solar.css

/* Chapter 01 components. Loaded after styles.css and theme.css. */
@layer components {
  :root {
    --alt: light-dark(#2479ad, #8bcfff);
    --azi: light-dark(#007c9a, #6bd8f0);
    --third: light-dark(#6a4fb3, #c3b2ff);
    --calc-surface: light-dark(#f6f9fb, #25282c);
  }
  .sym { font-weight: 650; letter-spacing: .02em; color: var(--ink); }
  .sym.alt { color: var(--alt); }
  .sym.azi { color: var(--azi); }
  .sym.third { color: var(--third); }

  /* Inputs directly below each interactive drawing */
  .diagram-inputs { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 12px 22px; align-items: start;
    margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); font-size: 11px; }
  .inputs-label { grid-column: 1 / -1; margin: 0 0 -4px; font-size: 9px; letter-spacing: .1em; color: var(--muted); font-weight: 650; }
  .diagram-inputs label { font-size: 10.5px; font-weight: 650; color: var(--ink); letter-spacing: .02em; }
  .diagram-inputs .control-row { margin-top: 0; }
  .diagram-inputs input[type=range] { margin-top: 2px; }
  .diagram-inputs select { width: 100%; min-height: 32px; padding: 5px 8px; font-size: 11.5px; margin: 4px 0 0; }
  .diagram-inputs .input-preset { min-height: 28px; font-size: 10.5px; color: var(--muted); }
  .diagram-inputs .segmented { margin: 4px 0 0; }
  .diagram-inputs .segmented button { min-height: 24px; padding: 3px 2px; font-size: 9.5px; }
  .diagram-inputs .input-check { align-self: center; }
  .diagram-inputs .input-check .check-label { margin: 0; }
  .diagram-inputs .input-wide { grid-column: 1 / -1; }
  .diagram-inputs .input-wide .small-label { margin: 0 0 4px; }
  .diagram-inputs output { font-variant-numeric: tabular-nums; }
  .play-toggle { font-size: 10px; margin-top: 4px; color: var(--accent); font-weight: 600; }
  /* Interactive panels are tagged; numbered figures are static. */
  .lab.is-interactive .canvas-heading > .small-label:first-child::before { content: "INTERACTIVE"; display: inline-block; margin-right: 8px; padding: 1px 6px; border: 1px solid var(--accent); border-radius: 3px; color: var(--accent); font-weight: 700; letter-spacing: .08em; }
  .lab.is-interactive .canvas-heading-next > .small-label:first-child::before { content: none; }
  .canvas-heading-next { margin-top: 18px; padding-top: 14px; border-top: 1px dashed var(--line); }
  /* Inputs stay directly under the drawing, whatever the height of the side panel. */
  .lab.is-interactive .lab-canvas { justify-content: flex-start; }
  .lab-calc .calc { max-width: 760px; }

  /* Dashboard: several drawings driven by one input strip, which stays in view while the card scrolls past. */
  .lab-dashboard { overflow: clip; }
  .dash-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px 26px; margin-top: 6px; }
  .dash-panel { min-width: 0; padding-top: 12px; border-top: 1px dashed var(--line); }
  .lab.is-interactive .dash-panel .canvas-heading > .small-label:first-child::before { content: none; }
  .dash-calc { grid-column: 1 / -1; }
  /* Section 03 time-zone dashboard: city picker on top, drawings stacked, values at the side. */
  .lab-timezones .diagram-inputs { display: flex; flex-wrap: wrap; align-items: end; gap: 8px 18px; margin: 8px 0 4px; }
  .lab-timezones .diagram-inputs .inputs-label { display: none; }
  .lab-timezones .diagram-inputs .input:first-of-type { flex: 0 1 230px; }
  .lab-timezones .diagram-inputs .input-wide { flex: 1 1 360px; }
  .lab-timezones .diagram-inputs .segmented-wrap { flex-wrap: nowrap; }
  .lab-timezones .diagram-inputs .segmented-wrap button { flex: 1 1 auto; padding: 3px 6px; }
  .lab-timezones .lab-controls .control-kicker { margin-bottom: 8px; }
  .lab-timezones .tz-key { margin: 0; }
  .tz-panel { min-width: 0; padding-top: 8px; margin-top: 8px; border-top: 1px dashed var(--line); }
  .lab.is-interactive .tz-panel .canvas-heading > .small-label:first-child::before { content: none; }
  .tz-map svg { cursor: crosshair; }
  .lab-timezones .control-note p { margin: 0 0 8px; }
  .dash-calc .calc { max-width: 620px; }
  .lab-dashboard .diagram-inputs { position: sticky; bottom: 0; z-index: 2; margin: 14px -22px -13px; padding: 12px 22px 13px; background: var(--sage); box-shadow: 0 -6px 12px -10px rgb(0 0 0 / .35); }

