/* Lawson Explorer: a paper-and-instrument scientific workbench. */
:root {
  color-scheme: light;
  --paper: #f3f5f1;
  --panel: #ffffff;
  --ink: #122126;
  --muted: #526167;
  --line: #cdd5d1;
  --line-strong: #879691;
  --plasma: #007f83;
  --plasma-dark: #005c60;
  --plasma-wash: #dceff0;
  --ignition: #c86a1b;
  --ignition-dark: #91470e;
  --ignition-wash: #f5e5d6;
  --danger: #9a3333;
  --shadow: 0 14px 38px rgba(18, 33, 38, 0.08);
  --radius: 3px;
  --font-display: "Arial Narrow", "Aptos Narrow", "Roboto Condensed", "Noto Sans Condensed", "Liberation Sans Narrow", sans-serif;
  --font-equation: Georgia, "Times New Roman", serif;
  --font-body: "Aptos", "Segoe UI", "Noto Sans", Arial, sans-serif;
  /* IBM Plex Mono is the intended data face but is not loaded yet; keep it
     last as an opportunistic local fallback until P1 self-hosting lands. */
  --font-data: "SFMono-Regular", Consolas, "Liberation Mono", "IBM Plex Mono", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; text-size-adjust: 100%; -webkit-text-size-adjust: 100%; }
body {
  min-width: 320px;
  margin: 0;
  background: linear-gradient(rgba(18, 33, 38, 0.025) 1px, transparent 1px), var(--paper);
  background-size: 100% 32px;
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.5;
}
button, input { color: inherit; font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: 0.48; }
:focus-visible { outline: 3px solid var(--ignition); outline-offset: 3px; }

.skip-link {
  position: fixed;
  z-index: 100;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.65rem 0.85rem;
  transform: translateY(-160%);
  background: var(--ink);
  color: white;
}
.skip-link:focus { transform: none; }

.site-header {
  display: grid;
  min-height: 84px;
  grid-template-columns: minmax(150px, 1fr) minmax(260px, 2fr) minmax(150px, 1fr);
  align-items: center;
  gap: 1.5rem;
  padding: 0.75rem clamp(1rem, 3vw, 3.5rem);
  border-bottom: 1px solid var(--line-strong);
  background: rgba(243, 245, 241, 0.96);
}
.brand { display: inline-flex; align-items: center; width: fit-content; gap: 0.65rem; color: var(--ink); font-weight: 750; letter-spacing: 0.02em; text-decoration: none; }
.brand-mark { display: grid; width: 2.4rem; height: 2.4rem; place-items: center; border: 1px solid var(--ink); font-family: var(--font-equation); font-style: italic; }
.title-block { text-align: center; }
.title-block h1, .workspace-masthead h2, .rail-heading h2, .results-placeholder h3 { margin: 0; font-family: var(--font-display); font-weight: 500; letter-spacing: -0.025em; }
.title-block h1 { font-size: clamp(1.6rem, 3vw, 2.8rem); line-height: 0.95; }
.eyebrow, .chart-code { margin: 0 0 0.35rem; color: var(--plasma-dark); font-family: var(--font-data); font-size: 0.68rem; font-weight: 700; letter-spacing: 0.11em; text-transform: uppercase; }
.chart-code { margin-bottom: 0.15rem; }
.header-actions { justify-self: end; display: flex; align-items: center; gap: 0.55rem; min-width: 0; }
.help-menu-wrap { position: relative; }
.header-tool, .help-menu button, .help-menu a { border: 1px solid var(--line-strong); padding: 0.55rem 0.7rem; background: var(--panel); font-family: var(--font-data); font-size: 0.78rem; font-weight: 700; }
.header-tool:hover, .help-menu button:hover, .help-menu a:hover { border-color: var(--plasma-dark); color: var(--plasma-dark); }
.help-menu { position: absolute; z-index: 20; top: calc(100% + 0.4rem); right: 0; display: none; min-width: 8.6rem; border: 1px solid var(--line-strong); padding: 0.35rem; background: var(--panel); box-shadow: var(--shadow); }
