:root { --accent: var(--teal); --accent-rgb: var(--teal-rgb); }
* { box-sizing: border-box; }
[hidden] { display: none !important; }
button, input { font: inherit; }
button { border: 0; background: none; color: inherit; cursor: pointer; -webkit-tap-highlight-color: transparent; }
input[type="range"], summary { cursor: pointer; }
:is(button, a, input, summary, [tabindex]):focus-visible { outline: 2px solid var(--focus-ring); outline-offset: 3px; border-radius: var(--radius-small); }
h1, h2, h3, p { margin-top: 0; }
.dh-shell { width: 100%; }
.dh-shell .model-page-content { scrollbar-gutter: stable both-edges; }

/* Common actions surround the model; only the data sheet opens on demand. */
.dh-workspace.model-stage {
  --model-width: 33.333333vw;
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--model-width) minmax(0, 1fr);
  grid-template-rows: max(64px, calc(var(--stage-height) * .25 - var(--stage-top-space))) var(--model-height) auto auto;
  grid-template-areas: "presets presets presets" "joints model parameters" "actions editor views" "data data data";
  align-items: center;
  align-content: start;
  column-gap: clamp(16px, 2.3vw, 36px);
  min-height: 0;
  padding: 0 28px 24px;
}
.dh-workspace.model-stage:has(.model-stage__panel:not([hidden])) { padding-top: 0; padding-bottom: 24px; }
.dh-presets { grid-area: presets; display: flex; justify-content: center; flex-wrap: wrap; gap: 6px 20px; align-self: end; padding-bottom: 10px; }
.dh-presets button { min-height: 44px; padding: 8px 6px; color: var(--muted); font-size: 13px; }
.dh-presets button[aria-pressed="true"] { color: var(--ink); font-weight: 600; }
.dh-presets button:hover { color: var(--accent); }
.dh-workspace .dh-visual { grid-area: model; position: relative; inset: auto; width: 100%; height: var(--model-height); min-width: 0; transform: none; }
.dh-scene { height: 100%; }
#dhScene { display: block; width: 100%; height: 100%; touch-action: pan-y; user-select: none; cursor: grab; }
#dhScene.is-dragging { cursor: grabbing; }
#dhDrawing { font-family: inherit; }
.dh-joint:hover > circle:nth-child(2), .dh-joint:focus-visible > circle:nth-child(2) { stroke: var(--accent); stroke-width: 4; }
.dh-joint:focus-visible { outline: none; }

.dh-joint-tabs { grid-area: joints; display: flex; flex-direction: column; justify-self: end; gap: 6px; }
.dh-joint-tabs button { display: flex; align-items: center; gap: 12px; min-width: 70px; min-height: 44px; padding: 8px 12px; color: var(--muted); font-size: 14px; }
.dh-joint-tabs button::before { content: ""; width: 5px; height: 5px; border-radius: 50%; background: currentColor; opacity: .3; }
.dh-joint-tabs button[aria-pressed="true"], .dh-parameter-tabs button[aria-pressed="true"] { color: var(--accent); }
.dh-joint-tabs button[aria-pressed="true"]::before { opacity: 1; }
.dh-joint-tabs button:hover, .dh-parameter-tabs button:hover { color: var(--ink); }
.dh-parameter-tabs { grid-area: parameters; display: grid; gap: 6px; justify-self: start; width: min(224px, 100%); }
.dh-parameter-tabs button { display: grid; grid-template-columns: 22px minmax(0, 1fr) auto; align-items: baseline; gap: 10px; min-height: 44px; padding: 9px 4px; color: var(--muted); text-align: left; }
.dh-parameter-tabs b { font: 400 22px Georgia, serif; text-align: center; }
.dh-parameter-tabs span { font-size: 12px; }
.dh-parameter-value { white-space: nowrap; font-variant-numeric: tabular-nums; }

.dh-editor { grid-area: editor; min-width: 0; padding-top: 8px; }
.dh-editor-heading { display: flex; align-items: center; gap: 10px; min-height: 36px; }
.dh-editor-heading label { font-size: 14px; font-weight: 500; white-space: nowrap; }
.dh-edit-kind { color: var(--muted); font-size: 11px; }
.dh-number-wrap { display: flex; align-items: baseline; gap: 4px; margin-left: auto; font-size: 12px; color: var(--muted); }
.dh-number-wrap input { width: 64px; padding: 5px 2px; border: 0; border-bottom: 1px solid var(--line); border-radius: 0; background: transparent; color: var(--ink); font-size: 14px; text-align: right; font-variant-numeric: tabular-nums; appearance: textfield; -moz-appearance: textfield; }
.dh-number-wrap input::-webkit-inner-spin-button, .dh-number-wrap input::-webkit-outer-spin-button { -webkit-appearance: none; margin: 0; }
.dh-number-wrap input:hover, .dh-number-wrap input:focus { border-color: var(--accent); }
.dh-editor input[type="range"] { display: block; width: 100%; height: 32px; margin: 2px 0; padding: 0; appearance: none; background: transparent; accent-color: var(--accent); }
.dh-editor input[type="range"]::-webkit-slider-runnable-track { height: 2px; background: var(--line-strong); border-radius: 1px; }
.dh-editor input[type="range"]::-webkit-slider-thumb { appearance: none; width: 12px; height: 12px; margin-top: -5px; border-radius: 50%; background: var(--accent); }
.dh-editor input[type="range"]::-moz-range-track { height: 2px; background: var(--line-strong); }
.dh-editor input[type="range"]::-moz-range-thumb { width: 12px; height: 12px; border: 0; border-radius: 50%; background: var(--accent); }
.dh-parameter-hint { min-height: 20px; margin: 2px 0 0; color: var(--muted); font-size: 12px; line-height: 1.7; text-align: center; }

