body.arm-page { grid-template-columns: 300px 1fr; }
:is(#panel, .pane) { background: var(--panel); border-right: 1px solid var(--line); overflow-y: auto; padding: 16px; }
:is(#panel, .pane) a { color: var(--accent); text-decoration: none; }
:is(#panel, .pane) section { margin-top: 16px; padding-top: 12px; border-top: 1px solid var(--line); }
:is(#panel, .pane) h3 { font-size: 12px; color: var(--muted); font-weight: 500; margin: 0 0 8px; }
:is(#panel, .pane) label { display: flex; justify-content: space-between; font-size: 13px; margin-top: 6px; }
:is(#panel, .pane) label span { color: var(--accent); font-variant-numeric: tabular-nums; }
:is(#panel, .pane) label.inline { display: inline-flex; gap: 4px; margin-right: 12px; cursor: pointer; }
:is(#panel, .pane) input[type=range] { width: 100%; }
:is(#panel, .pane) button { margin-top: 8px; margin-right: 6px; padding: 5px 12px; border-radius: 7px; border: 1px solid var(--line); background: var(--bg); cursor: pointer; }
.range-note { font-size: 11px; color: var(--muted); }
.dof { margin-top: 12px; font-size: 15px; }
.dof b { color: var(--accent); font-size: 20px; }
.status { margin-top: 8px; padding: 8px 10px; border-radius: 8px; font-size: 13px; font-weight: 600; }
.status.ok { background: #052e16; color: #4ade80; }
.status.warn { background: #3b2a0a; color: #fbbf24; }
.status.bad { background: #450a0a; color: #f87171; }
.readout { font-family: ui-monospace, Menlo, monospace; font-size: 15px; padding: 6px 10px; background: var(--bg); border-radius: 8px; }
.kv { display: flex; justify-content: space-between; font-size: 12px; margin-top: 6px; font-variant-numeric: tabular-nums; }
.kv span:first-child { color: var(--muted); }
.legend-list { margin-top: 10px; font-size: 11px; color: var(--muted); display: grid; gap: 3px; }
.legend-list i { display: inline-block; width: 10px; height: 10px; border-radius: 2px; margin-right: 6px; vertical-align: -1px; }
#viewport { position: relative; min-height: 0; }
.drag-hint { position: absolute; left: 12px; top: 10px; font-size: 12px; color: var(--muted); background: #0b0d11cc; padding: 8px 12px; border-radius: 8px; pointer-events: none; }
#hover { color: var(--accent); margin-top: 4px; min-height: 1em; }
@media (max-width: 900px) {
  body.arm-page { grid-template-columns: 1fr; grid-template-rows: auto 70vh auto; }
  body.arm-page main { height: 70vh; }
  #panel { border-right: 0; border-bottom: 1px solid var(--line); }
}
.explain { font-size: 12px; line-height: 1.6; margin: 0; }
.credit { font-size: 11px; color: var(--muted); margin-top: 10px; line-height: 1.5; }
.opts { display: flex; align-items: center; gap: 4px; font-size: 12px; margin-top: 6px; }
.opts > span { color: var(--muted); margin-right: 6px; }
:is(#panel, .pane) .opts label.inline { margin: 0 8px 0 0; }
.tbar { margin-top: 10px; }
.tlabel { display: flex; justify-content: space-between; font-size: 12px; }
.tlabel span:first-child { color: var(--muted); }
.tlabel span:last-child { font-variant-numeric: tabular-nums; }
.track { position: relative; height: 10px; background: var(--bg); border-radius: 5px; margin-top: 4px; overflow: hidden; }
.fill { height: 100%; width: 0; border-radius: 5px; transition: width .08s; }
.sfmark { position: absolute; top: 0; bottom: 0; width: 2px; background: #e5e7eb; opacity: .7; }
.contrib { margin-top: 10px; font-size: 12px; }
.contrib summary { cursor: pointer; color: var(--accent); }
.contrib table { width: 100%; border-collapse: collapse; margin-top: 6px; font-variant-numeric: tabular-nums; }
.contrib td, .contrib th { padding: 3px 4px; border-bottom: 1px solid var(--line); text-align: right; font-weight: normal; }
.contrib td:first-child, .contrib th:first-child { text-align: left; }
.contrib th { color: var(--muted); }
:is(#panel, .pane) select { width: 100%; margin-top: 4px; padding: 5px 8px; border-radius: 7px; border: 1px solid var(--line); background: var(--bg); color: var(--text); font: inherit; font-size: 13px; }
.note-box { margin-top: 8px; font-size: 12px; line-height: 1.6; background: #3b2a0a; border-left: 3px solid var(--test); padding: 6px 10px; border-radius: 4px; }
.seg-radio { display: flex; gap: 6px; margin-bottom: 6px; }
.seg-radio label[hidden] { display: none !important; }
.seg-radio label { flex: 1; display: flex !important; justify-content: center !important; gap: 4px; padding: 6px; border: 1px solid var(--line); border-radius: 8px; cursor: pointer; margin: 0 !important; }
.seg-radio label:has(input:checked) { border-color: var(--accent); background: #0c2a3a; }
.callout { font-size: 11px; color: #fef3c7; background: #78350fe6; border: 1px solid #f59e0b; padding: 2px 7px; border-radius: 6px; white-space: nowrap; }
.strength th { color: var(--muted); font-weight: normal; text-align: left; }
.strength td { vertical-align: top; }
.strength td:last-child { width: 80px; text-align: right; }
.track.mini { height: 6px; margin: 4px 0 2px; }
#prof-opts { display: grid; grid-template-columns: 1fr 1fr; }
#prof-opts label { white-space: nowrap; }
.st-ok { color: #4ade80; } .st-warn { color: #facc15; } .st-bad { color: #f87171; }
.bad-txt { color: #f87171; font-size: 11px; }
.rules { margin: 6px 0; padding-left: 18px; font-size: 12px; line-height: 1.7; }
.steps li { margin-bottom: 6px; } .steps li div { font-size: 11px; margin-left: 4px; }
.gs-btns { display: flex; gap: 6px; margin-top: 4px; }
.gs-btns button { flex: 1; margin: 0 !important; }
.gs-btns button.on { background: var(--accent) !important; color: #04111d; border-color: var(--accent) !important; }