.help-menu.on { display: grid; }
.help-menu button, .help-menu a { display: block; width: 100%; border: 0; color: inherit; text-align: left; text-decoration: none; }
.status-banner { padding: 0.7rem clamp(1rem, 3vw, 3.5rem); border-bottom: 1px solid var(--plasma); background: var(--plasma-wash); font-size: 0.88rem; }
.status-banner--warning { border-color: var(--ignition); background: var(--ignition-wash); }

.workbench { display: grid; grid-template-columns: minmax(260px, 340px) minmax(0, 1fr); max-width: 1720px; min-height: calc(100vh - 84px); margin: 0 auto; }
.equation-rail { position: sticky; top: 0; align-self: start; height: calc(100vh - 84px); overflow-x: hidden; overflow-y: auto; padding: clamp(1rem, 2vw, 1.75rem); border-right: 1px solid var(--ink); background: var(--ink); color: #edf5f2; }
.equation-rail::before { position: absolute; inset: -11rem -9rem auto auto; width: 21rem; height: 21rem; border: 1px solid rgba(105, 225, 226, 0.22); border-radius: 50%; box-shadow: 0 0 0 2.7rem rgba(105, 225, 226, 0.035), 0 0 0 5.4rem rgba(105, 225, 226, 0.025); content: ""; pointer-events: none; }
.rail-heading { position: relative; }
.rail-index { margin: 0 0 0.75rem; color: #78d9dc; font-family: var(--font-equation); font-size: clamp(2.2rem, 3.5vw, 3.5rem); font-style: italic; line-height: 0.8; letter-spacing: -0.07em; }
.rail-heading h2 { font-size: 1.4rem; }
.rail-heading p:last-child { margin: 0.5rem 0 0; color: #b9c8c5; font-size: 0.88rem; }
.calculator-form { display: grid; grid-template-columns: minmax(2.1rem, auto) minmax(0, 1fr) auto; gap: 0.45rem; margin: 1rem 0 0.75rem; }
.calculator-field { position: relative; display: grid; grid-column: 1 / -1; grid-template-columns: subgrid; align-items: center; gap: 0.55rem; min-width: 0; }
.calculator-form label { color: #eef9f7; font-family: var(--font-equation); font-size: 1.25rem; white-space: nowrap; }
.calculator-form .unit { color: #98aaa7; font-family: var(--font-data); font-size: 0.64rem; font-style: normal; white-space: nowrap; }
.calculator-form input { width: 100%; min-width: 0; border: 0; border-bottom: 1px solid #50625f; border-radius: 0; padding: 0.45rem 0; background: transparent; color: #77e0e2; font-family: var(--font-data); font-size: 1rem; text-align: center; }
.calculator-form input:focus { border-color: #77e0e2; outline: 0; box-shadow: 0 2px 0 #77e0e2; }
.field-tooltip { position: absolute; z-index: 15; top: calc(100% + 0.35rem); left: 0; display: none; width: min(19rem, calc(100vw - 3rem)); margin: 0; border: 1px solid #77e0e2; padding: 0.65rem 0.75rem; background: #edf5f2; color: var(--ink); font-size: 0.72rem; line-height: 1.45; pointer-events: none; box-shadow: 0 9px 22px rgba(0, 0, 0, 0.24); }
.calculator-field:hover .field-tooltip, .calculator-field:focus-within .field-tooltip { display: block; }
.equation-results { margin: 0 0 0.75rem; border-top: 1px solid #50625f; }
.result-block { display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.5rem; padding: 0.6rem 0; border-bottom: 1px solid #50625f; }
.result-block output { padding: 0 0.25rem; color: #77e0e2; font-family: var(--font-data); font-size: 1.2rem; letter-spacing: -0.02em; white-space: nowrap; }
.result-block--amber output { color: #f0a45f; }
.result-label { font-family: var(--font-equation); font-size: 1rem; }
.result-unit { color: #98aaa7; font-family: var(--font-data); font-size: 0.68rem; }
.calculator-error { margin: 1rem 0 0; border-left: 3px solid #f0a45f; padding-left: 0.7rem; color: #ffd0a4; font-size: 0.8rem; }
