:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface2: #eef0f3;
  --text: #16181b;
  --muted: #5d6470;
  --line: #dcdfe5;
  --accent: #1f6feb;
  --accent-ink: #ffffff;
  --accent-soft: #e3edfd;
  --danger: #c4312b;
  --shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 4px 16px rgba(16, 24, 40, .05);
  --mono: ui-monospace, Menlo, Consolas, "DejaVu Sans Mono", "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0f1115;
  --surface: #171a20;
  --surface2: #1f232b;
  --text: #e6e8eb;
  --muted: #9aa3af;
  --line: #2c313a;
  --accent: #5b9dff;
  --accent-ink: #0b0d10;
  --accent-soft: #1b2a44;
  --danger: #ff7b72;
  --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 6px 20px rgba(0, 0, 0, .25);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font: 15px/1.5 var(--sans);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); }
code, .mono { font-family: var(--mono); }
.small { font-size: 13px; }
.muted { color: var(--muted); }
.hidden { display: none !important; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; padding: 0; margin: -1px; }
.grow { flex: 1 1 auto; }

/* header */
.topbar {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px 20px; border-bottom: 1px solid var(--line); background: var(--surface);
  position: sticky; top: 0; z-index: 5;
}
.brand { display: flex; align-items: center; gap: 8px; min-width: 0; white-space: nowrap; }
.backlink { text-decoration: none; color: var(--muted); }
.backlink:hover { color: var(--text); }
.sep { color: var(--line); }
.topactions { display: flex; align-items: center; gap: 10px; }
.badge { font-size: 12px; color: var(--muted); border: 1px solid var(--line); border-radius: 999px; padding: 2px 10px; }

/* buttons */
button { font: inherit; cursor: pointer; border-radius: 8px; border: 1px solid transparent; padding: 7px 12px; color: var(--text); background: none; }
button:disabled { opacity: .55; cursor: default; }
button:focus-visible, select:focus-visible, input:focus-visible, .dropzone:focus-visible, pre:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.primary { background: var(--accent); color: var(--accent-ink); font-weight: 600; }
.primary:hover:not(:disabled) { filter: brightness(1.07); }
.secondary { background: var(--surface2); border-color: var(--line); }
.secondary:hover:not(:disabled) { border-color: var(--muted); }
.ghost { border-color: var(--line); }
.ghost:hover:not(:disabled) { background: var(--surface2); }
.ghost.small { padding: 5px 10px; font-size: 13px; }
.iconbtn { width: 36px; height: 36px; padding: 0; font-size: 18px; line-height: 1; }

main { max-width: 1360px; margin: 0 auto; padding: 0 20px 40px; }
.hero { padding: 28px 0 18px; }
.hero h1 { font-size: clamp(26px, 3.4vw, 38px); line-height: 1.15; margin: 0 0 8px; letter-spacing: -.01em; }
.lede { margin: 0; color: var(--muted); max-width: 760px; font-size: 16px; }

/* workspace */
.workspace { display: grid; grid-template-columns: 340px minmax(0, 1fr); gap: 20px; align-items: start; }
.panel { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); padding: 4px 16px 16px; }
.block { padding: 12px 0; border-bottom: 1px solid var(--line); }
.workspace { grid-template-columns: 360px minmax(0, 1fr); }
.block:last-of-type { border-bottom: 0; }
.block h2 { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin: 0 0 10px; font-weight: 600; }
.row { display: flex; align-items: center; flex-wrap: wrap; }
.row.gap { gap: 8px; }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip { border: 1px solid var(--line); border-radius: 999px; padding: 5px 12px; font-size: 13px; background: var(--surface); text-align: left; }
.chip:hover { border-color: var(--accent); }
.chip.on { background: var(--accent-soft); border-color: var(--accent); }

.seg { display: flex; border: 1px solid var(--line); border-radius: 10px; padding: 3px; gap: 3px; background: var(--surface2); margin-bottom: 8px; }
.segbtn { flex: 1 1 0; padding: 6px 8px; border-radius: 7px; font-size: 14px; }
.segbtn.on { background: var(--surface); box-shadow: var(--shadow); font-weight: 600; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 12px; margin-top: 6px; }
.field { display: flex; flex-direction: column; gap: 4px; margin-top: 4px; }
.field > span { font-size: 13px; color: var(--muted); display: flex; justify-content: space-between; gap: 6px; }
.field small { font-size: 12px; min-height: 1em; }
input[type=number], select {
  font: inherit; font-family: var(--mono); font-size: 14px; color: var(--text); background: var(--bg);
  border: 1px solid var(--line); border-radius: 8px; padding: 7px 9px; width: 100%; min-width: 0;
}
select { font-family: var(--sans); width: auto; padding: 5px 8px; }
input[type=number]:focus { border-color: var(--accent); outline: none; box-shadow: 0 0 0 3px var(--accent-soft); }
input[type=range] { width: 100%; accent-color: var(--accent); }
.narrow { width: 110px !important; margin-right: 10px; }
.msg { margin: 10px 0; padding: 8px 12px; border-radius: 8px; background: color-mix(in srgb, var(--danger) 12%, transparent); color: var(--danger); font-size: 13px; }
.panel .row.gap { padding-top: 10px; }