  /* Text blocks */
  .precedents { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: 18px 0 6px; margin: 6px 0 26px; }
  .precedents h3 { font-size: 14px; margin-bottom: 4px; }
  .precedents p { font-size: 12px; line-height: 1.6; color: var(--body); }
  .facts { max-width: 820px; font-size: 14px; padding-left: 20px; margin: 0 0 24px; }
  .facts li { padding-left: 4px; margin-bottom: 7px; }
  .defs { display: grid; gap: 0; max-width: 860px; margin: 0 0 22px; border-top: 1px solid var(--line); }
  .defs > div { display: grid; grid-template-columns: 230px 1fr; gap: 18px; padding: 11px 0; border-bottom: 1px solid var(--line); }
  .defs dt { font-size: 13px; font-weight: 650; color: var(--ink); }
  .defs dd { margin: 0; font-size: 13px; line-height: 1.65; }
  h3.sub { font-size: 18px; margin: 36px 0 12px; }
  .callout { display: grid; grid-template-columns: 100px 1fr; gap: 20px; margin: 26px 0; padding: 16px 18px; border-left: 3px solid var(--accent); background: var(--sage); }
  .callout > span { font-size: 9px; font-weight: 700; letter-spacing: .1em; color: var(--accent); padding-top: 4px; }
  .callout p { margin: 0; font-size: 13px; max-width: 820px; }
  .table-wrap { overflow-x: auto; margin: 10px 0 18px; }
  .nomenclature { border-collapse: collapse; width: 100%; max-width: 980px; font-size: 12px; line-height: 1.5; }
  .nomenclature caption { text-align: left; font-size: 10px; letter-spacing: .1em; font-weight: 650; color: var(--muted); padding-bottom: 8px; text-transform: uppercase; }
  .nomenclature th, .nomenclature td { text-align: left; vertical-align: top; padding: 7px 12px 7px 0; border-bottom: 1px solid var(--line); }
  .nomenclature thead th { font-size: 10px; color: var(--muted); font-weight: 650; letter-spacing: .05em; }
  .nomenclature tbody th { color: var(--ink); font-weight: 650; white-space: nowrap; }
  .nomenclature td:nth-child(2) { font-style: italic; white-space: nowrap; }
  .nomenclature.compact { max-width: 720px; }
  .nomenclature.compact td:nth-child(2) { font-style: normal; font-variant-numeric: tabular-nums; }

  /* Equations */
  .eq { display: flex; justify-content: space-between; align-items: center; gap: 20px; max-width: 980px; margin: 14px 0; padding: 12px 16px; border: 1px solid var(--line); border-radius: 5px; background: var(--panel); }
  .eq-math { display: flex; flex-direction: column; gap: 8px; min-width: 0; max-width: 100%; color: var(--ink); }
  .eq-line { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 14px; max-width: 100%; overflow-x: auto; overflow-y: hidden; padding-block: 2px; }
  .eq-math math { font-family: "STIX Two Math", "Cambria Math", "Latin Modern Math", math; font-size: 19px; math-style: normal; }
  .eq-math math .sym { font-weight: 400; letter-spacing: 0; }
  .eq-label, .eq-note, .eq-unit { font-size: 12px; line-height: 1.5; color: var(--muted); }
  .eq-label { flex-basis: 100%; letter-spacing: .02em; }
  .eq-unit::before { content: "["; } .eq-unit::after { content: "]"; }
  .eq-n { font-size: 12px; color: var(--muted); white-space: nowrap; }
  .eq:target { border-color: var(--accent); }