.calculator-actions { display: grid; grid-template-columns: 1fr auto; gap: 0.5rem; margin-top: 0.75rem; }
.button { min-height: 2.55rem; border: 1px solid var(--line-strong); border-radius: var(--radius); padding: 0.55rem 0.85rem; background: var(--panel); font-family: var(--font-data); font-size: 0.74rem; font-weight: 700; }
.button:hover { border-color: var(--ink); }
.button--primary { border-color: var(--plasma); background: var(--plasma); color: white; }
.button--primary:hover { border-color: var(--plasma-dark); background: var(--plasma-dark); }
.button--quiet { background: transparent; }
.button--rail { width: 100%; border-color: #77e0e2; background: #77e0e2; color: var(--ink); }
.button--rail:hover { background: #b9fbfc; }
.button--rail-quiet { width: auto; border-color: #50625f; background: transparent; color: #c5d5d2; }
.button--rail-quiet:hover { border-color: #77e0e2; background: transparent; color: #77e0e2; }
.rail-note { color: #98aaa7; font-size: 0.74rem; }

.visually-hidden { position: absolute !important; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.workspace-panel { min-width: 0; padding: 1rem clamp(1.25rem, 3vw, 3.5rem); }
.results-placeholder { display: grid; min-height: 440px; align-content: center; border: 1px solid var(--line-strong); padding: clamp(1.5rem, 6vw, 5rem); background: rgba(255, 255, 255, 0.68); box-shadow: var(--shadow); }
.results-placeholder[hidden], .results-region[hidden] { display: none; }
.placeholder-mark { margin: 0 0 1rem; color: var(--ignition); font-family: var(--font-equation); font-size: clamp(3rem, 8vw, 6rem); font-style: italic; line-height: 0.7; }
.results-placeholder h3 { font-size: clamp(2rem, 5vw, 4.25rem); line-height: 0.95; }
.results-placeholder > p:last-child { max-width: 44rem; margin: 1rem 0 0; color: var(--muted); }
.results-region[aria-busy="true"] { opacity: 0.7; }
.view-toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 0.75rem; margin: 0 0 0.5rem; }
.segmented-control { display: inline-flex; border: 1px solid var(--line-strong); }
.segmented-control button { border: 0; padding: 0.55rem 0.8rem; background: transparent; font-family: var(--font-data); font-size: 0.72rem; }
.segmented-control button + button { border-left: 1px solid var(--line-strong); }
.segmented-control button[aria-pressed="true"] { background: var(--ink); color: white; }
.results-stack { display: grid; grid-template-columns: minmax(0, 1fr); gap: 0.5rem; }
.chart-card { min-width: 0; border: 1px solid var(--line); background: var(--panel); box-shadow: var(--shadow); }
.chart-card > header { position: relative; padding: 0.55rem 1rem; border-bottom: 1px solid var(--line); }
.chart-title { display: flex; align-items: baseline; gap: 0.6rem; width: fit-content; }
.chart-title .chart-code { margin: 0; }
.chart-card h3 { margin: 0; font-family: var(--font-display); font-size: 1.1rem; font-weight: 500; }
.chart-note { position: absolute; z-index: 15; top: calc(100% + 0.35rem); left: 1rem; display: none; width: min(24rem, calc(100vw - 3rem)); margin: 0; border: 1px solid var(--plasma); padding: 0.65rem 0.75rem; background: var(--panel); color: var(--muted); font-size: 0.72rem; line-height: 1.45; pointer-events: none; box-shadow: var(--shadow); }
.chart-title:hover + .chart-note, .chart-title:focus + .chart-note { display: block; }
.plot { width: 100%; height: clamp(240px, 32vh, 440px); }
.table-wrap { max-height: clamp(240px, 32vh, 440px); overflow: auto; }
.results-stack[data-mode="table"] .plot { display: none; }
.results-stack[data-mode="table"] .table-wrap { display: block; }
