-error-ui { background: rgba(243,139,168,.9); bottom: 0; box-shadow: 0 -1px 2px rgba(0,0,0,.2); display: none; left: 0; padding: 0.6rem 1.25rem 0.7rem; position: fixed; width: 100%; z-index: 1000; color: #1e1e2e; }
#blazor-error-ui .dismiss { cursor: pointer; position: absolute; right: 0.75rem; top: 0.5rem; }

/* ── Results hint ────────────────────────────────────────────────────────── */
.results-hint { padding: 16px; color: var(--muted); font-size: 13px; }

/* ── Visualization modal ─────────────────────────────────────────────────── */
.viz-modal-backdrop { position: fixed; inset: 0; background: rgba(0,0,0,.62); display: flex; align-items: center; justify-content: center; z-index: 1000; }
.viz-modal { width: 92vw; height: 88vh; background: var(--bg); border: 1px solid var(--border); border-radius: 8px; box-shadow: var(--shadow); display: flex; flex-direction: column; overflow: hidden; }
.viz-modal-header { display: flex; align-items: center; justify-content: space-between; padding: 10px 16px; border-bottom: 1px solid var(--border); background: var(--surface); }
.vm-titles { display: flex; flex-direction: column; gap: 2px; }
.vm-title { font-weight: 700; color: var(--accent); font-size: 15px; }
.vm-sub { font-size: 12px; color: var(--muted); font-family: var(--mono); }
.vm-close { background: transparent; border: 1px solid var(--border); color: var(--text); border-radius: 4px; width: 28px; height: 28px; cursor: pointer; }
.vm-close:hover { border-color: var(--red); color: var(--red); }

.viz-modal-toolbar { display: flex; align-items: center; gap: 14px; padding: 8px 16px; border-bottom: 1px solid var(--border); background: var(--surface); flex-wrap: wrap; }
.viz-modal-toolbar .vm-group { display: flex; gap: 4px; }
.viz-modal-toolbar button { background: var(--surface); border: 1px solid var(--border); color: var(--text); border-radius: var(--radius); padding: 4px 10px; cursor: pointer; }
.viz-modal-toolbar button:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.viz-modal-toolbar button:disabled { opacity: .4; cursor: default; }
.vm-speed { display: flex; align-items: center; gap: 6px; font-size: 12px; color: var(--muted); }
.vm-phase { color: var(--text); font-size: 12px; margin-left: auto; font-family: var(--mono); }

.viz-modal-body { position: relative; flex: 1; overflow: hidden; }
.vm-hint { position: absolute; right: 12px; bottom: 10px; font-size: 11px; color: var(--muted); background: var(--surface); border: 1px solid var(--border); border-radius: 4px; padding: 3px 8px; pointer-events: none; }

/* ── Node canvas (pan / zoom) ────────────────────────────────────────────── */
.node-canvas { position: absolute; inset: 0; overflow: hidden; background: var(--bg); cursor: grab; touch-action: none; }
.node-canvas.dragging { cursor: grabbing; }
.nc-world { position: absolute; left: 0; top: 0; transform-origin: 0 0; will-change: transform; }
.nc-edges { position: absolute; left: 0; top: 0; overflow: visible; pointer-events: none; }
.nc-edge { stroke-width: 2; transition: stroke .15s, opacity .15s; }
.nc-edge.idle { stroke: var(--border); opacity: .5; }
/* Active connectors "draw" across the tables (and fade in) as a row forms */
.nc-edge.active { stroke: var(--accent); stroke-width: 2.5; stroke-dasharray: 1; stroke-dashoffset: 1; animation: nc-draw .4s ease-out forwards; }
@keyframes nc-draw { from { stroke-dashoffset: 1; opacity: 0; } to { stroke-dashoffset: 0; opacity: 1; } }

/* Nodes */
.nc-node { position: absolute; box-sizing: border-box; border: 1px solid var(--border); background: var(--surface); border-radius: 4px; display: flex; align-items: center; font-family: var(--mono); font-size: 12px; overflow: hidden; transition: border-color .15s, background .15s, opacity .15s; }
.nc-title { border: none; background: transparent; color: var(--accent); font-weight: 700; font-family: var(--font); font-size: 13px; padding-left: 2px; }
.nc-header { background: rgba(0,0,0,.25); color: var(--accent); font-weight: 600; }
.nc-cell { flex: 1 1 0; min-width: 0; padding: 0 8px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; border-right: 1px solid var(--border); line-height: 1; }
.nc-node > .nc-cell:last-child { border-right: none; }
.nc-card { flex-direction: column; align-items: flex-start; justify-content: center; gap: 3px; padding: 4px 10px; }
.nc-card-text { color: var(--text); }
.nc-card-badge { font-size: 10px; font-weight: 700; padding: 0 5px; border-radius: 3px; }
.nc-card-badge.true { color: var(--green); background: rgba(166,227,161,.15); }
.nc-card-badge.false { color: var(--red); background: rgba(243,139,168,.15); }
.nc-card.true { border-color: var(--green); }
.nc-card.false { border-color: var(--red); }