/* left panel: settings only, grouped */
.why { margin-top: 10px; font-size: 12px; }
.why summary { cursor: pointer; color: var(--muted); }
.why .explain { margin-top: 6px; }

/* right panel over the 3D view: results (受力分析) */
#analysis { position: absolute; right: 12px; top: 10px; width: 380px; max-height: calc(100% - 20px); overflow-y: auto; z-index: 20;
  background: #14171df2; border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; font-size: 13px; box-shadow: 0 6px 24px #0008; }
#analysis.collapsed { width: auto; }
#analysis.collapsed #ana-body { display: none; }
.pane-head { display: flex; justify-content: space-between; align-items: center; }
.pane-head button { margin: 0 !important; padding: 2px 10px !important; font-size: 12px; }
.sum { margin-top: 8px; display: grid; gap: 4px; }
.sum-row { display: grid; grid-template-columns: 40px 1fr; align-items: center; gap: 6px; cursor: pointer; }
.sum-row > span { font-size: 12px; color: var(--muted); }
.sum-row .status { margin: 0; padding: 5px 8px; font-size: 12px; }
.tabs { display: flex; gap: 4px; margin: 10px 0 6px; flex-wrap: wrap; }
.tabs button { margin: 0 !important; padding: 4px 10px !important; font-size: 12px; }
.tabs button.on { border-color: var(--accent) !important; background: #0c2a3a !important; color: var(--accent); }
.tab-body h3 { margin-top: 4px !important; }
.show-all .tab-body { display: block !important; }
/* bottom right over the 3D view: display switches, folded by default (bug #9) */
#display { position: absolute; right: 12px; bottom: 12px; z-index: 21; border: 1px solid var(--line); border-radius: 10px;
  background: #14171df2; padding: 6px 12px; font-size: 13px; box-shadow: 0 6px 24px #0008; overflow: visible; }
#display summary { cursor: pointer; color: var(--muted); font-size: 12px; user-select: none; }
#display[open] summary { margin-bottom: 4px; }
#display[open] { width: min(330px, calc(100% - 24px)); }
.disp-body { display: grid; grid-template-columns: 1fr 1fr; column-gap: 8px; }
.disp-body > div { grid-column: 1 / -1; }
#display label.inline { display: flex; justify-content: flex-start; gap: 4px; margin: 4px 0 0; font-size: 12px; }
#display button { margin-top: 6px; padding: 4px 10px; font-size: 12px; }
@media (max-width: 900px) { #analysis { position: static; width: auto; max-height: none; margin: 12px; } }

/* pop-up: download / 3D printing (bug #2) */
.modal { position: fixed; inset: 0; z-index: 50; background: #000a; display: flex; align-items: center; justify-content: center; padding: 24px; }
.modal[hidden] { display: none; }
.modal-card { width: min(1100px, 100%); max-height: 100%; overflow-y: auto; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 14px 18px; font-size: 13px; }
.modal-body { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 8px; }
@media (max-width: 900px) { .modal-body { grid-template-columns: 1fr; } }
.show-all .modal { display: block !important; position: static; }
button.primary { width: 100%; background: var(--accent) !important; color: #04111d; border-color: var(--accent) !important; font-weight: 600; }
.float-btn { position: absolute; left: 50%; bottom: 16px; transform: translateX(-50%); z-index: 20; padding: 8px 18px; border-radius: 8px; border: 1px solid var(--accent); background: #0c2a3a; color: var(--accent); font-weight: 600; cursor: pointer; }