.data-table { width: 100%; border-collapse: collapse; font-size: 0.72rem; }
.data-table th { position: sticky; z-index: 1; top: 0; background: var(--ink); color: white; text-align: left; }
.data-table th, .data-table td { padding: 0.55rem 0.6rem; border-bottom: 1px solid var(--line); vertical-align: top; }
.data-table tbody tr:first-child { background: var(--plasma-wash); }
.data-table .numeric { font-family: var(--font-data); text-align: right; white-space: nowrap; }
.current-badge { display: inline-block; margin-top: 0.2rem; border: 1px solid var(--plasma-dark); padding: 0.08rem 0.28rem; color: var(--plasma-dark); font-family: var(--font-data); font-size: 0.58rem; text-transform: uppercase; }
.empty-state { padding: 2rem; color: var(--muted); text-align: center; }
.dataset-footer { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; margin-top: 1rem; border: 1px solid var(--line); padding: 1rem; background: rgba(255, 255, 255, 0.78); color: var(--muted); font-size: 0.72rem; }
.dataset-footer p { margin: 0.25rem 0 0; }
.license-link { display: inline-block; margin-top: 0.35rem; color: var(--plasma-dark); text-underline-offset: 0.2em; }

.rail-details { position: relative; margin-top: 1.35rem; border-top: 1px solid #50625f; }
.rail-details summary { padding: 0.55rem 0; color: #e5f4f1; font-family: var(--font-data); font-size: 0.74rem; font-weight: 700; cursor: pointer; }
.rail-details summary::marker { color: #77e0e2; }
.rail-details__content { display: grid; gap: 0.7rem; padding: 0 0 0.5rem; }
#reset-filters { margin-top: 1rem; }
.rail-details__content label { display: grid; grid-template-columns: minmax(6.2rem, 0.8fr) minmax(0, 1.2fr); align-items: center; gap: 0.5rem; color: #b9c8c5; font-size: 0.72rem; }
.rail-details__content input, .rail-details__content select { min-width: 0; border: 1px solid #50625f; border-radius: 0; padding: 0.3rem 0.45rem; background: #172d33; color: #edf5f2; font-family: var(--font-data); font-size: 0.74rem; }
.rail-details__content input:focus, .rail-details__content select:focus { border-color: #77e0e2; outline: 0; box-shadow: 0 0 0 2px rgba(119, 224, 226, 0.25); }

.workspace-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem; margin-left: auto; }
.menu-wrap { position: relative; }
.menu-pop { position: absolute; z-index: 20; top: calc(100% + 0.35rem); left: 0; display: none; min-width: 12rem; border: 1px solid var(--line-strong); padding: 0.3rem; background: var(--panel); box-shadow: var(--shadow); }
.menu-pop.on { display: grid; }
.menu-pop button { border: 0; padding: 0.6rem; background: transparent; color: inherit; font: 700 0.72rem var(--font-data); text-align: left; white-space: nowrap; }
.menu-pop button:hover { color: var(--plasma-dark); background: var(--plasma-wash); }
#save-menu { right: 0; left: auto; }
.data-tools-dialog { width: min(760px, calc(100vw - 2rem)); max-height: min(78vh, 720px); border: 1px solid var(--ink); padding: 0; background: var(--panel); color: var(--ink); box-shadow: 0 24px 72px rgba(0, 0, 0, 0.28); }
.data-tools-dialog::backdrop { background: rgba(18, 33, 38, 0.5); }
.data-tools-dialog__header { display: flex; align-items: center; justify-content: space-between; gap: 1rem; border-bottom: 1px solid var(--line); padding: 1rem; }
.data-tools-dialog__header h2, .data-tools-dialog h3 { margin: 0; font-family: var(--font-display); font-weight: 500; }
.data-tools-dialog section { padding: 1rem; }
.data-tools-dialog section > p { margin-top: 0; color: var(--muted); }