/* Row states */
.nc-row.dim { opacity: .25; filter: saturate(.5); }
.nc-row.pending { opacity: .45; }
.nc-row.scanning { border-color: var(--accent); background: rgba(137,180,250,.2); color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.nc-row.read { opacity: .85; }
.nc-row.active { border-color: var(--yellow); background: rgba(249,226,175,.16); }
.nc-row.matched { border-color: var(--green); background: rgba(166,227,161,.14); }
.nc-row.placed { border-color: var(--green); }
.nc-row.rejected { opacity: .32; text-decoration: line-through; }
.nc-row.new { border-color: var(--accent); background: rgba(137,180,250,.24); animation: nc-pop .3s ease; }
.nc-row.kept { border-color: var(--green); background: rgba(166,227,161,.14); }
.nc-row.cut { opacity: .3; text-decoration: line-through; border-color: var(--red); }
@keyframes nc-pop { from { transform: scale(.95); } to { transform: scale(1); } }

/* ── Learn section ───────────────────────────────────────────────────────── */
.learn-page { height: 100%; overflow-y: auto; padding: 32px 40px 80px; }
.learn-hero h1 { font-size: 26px; color: var(--accent); margin-bottom: 6px; }
.learn-hero p { color: var(--muted); max-width: 640px; margin-bottom: 28px; }
.learn-status { color: var(--muted); padding: 20px 0; }
.learn-error { color: var(--red); padding: 16px 0; }

.lesson-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; max-width: 900px; }
.lesson-card { display: block; position: relative; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; text-decoration: none; color: var(--text); transition: border-color .15s, transform .15s; }
.lesson-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.lesson-card h3 { color: var(--accent); margin: 8px 0 6px; font-size: 16px; }
.lesson-card p { color: var(--muted); font-size: 13px; line-height: 1.5; }
.lc-badge { position: absolute; top: 14px; right: 14px; font-size: 10px; text-transform: uppercase; letter-spacing: .5px; color: var(--muted); border: 1px solid var(--border); border-radius: 10px; padding: 1px 8px; }

/* Lesson view */
.lesson-view { max-width: 860px; margin: 0 auto; }
.lesson-topline { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 18px; }
.lesson-back { color: var(--muted); text-decoration: none; font-size: 13px; }
.lesson-back:hover { color: var(--accent); }
.lesson-db { display: flex; align-items: center; gap: 8px; font-size: 12px; color: var(--muted); }
.lesson-db strong { color: var(--text); }
.db-ok { color: var(--green); }
.db-err { color: var(--red); }
.db-reset { padding: 3px 10px !important; font-size: 12px; }
.lesson-title { font-size: 24px; color: var(--text); margin-bottom: 20px; }

/* Rendered markdown body */
.lesson-body { line-height: 1.65; color: var(--text); }
.lesson-body h1, .lesson-body h2, .lesson-body h3 { color: var(--accent); margin: 26px 0 10px; }
.lesson-body h2 { font-size: 20px; border-bottom: 1px solid var(--border); padding-bottom: 6px; }
.lesson-body h3 { font-size: 16px; }
.lesson-body p { margin: 10px 0; }
.lesson-body ul, .lesson-body ol { margin: 10px 0 10px 24px; }
.lesson-body li { margin: 4px 0; }
.lesson-body strong { color: var(--text); font-weight: 700; }
.lesson-body a { color: var(--accent); }
.lesson-body code { font-family: var(--mono); background: var(--surface); border: 1px solid var(--border); border-radius: 4px; padding: 1px 5px; font-size: 12.5px; color: var(--yellow); }
.lesson-body pre { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px; overflow-x: auto; margin: 12px 0; }
.lesson-body pre code { background: none; border: none; padding: 0; color: var(--text); }
.lesson-body blockquote { border-left: 3px solid var(--accent); padding-left: 14px; color: var(--muted); margin: 12px 0; }
.lesson-body table { border-collapse: collapse; margin: 12px 0; }
.lesson-body th, .lesson-body td { border: 1px solid var(--border); padding: 5px 10px; font-size: 13px; }