.dh-actions { grid-area: actions; display: flex; justify-self: end; gap: 10px; }
.dh-icon { display: grid; place-items: center; flex: 0 0 44px; width: 44px; height: 44px; padding: 10px; color: var(--muted); }
.dh-icon svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; transition: transform 180ms ease; }
.dh-icon:hover:not(:disabled) { color: var(--ink); }
.dh-icon:hover:not(:disabled) svg { transform: scale(1.08); }
.dh-icon[aria-pressed="true"] { color: var(--accent); }
.dh-icon:disabled { opacity: .3; cursor: default; }
.dh-view-controls { grid-area: views; display: flex; flex-wrap: wrap; align-items: center; justify-self: start; max-width: 300px; column-gap: 8px; }
.dh-view-buttons { display: flex; gap: 4px; }
.dh-view-buttons button, .dh-data-entry { min-height: 44px; padding: 8px 7px; color: var(--muted); font-size: 12px; }
.dh-view-buttons button[aria-pressed="true"], .dh-data-entry[aria-expanded="true"] { color: var(--accent); }
.dh-view-buttons button:hover, .dh-data-entry:hover { color: var(--ink); }
.dh-zoom { display: flex; align-items: center; color: var(--muted); }
.dh-zoom output { min-width: 38px; font-size: 11px; text-align: center; font-variant-numeric: tabular-nums; }
.dh-data-entry::before { display: none; }