.comparison-grid { display: grid; grid-template-columns: minmax(7rem, 1fr) minmax(0, 1.2fr) minmax(0, 1.2fr) minmax(5rem, 0.7fr); overflow: auto; border-top: 1px solid var(--line); border-left: 1px solid var(--line); font-size: 0.75rem; }
.comparison-grid > div { min-width: 7rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: 0.5rem; overflow-wrap: anywhere; }
.comparison-grid .comparison-head { background: var(--ink); color: white; font-family: var(--font-data); font-size: 0.68rem; }
.comparison-warning { border-left: 3px solid var(--ignition); padding-left: 0.65rem; color: var(--ignition-dark) !important; }
.comparison-compatible { border-left: 3px solid var(--plasma); padding-left: 0.65rem; }
.user-point-row { display: flex; align-items: start; justify-content: space-between; gap: 1rem; border-top: 1px solid var(--line); padding: 0.8rem 0; font-size: 0.8rem; }
.user-point-row p { margin: 0.25rem 0 0; color: var(--muted); }
.row-actions { display: flex; gap: 0.4rem; }
.row-actions button { border: 1px solid var(--line-strong); padding: 0.35rem 0.45rem; background: var(--panel); font: 700 0.65rem var(--font-data); }
.history-toolbar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.7rem; margin: 0 0 1rem; }
.history-chart-card { min-width: 0; border-top: 1px solid var(--line); padding-top: 0.85rem; }
.history-chart-card h4 { margin: 0; font-family: var(--font-display); font-size: 1.1rem; font-weight: 500; }
.history-chart-card > p:not(.chart-code) { margin: 0.35rem 0 0.75rem; color: var(--muted); font-size: 0.74rem; }
.history-plot { height: min(48vh, 390px); }
.history-table { max-height: min(48vh, 390px); border: 1px solid var(--line); }

.manual-document { max-width: 1280px; margin: 0 auto; padding: clamp(1.5rem, 4vw, 4rem); }
.manual-document__layout { display: grid; grid-template-columns: minmax(12rem, 17rem) minmax(0, 1fr); gap: clamp(1.5rem, 5vw, 5rem); align-items: start; }
.manual-toc { position: sticky; top: 1.5rem; border-top: 2px solid var(--ink); padding-top: 0.75rem; }
.manual-toc h2 { margin: 0 0 0.7rem; font-family: var(--font-data); font-size: 0.74rem; letter-spacing: 0.1em; text-transform: uppercase; }
.manual-toc a { display: block; padding: 0.4rem 0; color: var(--muted); font-size: 0.84rem; text-decoration: none; }
.manual-toc a:hover { color: var(--plasma-dark); text-decoration: underline; }
.manual-content { min-width: 0; }
.manual-content h1 { margin: 0; font-family: var(--font-display); font-size: clamp(2.7rem, 6vw, 5.8rem); font-weight: 500; letter-spacing: -0.035em; line-height: 0.88; }
.manual-lead { max-width: 50rem; margin: 1.25rem 0 3rem; color: var(--muted); font-size: 1.05rem; }
.manual-section { scroll-margin-top: 1.5rem; margin-bottom: 3rem; border-top: 1px solid var(--line-strong); padding-top: 1rem; }
.manual-section h2 { margin: 0 0 0.75rem; font-family: var(--font-display); font-size: clamp(1.7rem, 3vw, 2.6rem); font-weight: 500; line-height: 1; }
.manual-section h3 { margin: 1.25rem 0 0.55rem; color: var(--plasma-dark); font-family: var(--font-data); font-size: 0.76rem; letter-spacing: 0.1em; text-transform: uppercase; }
.manual-section p, .manual-section li { max-width: 50rem; font-size: 0.94rem; }
.manual-section p { margin: 0 0 0.85rem; }
.manual-section ol, .manual-section ul { margin: 0.6rem 0 0; padding-left: 1.3rem; }
.manual-section li + li { margin-top: 0.45rem; }
.manual-equation { max-width: 50rem; margin: 0.9rem 0; border-left: 3px solid var(--ignition); padding: 0.85rem 1rem; background: var(--ignition-wash); font-family: var(--font-equation); font-size: 1.12rem; }