/* Interactive lesson cell (notebook node) */
.lesson-cell { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); margin: 16px 0; overflow: hidden; }
.lc-toolbar { display: flex; align-items: center; gap: 10px; padding: 8px 10px; border-bottom: 1px solid var(--border); }
.lc-hint { color: var(--muted); font-size: 12px; }
.lc-error { color: var(--red); font-size: 12px; font-family: var(--mono); }
.lc-editor { background: #1e1e1e; }
.lc-results { padding: 8px 10px; border-top: 1px solid var(--border); }
.lc-dml { color: var(--green); font-size: 13px; }
.lc-trunc { color: var(--yellow); font-size: 12px; margin-bottom: 6px; }
.lc-table-wrap { max-height: 260px; overflow: auto; border: 1px solid var(--border); border-radius: 4px; }
.lc-rowcount { color: var(--muted); font-size: 11px; margin-top: 5px; }

/* ── Scrollbar ───────────────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--muted); }


/* ── Learn: course path (index page) ─────────────────────────────────────── */
.course-progress { display: flex; align-items: center; gap: 12px; max-width: 720px; margin-bottom: 26px; }
.course-reset { margin-left: auto; }
.ps-bar { flex: 1; height: 8px; background: var(--surface); border: 1px solid var(--border); border-radius: 5px; overflow: hidden; }
.ps-bar-fill { height: 100%; background: linear-gradient(90deg, var(--accent), var(--green)); transition: width .3s; }
.ps-count { color: var(--muted); font-size: 12px; white-space: nowrap; }

.course-path { max-width: 720px; }
.unit-card { display: flex; gap: 16px; }
.unit-marker { display: flex; flex-direction: column; align-items: center; width: 34px; flex-shrink: 0; }
.um-icon { width: 32px; height: 32px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 14px; flex-shrink: 0; }
.um-done { background: var(--green); color: #1e1e2e; }
.um-current { background: var(--accent); color: #1e1e2e; box-shadow: 0 0 0 4px rgba(137,180,250,.25); }
.um-locked { background: var(--surface); color: var(--muted); border: 1px solid var(--border); }
.um-line { flex: 1; width: 2px; background: var(--border); margin: 4px 0; min-height: 24px; }

.unit-body { flex: 1; padding-bottom: 18px; }
.unit-link { display: block; width: 100%; text-align: left; position: relative; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px 18px; text-decoration: none; color: var(--text); transition: border-color .15s, transform .15s; font: inherit; cursor: pointer; }
a.unit-link:hover { border-color: var(--accent); transform: translateY(-2px); }
.unit-current .unit-link { border-color: var(--accent); }
.unit-link-locked { opacity: .65; }
.unit-link-locked:hover { opacity: .85; border-color: var(--muted); }
.ucb h3 { color: var(--accent); margin: 6px 0 6px; font-size: 16px; }
.unit-locked .ucb h3 { color: var(--muted); }
.ucb p { color: var(--muted); font-size: 13px; line-height: 1.5; margin: 0 0 8px; }
.ucb-lock { font-size: 12px; }
.ucb-exercises { font-size: 11px; color: var(--muted); border: 1px solid var(--border); border-radius: 10px; padding: 1px 8px; }
.unit-done .ucb-exercises { color: var(--green); border-color: var(--green); }

.unit-skip-confirm { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--border); font-size: 13px; color: var(--text); }

/* ── Learn: lesson footer / completion ───────────────────────────────────── */
.lesson-complete-badge { font-size: 12px; color: var(--green); border: 1px solid var(--green); border-radius: 10px; padding: 2px 10px; margin-left: 10px; vertical-align: middle; }
.lesson-footer { display: flex; align-items: center; gap: 16px; margin-top: 36px; padding-top: 18px; border-top: 1px solid var(--border); }
.lesson-next { margin-left: auto; color: var(--accent); text-decoration: none; font-weight: 600; }
.lesson-next:hover { text-decoration: underline; }
.lesson-next-done { margin-left: auto; color: var(--green); }

/* ── Learn: practice section ─────────────────────────────────────────────── */
.practice-section, .quiz-section { margin-top: 40px; }
.practice-section h2, .quiz-section h2 { color: var(--accent); font-size: 20px; border-bottom: 1px solid var(--border); padding-bottom: 6px; margin-bottom: 10px; }
.ps-intro { color: var(--muted); font-size: 13.5px; line-height: 1.6; margin-bottom: 14px; }
.ps-progressline { display: flex; align-items: center; gap: 12px; margin-bottom: 18px; }
.ps-done { color: var(--green); font-size: 15px; font-weight: 600; margin-top: 18px; }