  /* Calculation panels */
  .calc { font-size: 11.5px; line-height: 1.5; font-variant-numeric: tabular-nums; }
  .calc hr { border: 0; border-top: 1px solid var(--line); margin: 6px 0; }
  .calc-row { display: grid; grid-template-columns: 74px minmax(0, 1fr) auto; gap: 8px; padding: 4px 0; align-items: baseline; }
  .calc-k { font-weight: 650; color: var(--ink); }
  .calc-e { color: var(--muted); overflow-wrap: anywhere; }
  .calc-v { color: var(--ink); text-align: right; white-space: nowrap; }
  .calc-key .calc-v { color: var(--accent); font-weight: 700; }
  .calc-warn .calc-e { color: var(--red); }
  .calc-wide, .calc-inline { max-width: 980px; margin: 14px 0; padding: 12px 16px; border: 1px solid var(--line); border-radius: 5px; background: var(--calc-surface); }
  .calc-wide .calc-row, .calc-inline .calc-row { grid-template-columns: 140px minmax(0, 1fr) auto; }
  .lab-controls .calc { margin-top: 12px; }
  .clock-lab .calc { padding-left: 25px; border-left: 1px solid var(--line); }
  .clock-inputs input[type=number] { width: 100%; min-height: 44px; padding: 10px 12px; border: 1px solid var(--line); border-radius: 4px; background: var(--panel); color: var(--ink); }

  /* Drawings */
  .diagram-host svg, .fig svg { width: 100%; height: auto; display: block; }
  /* One line weight and type size across figures drawn at different scales (src/svg.js LINE, TYPE).
     Strokes keep their width in screen pixels; text takes its size from --fs, corrected by --u
     (src/diagram-scale.js). Hatch tiles scale with the drawing; the sundial stays true to size. */
  svg.diagram:not(.exact) :is(line, polyline, polygon, path, circle, rect, ellipse, text):not(pattern *) { vector-effect: non-scaling-stroke; }
  svg.diagram text[style*="--fs"] { font-size: calc(var(--fs) * var(--u, 1) * 1px); }
  .diagram-host.narrow svg { max-width: 420px; margin: 0 auto; }
  #d-sundial svg { max-width: 860px; margin: 0 auto; }
  .lab-wide { grid-template-columns: 1fr; }
  .lab-wide .lab-canvas { padding-bottom: 16px; }
  .steps { font-size: 12px; padding-left: 18px; margin: 0 0 10px; }
  .steps li { margin-bottom: 5px; }
  .segmented-wrap { flex-wrap: wrap; }
  .segmented-wrap button { flex: 1 1 45%; }
  .fig { margin: 26px 0; max-width: 1100px; }
  .fig-plate { background: var(--sage); border: 1px solid var(--line); border-radius: 7px; padding: 16px 18px; }
  .fig figcaption { display: flex; justify-content: space-between; gap: 18px; font-size: 11px; color: var(--muted); padding-top: 8px; line-height: 1.6; }
  .fig figcaption strong { color: var(--ink); font-weight: 650; }
  .fig figcaption a { white-space: nowrap; text-decoration: none; color: var(--accent); font-weight: 600; }
  .math-details .fig { margin: 8px 0; }
  .mask-year { margin-top: 18px; font-size: 10px; font-variant-numeric: tabular-nums; }
  .bar-row { display: grid; grid-template-columns: 26px 1fr 28px; gap: 6px; align-items: center; margin: 2px 0; }
  .bar-row > span:last-child { text-align: right; }
  .bar { position: relative; height: 7px; background: var(--line); border-radius: 2px; overflow: hidden; }
  .bar i, .bar b { position: absolute; inset: 0 auto 0 0; }
  .bar i { background: var(--accent-soft); }
  .bar b { background: var(--accent); }
  .fig-list { columns: 2; column-gap: 40px; font-size: 12px; padding-left: 18px; }
  .fig-list li { margin-bottom: 6px; break-inside: avoid; }
  .fig-list a { color: var(--accent); text-decoration: none; font-weight: 600; }
  .fig-list span { color: var(--muted); }
  /* Figure 1: the site is dragged on the world map or typed as LAT and LONG. */
  .coord-stage { position: relative; }
  .coord-hit { position: absolute; cursor: crosshair; touch-action: none; }
  /* Figure 1 spans the full width of a lab (drawing plus calculation panel), not the 1100px figure cap. */
  #fig-coordinates { max-width: none; }
  #fig-coordinates .fig-plate { padding: 10px 12px; }
  #fig-coordinates .fig-plate:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
  /* One line of inputs above the plate: location, LAT, LONG. */
  #fig-coordinates .diagram-inputs { grid-template-columns: minmax(220px, 1.6fr) repeat(2, minmax(160px, 1fr)); align-items: end; margin: 0 0 10px; padding-top: 0; border-top: 0; }
  #fig-coordinates .inputs-label { display: none; }
  #fig-coordinates .diagram-inputs .input-preset { color: var(--ink); }
  /* The location dropdown, the number fields and the hemisphere selects share one height. */
  #fig-coordinates .diagram-inputs :is(select, input) { box-sizing: border-box; height: 34px; min-height: 0; margin: 0; padding: 0 8px; font-size: 12px; line-height: 1; }
  #fig-coordinates .diagram-inputs .input > select { margin-top: 4px; }
  @media (max-width: 700px) { #fig-coordinates .diagram-inputs { grid-template-columns: 1fr; } }
  #fig-coordinates figcaption .quiet-button { font-size: 11px; }
  .coord-entry { display: flex; gap: 6px; margin-top: 4px; }
  .coord-entry input { flex: 1; min-width: 0; min-height: 32px; padding: 5px 8px; border: 1px solid var(--line); border-radius: 4px; background: var(--panel); color: var(--ink); font-size: 12px; font-variant-numeric: tabular-nums; }
  .coord-entry input[aria-invalid] { border-color: var(--red); }
  .diagram-inputs .coord-entry select { width: auto; margin: 0; }