.manual-note { max-width: 50rem; border: 1px solid var(--line-strong); padding: 0.9rem 1rem; background: rgba(255, 255, 255, 0.72); }
.manual-note strong { color: var(--ignition-dark); }
.manual-table { width: 100%; max-width: 56rem; border-collapse: collapse; font-size: 0.82rem; }
.manual-table th, .manual-table td { padding: 0.6rem; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.manual-table th { background: var(--ink); color: white; font-family: var(--font-data); font-size: 0.7rem; font-weight: 500; }
.manual-table td:first-child { width: 28%; color: var(--plasma-dark); font-family: var(--font-data); }
.manual-references { margin: 0; padding-left: 1.25rem; }
.manual-references li { margin-bottom: 0.65rem; }
.manual-return { color: var(--plasma-dark); font-family: var(--font-data); font-size: 0.78rem; text-underline-offset: 0.25em; }

@media (max-width: 760px) {
  .site-header { min-height: auto; grid-template-columns: 1fr auto; gap: 0.7rem; padding: 0.9rem 1rem; }
  .brand > span:last-child { display: none; }
  .title-block { grid-row: 2; grid-column: 1 / -1; text-align: left; }
  .title-block h1 { font-size: 1.9rem; }
  .header-actions { grid-row: 1; grid-column: 2; gap: 0.35rem; }
  .header-tool { padding: 0.55rem; }
  .workbench { display: block; }
  .equation-rail { position: relative; min-height: auto; height: auto; overflow: hidden; padding: 1.5rem; border-right: 0; }
  .equation-rail::before { width: 15rem; height: 15rem; }
  .rail-index { margin-bottom: 1rem; font-size: 3.4rem; }
  .calculator-field { gap: 0.45rem; }
  .calculator-form label { font-size: 1.1rem; }
  .calculator-form input { font-size: 0.95rem; }
  .field-tooltip { width: min(19rem, calc(100vw - 3rem)); }
  .result-block { min-width: 0; }
  .result-block output { font-size: 1.1rem; }
  .workspace-panel { padding: 1rem; }
  .workspace-actions { gap: 0.45rem; }
  .user-point-row { display: block; }
  .row-actions { margin-top: 0.65rem; }
  .data-tools-dialog { width: calc(100vw - 1rem); }
  .comparison-grid { grid-template-columns: 7rem 10rem 10rem 5rem; }
  .results-placeholder { min-height: 270px; }
  .view-toolbar { align-items: stretch; flex-wrap: wrap; }
  .plot { height: 365px; }
  .dataset-footer { grid-template-columns: 1fr; gap: 1rem; }
  .manual-document { min-width: 0; padding: 1.25rem 1rem 2rem; }
  .manual-document__layout { min-width: 0; grid-template-columns: minmax(0, 1fr); gap: 1.5rem; }
  .manual-content { min-width: 0; overflow-wrap: anywhere; }
  .manual-toc { position: static; }
  .manual-content h1 { font-size: clamp(2.6rem, 15vw, 4rem); }
  .manual-table { table-layout: fixed; font-size: 0.76rem; }
  .manual-table th, .manual-table td { padding: 0.48rem; overflow-wrap: anywhere; }
}
@media (max-width: 470px) {
  .calculator-actions { grid-template-columns: 1fr; }
  .button--rail-quiet { width: 100%; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; } }
@media (forced-colors: active) {
  :root { --shadow: none; }
  .equation-rail, .segmented-control button[aria-pressed="true"] { forced-color-adjust: none; background: CanvasText; color: Canvas; }
  .chart-card, .dataset-footer, .results-placeholder { border: 2px solid CanvasText; }
  .current-badge { border-color: currentColor; }
  .field-tooltip { forced-color-adjust: none; border-color: CanvasText; background: Canvas; color: CanvasText; }
}

@media print {
  .equation-rail, .view-toolbar, .results-placeholder, .header-actions, .workspace-actions { display: none !important; }
  .workbench { display: block; }
  .workspace-panel { padding: 0; }
  .chart-card { break-inside: avoid; box-shadow: none; }
}