.practice-problem { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); margin: 10px 0; overflow: hidden; }
.practice-problem.pp-solved { border-color: rgba(166,227,161,.5); }
.pp-header { display: flex; align-items: flex-start; gap: 10px; width: 100%; text-align: left; background: none; border: none; color: var(--text); font: inherit; font-size: 13.5px; padding: 10px 12px; cursor: pointer; }
.pp-header:hover { background: rgba(137,180,250,.06); }
.pp-status { flex-shrink: 0; width: 22px; height: 22px; border-radius: 50%; background: var(--bg); border: 1px solid var(--border); color: var(--muted); display: flex; align-items: center; justify-content: center; font-size: 11px; font-weight: 700; }
.pp-solved .pp-status { background: var(--green); color: #1e1e2e; border-color: var(--green); }
.pp-prompt { flex: 1; line-height: 1.5; }
.pp-prompt code { font-family: var(--mono); background: var(--bg); border: 1px solid var(--border); border-radius: 4px; padding: 0 4px; font-size: 12px; color: var(--yellow); }
.pp-chevron { color: var(--muted); flex-shrink: 0; }
.pp-body { border-top: 1px solid var(--border); }
.pp-hint { padding: 8px 12px; font-size: 13px; color: var(--yellow); background: rgba(249,226,175,.07); border-bottom: 1px solid var(--border); }
.pp-hint code { font-family: var(--mono); font-size: 12px; }
.pp-solution { margin: 0; padding: 10px 12px; background: var(--bg); border-bottom: 1px solid var(--border); font-family: var(--mono); font-size: 12.5px; color: var(--text); overflow-x: auto; white-space: pre-wrap; }
.pp-feedback { padding: 8px 12px; font-size: 13px; border-top: 1px solid var(--border); }
.pp-ok { color: var(--green); }
.pp-bad { color: var(--red); }
.btn-check { background: var(--green); color: #1e1e2e; border: none; border-radius: 4px; padding: 4px 12px; font-size: 12.5px; font-weight: 600; cursor: pointer; }
.btn-check:hover:not(:disabled) { filter: brightness(1.1); }
.btn-check:disabled { opacity: .45; cursor: default; }

/* ── Learn: quiz ─────────────────────────────────────────────────────────── */
.quiz-best { font-size: 12.5px; color: var(--muted); margin-bottom: 14px; }
.quiz-question { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; margin: 10px 0; }
.quiz-question.qq-right { border-color: rgba(166,227,161,.6); }
.quiz-question.qq-wrong { border-color: rgba(243,139,168,.6); }
.qq-text { font-size: 14px; line-height: 1.55; margin-bottom: 10px; }
.qq-text code, .qq-choices code, .qq-explain code { font-family: var(--mono); background: var(--bg); border: 1px solid var(--border); border-radius: 4px; padding: 0 4px; font-size: 12px; color: var(--yellow); }
.qq-num { color: var(--muted); font-weight: 700; margin-right: 4px; }
.qq-choices { display: flex; flex-direction: column; gap: 6px; }
.qq-choice { display: flex; align-items: baseline; gap: 8px; padding: 6px 10px; border: 1px solid var(--border); border-radius: 4px; font-size: 13px; cursor: pointer; line-height: 1.5; }
.qq-choice:hover { border-color: var(--accent); }
.qq-choice input { accent-color: var(--accent); }
.qq-selected { border-color: var(--accent); background: rgba(137,180,250,.08); }
.qq-correct { border-color: var(--green); background: rgba(166,227,161,.08); }
.qq-incorrect { border-color: var(--red); background: rgba(243,139,168,.08); }
.qq-explain { margin-top: 10px; padding: 8px 10px; font-size: 12.5px; color: var(--muted); background: var(--bg); border-radius: 4px; line-height: 1.55; }
.quiz-footer { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin: 18px 0 40px; }
.quiz-submit { padding: 8px 18px; font-size: 14px; }
.quiz-score { font-size: 14px; }
.qs-pass { color: var(--green); }
.qs-fail { color: var(--yellow); }

/* ── Learn: inline schema peek ───────────────────────────────────────────── */
.schema-peek { padding: 8px 12px; border-bottom: 1px solid var(--border); background: rgba(137,180,250,.05); font-size: 12.5px; }
.sp-empty { color: var(--muted); }
.sp-table { display: flex; align-items: baseline; gap: 10px; padding: 3px 0; flex-wrap: wrap; }
.sp-table-name { font-family: var(--mono); font-weight: 700; color: var(--accent); white-space: nowrap; }
.sp-cols { display: flex; flex-wrap: wrap; gap: 6px; }
.sp-col { font-family: var(--mono); font-size: 11.5px; color: var(--text); background: var(--bg); border: 1px solid var(--border); border-radius: 4px; padding: 1px 6px; white-space: nowrap; }
.sp-key { font-size: 10px; margin-right: 2px; }
.sp-type { color: var(--muted); font-size: 10px; }