.dh-workspace .dh-observations { grid-area: data; position: static; width: min(720px, 100%); max-height: none; min-width: 0; margin: 28px auto 0; padding: 20px 0 0; overflow: visible; scrollbar-gutter: auto; border: 0; border-top: 1px solid var(--line); border-radius: 0; background: transparent; }
.dh-observations .model-stage__panel-heading h2 { font-size: 15px; font-weight: 500; margin: 0; }
.dh-position { padding: 6px 0 22px; }
.dh-position > div { display: flex; align-items: baseline; justify-content: space-between; gap: 6px; }
.dh-caption { font-size: 12px; color: var(--muted); }
.dh-position small { font-size: 10px; color: var(--muted); }
.dh-position dl { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 16px 0 0; }
.dh-position dl > div { display: flex; align-items: baseline; gap: 10px; }
.dh-position dt { font-size: 12px; color: var(--muted); }
.dh-position dd { margin: 0; font: 500 18px ui-monospace, Consolas, monospace; font-variant-numeric: tabular-nums; }
.dh-table-section { padding-top: 18px; border-top: 1px solid var(--line); }
.dh-section-heading { display: flex; flex-wrap: wrap; align-items: baseline; gap: 8px 20px; margin-bottom: 12px; }
.dh-section-heading h2 { font-size: 15px; font-weight: 500; margin: 0; }
.dh-section-heading > p { color: var(--muted); font-size: 11px; margin: 0; line-height: 1.8; }
.dh-variable-key { display: inline-block; width: 12px; height: 12px; border-radius: 3px; background: var(--accent-soft); margin-right: 5px; vertical-align: middle; }
.dh-table-scroll { overflow-x: auto; }
.dh-table { border-collapse: collapse; width: 100%; min-width: 490px; text-align: center; font-size: 13px; }
.dh-table th { padding: 13px 10px; font-weight: 500; color: var(--muted); }
.dh-table small { font-size: 10px; font-weight: 400; margin-left: 4px; color: var(--muted); }
.dh-table td, .dh-table tbody th { border-top: 1px solid var(--line); padding: 7px 10px; }
.dh-table button { min-width: 66px; min-height: 44px; padding: 6px 12px; border-radius: var(--radius-small); font-family: ui-monospace, Consolas, monospace; font-variant-numeric: tabular-nums; }
.dh-table .is-variable { background: var(--accent-soft); color: var(--accent); }
.dh-table button.is-selected { outline: 1.5px solid var(--accent); outline-offset: -1.5px; }
.dh-table tr.is-selected > th { color: var(--accent); font-weight: 600; }
.dh-table .dh-type { font-size: 11px; color: var(--muted); }
.dh-matrix-section { margin-top: 22px; padding: 8px 0 18px; border-block: 1px solid var(--line); }
.dh-matrix-section > summary { display: flex; align-items: center; justify-content: space-between; list-style: none; min-height: 44px; }
.dh-matrix-section > summary::-webkit-details-marker { display: none; }
.dh-matrix-section > summary strong { font-size: 15px; font-weight: 500; }
.dh-details-icon { font-size: 22px; color: var(--muted); padding: 10px; transition: transform 180ms ease; }
.dh-matrix-section[open] .dh-details-icon { transform: rotate(45deg); }
.dh-matrix-content { padding-top: 14px; }
.dh-equation { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; font: 13px/1.9 ui-monospace, Consolas, monospace; }
.dh-matrix-switch { display: flex; flex-wrap: wrap; gap: 7px; margin: 16px 0; }
.dh-matrix-switch button { min-height: 44px; padding: 8px 12px; color: var(--muted); font-size: 12px; }
.dh-matrix-switch button[aria-pressed="true"] { color: var(--accent); }
.dh-matrix-layout { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 24px; align-items: center; margin: 18px 0; }
.dh-matrix-brackets { padding: 8px; border-inline: 2px solid var(--line-strong); border-radius: var(--radius-control); overflow-x: auto; }
.dh-matrix { width: 100%; min-width: 285px; border-spacing: 5px; font: 12px ui-monospace, Consolas, monospace; text-align: right; }
.dh-matrix caption { font: 11px var(--font-sans); color: var(--muted); padding: 0 0 9px; text-align: center; }
.dh-matrix td { padding: 7px 4px; border-radius: var(--radius-small); background: var(--surface-muted); font-variant-numeric: tabular-nums; }
.dh-matrix tr:not(:last-child) td:last-child { background: var(--accent-soft); color: var(--accent); }
.dh-matrix tr:last-child td { background: transparent; color: var(--muted); }
.dh-matrix-layout h3 { font-size: 14px; font-weight: 500; }
.dh-matrix-layout p, .dh-formula-details p { font-size: 12px; line-height: 1.9; color: var(--muted); }
.dh-formula-details summary { min-height: 44px; padding: 10px 0; color: var(--muted); font-size: 12px; }
.dh-symbolic { overflow-x: auto; padding: 12px; background: var(--surface-muted); border-radius: var(--radius-control); }
.dh-symbolic pre { margin: 0; font: 13px/1.9 ui-monospace, Consolas, monospace; }
.dh-scope-note { font-size: 11px; line-height: 1.9; color: var(--muted); margin: 16px 0 0; }
.dh-noscript { max-width: 680px; margin: 0 auto; padding: 28px; line-height: 1.8; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }

@media (max-width: 800px) {
  .dh-workspace.model-stage {
    --model-height: clamp(260px, 43svh, 380px);
    grid-template-columns: auto minmax(0, 1fr);
    grid-template-rows: auto var(--model-height) auto auto auto auto auto;
    grid-template-areas: "presets presets" "model model" "joints joints" "parameters parameters" "editor editor" "actions views" "data data";
    column-gap: 12px;
    row-gap: 10px;
    padding-inline: max(18px, env(safe-area-inset-left)) max(18px, env(safe-area-inset-right));
  }
  .dh-presets { gap: 4px 12px; padding-bottom: 0; }
  .dh-workspace .dh-visual { width: min(520px, 100%); justify-self: center; }
  .dh-joint-tabs { flex-direction: row; justify-self: center; gap: 10px; }
  .dh-joint-tabs button { min-width: 64px; }
  .dh-parameter-tabs { grid-template-columns: repeat(4, minmax(0, 1fr)); width: min(440px, 100%); justify-self: center; gap: 6px; }
  .dh-parameter-tabs button { grid-template-columns: auto auto; justify-content: center; gap: 4px 6px; text-align: center; }
  .dh-parameter-tabs .dh-parameter-value { grid-column: 1 / -1; font-size: 11px; }
  .dh-editor { width: min(440px, 100%); justify-self: center; padding-top: 0; }
  .dh-actions { justify-self: end; gap: 2px; }
  .dh-view-controls { justify-self: start; column-gap: 4px; }
  .dh-view-buttons button { padding-inline: 5px; }
  .dh-workspace .dh-observations { margin-top: 12px; }
  .dh-matrix-layout { grid-template-columns: minmax(0, 1fr); gap: 14px; }
}
@media (max-width: 400px) {
  .dh-parameter-tabs button { grid-template-columns: minmax(0, 1fr); }
  .dh-position dl > div { display: block; }
  .dh-position dd { margin-top: 5px; font-size: 16px; }
  .dh-view-controls { row-gap: 0; }
}
@media (prefers-reduced-motion: reduce) {
  .dh-icon svg, .dh-details-icon { transition: none; }
  .dh-icon:hover:not(:disabled) svg { transform: none; }
}