/* results */
.results { min-width: 0; }
.results.stale .cards, .results.stale .pane { opacity: .45; }
.cards { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 12px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); padding: 12px 14px; min-width: 0; }
.card .label { font-size: 12px; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); font-weight: 600; }
.card .big { font-size: 34px; font-weight: 700; letter-spacing: -.01em; line-height: 1.2; margin: 4px 0 2px; }
.card .mid { font-size: 22px; font-weight: 600; line-height: 1.3; margin: 6px 0 2px; }
.card .sub { font-size: 12.5px; color: var(--muted); overflow-wrap: anywhere; }
.hero-card { border-color: var(--accent); }
.paramline { color: var(--muted); margin: 10px 2px 4px; white-space: pre-wrap; overflow-wrap: anywhere; }
.warn { margin: 6px 0; padding: 8px 12px; border-radius: 8px; background: color-mix(in srgb, var(--ex) 14%, transparent); border: 1px solid color-mix(in srgb, var(--ex) 40%, transparent); }

.tabs { display: flex; gap: 2px; border-bottom: 1px solid var(--line); margin-top: 14px; overflow-x: auto; scrollbar-width: thin; }
.tab { border-radius: 8px 8px 0 0; padding: 9px 14px; color: var(--muted); white-space: nowrap; border-bottom: 2px solid transparent; }
.tab:hover { color: var(--text); }
.tab.on { color: var(--text); border-bottom-color: var(--accent); font-weight: 600; }
.pane { background: var(--surface); border: 1px solid var(--line); border-top: 0; border-radius: 0 0 14px 14px; padding: 14px; box-shadow: var(--shadow); min-height: 280px; }
.panehead { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 10px; margin-bottom: 6px; }
.inline { font-size: 14px; display: inline-flex; align-items: center; gap: 6px; }
.legend { display: flex; flex-wrap: wrap; gap: 6px 14px; color: var(--muted); }
.lg { display: inline-flex; align-items: center; gap: 6px; }
.sw { display: inline-block; width: 14px; height: 10px; border-radius: 3px; }
.sw-node { background: var(--surface2); border: 1px solid var(--muted); }
.sw-ex { background: color-mix(in srgb, var(--ex) 30%, var(--surface)); border: 1.5px solid var(--ex); }
.sw-itm { background: var(--surface); border: 1.5px solid var(--s3); }

/* tree */
.treewrap { overflow: auto; max-height: 72vh; border: 1px solid var(--line); border-radius: 10px; background: var(--bg); -webkit-overflow-scrolling: touch; }
#treeSvg { display: block; }
#treeSvg .edges line { stroke: var(--muted); stroke-opacity: .45; stroke-width: 1.2; }
#treeSvg .node rect { fill: var(--surface); stroke: var(--line); stroke-width: 1.2; }
#treeSvg .node { cursor: pointer; outline: none; }
#treeSvg .node text { font-family: var(--mono); font-size: 11.5px; fill: var(--text); }
#treeSvg .node .nv { fill: var(--muted); font-weight: 600; }
#treeSvg .node.root rect { stroke: var(--accent); stroke-width: 1.8; }
#treeSvg .node.itm rect { stroke: var(--s3); stroke-width: 1.8; }
#treeSvg .node.ex rect { fill: color-mix(in srgb, var(--ex) 22%, var(--surface)); stroke: var(--ex); stroke-width: 1.8; }
#treeSvg .node .extag { font-size: 10px; font-weight: 700; fill: var(--text); font-family: var(--sans); }
#treeSvg .node:hover rect, #treeSvg .node:focus-visible rect { stroke: var(--accent); stroke-width: 2.4; }
#treeSvg .node.picked rect { stroke: var(--accent); stroke-width: 2.8; }
.nodeinfo { margin-top: 10px; }
.nodeinfo dl, .ivout dl { display: grid; grid-template-columns: max-content 1fr; gap: 4px 16px; margin: 0; }
.nodeinfo dt, .ivout dt { color: var(--muted); }
.nodeinfo dd, .ivout dd { margin: 0; }
.ivout { margin-top: 14px; font-size: 15px; }
.inline-field { flex-direction: row; align-items: center; gap: 8px; }
.inline-field input { width: 140px; }