  /* Self-test */
  .quiz-ref { clear: both; font-size: 10px; letter-spacing: .06em; color: var(--muted); margin: 0 0 10px; }
  .quiz-numeric { display: flex; align-items: center; gap: 12px; }
  .quiz-numeric input { width: 150px; min-height: 40px; padding: 8px 10px; font-size: 14px; border: 1px solid var(--line); border-radius: 4px; background: var(--panel); color: var(--ink); font-variant-numeric: tabular-nums; }
  .quiz-numeric .unit { font-size: 13px; color: var(--muted); min-width: 30px; }
  .quiz-feedback { display: block; margin-top: 12px; font-size: 12px; }
  .quiz-feedback:empty { display: none; }
  .quiz-feedback p { margin-bottom: 6px; }
  .quiz-feedback.correct { color: var(--body); border-left: 3px solid var(--accent); padding-left: 12px; }
  .quiz-feedback.correct strong { color: var(--accent); }
  .quiz-feedback.incorrect { color: var(--body); border-left: 3px solid var(--red); padding-left: 12px; }
  .quiz-feedback.incorrect strong { color: var(--red); }
  .quiz-feedback.empty { color: var(--muted); }
  .quiz-eq { font-variant-numeric: tabular-nums; color: var(--ink); background: var(--calc-surface); padding: 6px 10px; border-radius: 3px; display: inline-block; margin: 2px 0 6px; }
}

@layer responsive {
  @media (max-width: 1150px) {
    .precedents { grid-template-columns: 1fr 1fr; }
    .lab-dashboard .diagram-inputs { margin: 14px -15px -12px; padding: 12px 15px; }
  }
  @media (max-width: 1000px) {
    .dash-grid { grid-template-columns: 1fr; }
  }
  @media (max-width: 650px) {
    .diagram-inputs { grid-template-columns: 1fr 1fr; }
    .defs > div { grid-template-columns: 1fr; gap: 3px; }
    .callout { grid-template-columns: 1fr; gap: 6px; }
    .eq { flex-direction: column; align-items: flex-start; gap: 4px; padding: 10px 12px; }
    .eq-math { align-self: stretch; }
    .eq-math math { font-size: 16px; }
    .calc-wide .calc-row, .calc-inline .calc-row, .calc-row { grid-template-columns: 1fr auto; }
    .calc-e { grid-column: 1 / -1; order: 3; }
    .clock-lab .calc { padding: 18px 0 0; border-left: 0; border-top: 1px solid var(--line); }
    .clock-inputs { grid-template-columns: 1fr 1fr; }
    .fig figcaption { flex-direction: column; gap: 4px; }
    .fig-list { columns: 1; }
    .precedents { grid-template-columns: 1fr; gap: 10px; }
  }
}
@layer print {
  @media print { .diagram-inputs, .quiet-button, .play-toggle { display: none !important; } }
}