/* tables */
.tbl { width: 100%; border-collapse: collapse; font-size: 14px; }
.tbl th, .tbl td { text-align: left; padding: 7px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
.tbl thead th { font-size: 12px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
.tbl td.num { text-align: right; white-space: nowrap; }
#greekTbl td:last-child { color: var(--muted); font-size: 13px; }

/* charts */
:root { --s1: #2a78d6; --s2: #eb6834; --s3: #1baf7a; --ex: #c98500; --ref: #6b6a66; }
:root[data-theme="dark"] { --s1: #3987e5; --s2: #d95926; --s3: #199e70; --ex: #eda100; --ref: #a3a29b; }
.chart { position: relative; }
.chartbox { position: relative; }
.svgchart { display: block; width: 100%; height: auto; overflow: visible; }
.svgchart .grid line { stroke: var(--line); stroke-width: 1; }
.svgchart .axis { stroke: var(--muted); stroke-width: 1; }
.svgchart .ticklabel { fill: var(--muted); font-size: 11.5px; font-family: var(--sans); }
.svgchart .axislabel { fill: var(--muted); font-size: 12px; }
.svgchart .series { fill: none; stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.svgchart .series.dashed { stroke-dasharray: 6 5; }
.svgchart .s1, .sw.s1 { stroke: var(--s1); background: var(--s1); }
.svgchart .s2, .sw.s2 { stroke: var(--s2); background: var(--s2); }
.svgchart .s3, .sw.s3 { stroke: var(--s3); background: var(--s3); }
.svgchart .sref, .sw.sref { stroke: var(--ref); background: var(--ref); }
.sw.dashed { background: repeating-linear-gradient(90deg, var(--ref) 0 4px, transparent 4px 7px); height: 3px; }
.svgchart .dot { fill: var(--s1); stroke: var(--surface); stroke-width: 2; }
.svgchart .dot.s1 { fill: var(--s1); } .svgchart .dot.s2 { fill: var(--s2); } .svgchart .dot.s3 { fill: var(--s3); } .svgchart .dot.sref { fill: var(--ref); }
.svgchart .crosshair { stroke: var(--muted); stroke-dasharray: 3 3; }
.svgchart .vline { stroke: var(--muted); stroke-opacity: .6; stroke-dasharray: 2 4; }
.svgchart .vlabel { fill: var(--muted); font-size: 11px; }
.svgchart .hit { fill: transparent; cursor: crosshair; touch-action: pan-y; }
.chart .legend { margin: 0 0 6px; }
.tip { position: absolute; pointer-events: none; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; box-shadow: var(--shadow); padding: 6px 10px; font-size: 12.5px; min-width: 150px; z-index: 3; }
.tiphead { color: var(--muted); margin-bottom: 2px; }
.tiprow { display: flex; align-items: center; gap: 6px; white-space: nowrap; }
.tiprow b { margin-left: auto; padding-left: 10px; }

.exports { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-top: 14px; }
.secondary.small { padding: 6px 12px; font-size: 13px; }
.toast { color: var(--muted); }

.explain { margin-top: 36px; }
.explain h2 { font-size: 20px; margin: 0 0 10px; }
.explain h3 { font-size: 15px; margin: 0 0 4px; }
.explain .cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.explain p { margin: 0 0 10px; font-size: 14px; }
.explain code { font-size: 13px; background: var(--surface2); padding: 1px 5px; border-radius: 5px; }

.foot { max-width: 1360px; margin: 0 auto; padding: 16px 20px 32px; color: var(--muted); font-size: 13px; border-top: 1px solid var(--line); }
.foot p { margin: 4px 0; }

@media (max-width: 1100px) {
  .cards { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 900px) {
  .workspace { grid-template-columns: 1fr; }
  .explain .cols { grid-template-columns: 1fr; gap: 4px; }
}
@media (max-width: 560px) {
  main { padding: 0 16px 32px; }
  .topbar { padding: 8px 16px; }
  .badge { display: none; }
  .hero { padding: 18px 0 12px; }
  .lede { font-size: 15px; }
  .card .big { font-size: 28px; }
  .card .mid { font-size: 19px; }
  .pane { padding: 10px; }
  #greekTbl th:last-child, #greekTbl td:last-child { display: none; }
  .foot { padding: 16px; }
}
.lgbtn { border: 1px solid transparent; padding: 3px 8px; border-radius: 999px; color: var(--muted); font-size: 13px; }
.lgbtn:hover { border-color: var(--line); color: var(--text); }
.lgbtn.off { opacity: .5; text-decoration: line-through; }
.tblwrap { overflow-x: auto; }
#convTable { overflow-x: auto; }
@media (max-width: 560px) {
  .tbl { font-size: 13px; }
  .tbl th, .tbl td { padding: 6px 6px; }
}