:root{
  --bg:#DCE1DE; --rail:#EEF1EF; --ink:#1B2321; --muted:#56625E; --rule:#C3CBC7;
  --accent:#3F6FB5; --accent-ink:#FFFFFF; --field:#FFFFFF; --scene:#DCE1DE; --box:#7F8C87;
  --card:rgba(238,241,239,.94); --fault:#C2410C; --fault-ink:#8B0000;
  color-scheme:light;
  box-sizing:border-box;
  padding-top:env(safe-area-inset-top,0px);
  padding-bottom:env(safe-area-inset-bottom,0px);
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --bg:#141918; --rail:#1B211F; --ink:#E3E9E6; --muted:#9AA7A2; --rule:#34403C;
    --accent:#86A9E3; --accent-ink:#0E1624; --field:#232B29; --scene:#161C1B; --box:#6E7D78;
    --card:rgba(27,33,31,.94); --fault:#FF8A5B; --fault-ink:#8B0000;
    color-scheme:dark;
  }
}
:root[data-theme="dark"]{
  --bg:#141918; --rail:#1B211F; --ink:#E3E9E6; --muted:#9AA7A2; --rule:#34403C;
  --accent:#86A9E3; --accent-ink:#0E1624; --field:#232B29; --scene:#161C1B; --box:#6E7D78;
  --card:rgba(27,33,31,.94); --fault:#FF8A5B; --fault-ink:#8B0000;
  color-scheme:dark;
}
*,*::before,*::after{box-sizing:inherit}
html{height:100%;scroll-padding-top:env(safe-area-inset-top,0px)}
body{margin:0;height:100%;background:var(--bg);color:var(--ink);
  font-family:'Barlow',system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;font-size:14px;line-height:1.45;}
.app{display:grid;grid-template-columns:318px minmax(0,1fr);height:100%}
.rail{background:var(--rail);border-right:1px solid var(--rule);overflow-y:auto;padding:22px 20px 28px}
.stage{position:relative;overflow:hidden;min-width:0;background:var(--scene)}
#gl{position:absolute;inset:0;width:100%;height:100%;display:block;touch-action:none}
h1{font-size:21px;line-height:1.2;font-weight:600;margin:0 0 6px;letter-spacing:-.005em}
.lede{color:var(--muted);margin:0 0 4px;font-size:13.5px}
section.group{border-top:1px solid var(--rule);padding-top:14px;margin-top:16px}
h2{font-size:14.5px;font-weight:600;margin:0 0 8px}
.row{display:flex;align-items:center;gap:10px;margin:10px 0 4px}
.row label{flex:1}
.num{font-family:'Barlow Semi Condensed','Barlow',system-ui,sans-serif;font-variant-numeric:tabular-nums;font-weight:500}
.btn{font:inherit;font-weight:500;border:1px solid var(--rule);background:var(--field);color:var(--ink);
  padding:7px 11px;border-radius:5px;cursor:pointer}
.btn:hover{border-color:var(--muted)}
.btn.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent);width:100%;padding:9px 12px}
.btn.small{padding:3px 9px;font-size:12.5px}
.btn:focus-visible,.seg button:focus-visible,input:focus-visible,summary:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.seg{display:flex;border:1px solid var(--rule);border-radius:5px;overflow:hidden;background:var(--field)}
.seg button{flex:1;font:inherit;font-size:13px;border:0;background:transparent;color:var(--ink);padding:6px 4px;cursor:pointer}
.seg button+button{border-left:1px solid var(--rule)}
.seg button[aria-pressed="true"]{background:var(--accent);color:var(--accent-ink)}
.views{display:grid;grid-template-columns:1fr 1fr;gap:6px}
input[type=range]{width:100%;accent-color:var(--accent)}
input[type=checkbox]{accent-color:var(--accent);width:15px;height:15px;margin:0}
.check{display:flex;gap:9px;align-items:flex-start;margin:7px 0;cursor:pointer}
.check input{margin-top:3px}
.sub{color:var(--muted);font-size:12.5px}
table.facts{width:100%;border-collapse:collapse;font-size:13px;margin-top:10px}
table.facts td{padding:3px 0;vertical-align:top}
table.facts td+td{text-align:right;white-space:nowrap;padding-left:8px}
.key{display:grid;grid-template-columns:18px 1fr;gap:6px 8px;align-items:start;font-size:12.5px;margin:8px 0 4px}
.sw{width:18px;height:12px;border:1px solid rgba(0,0,0,.25);margin-top:3px;display:inline-block;flex:none}
details{margin-top:6px}
summary{cursor:pointer;font-weight:500}
.note{font-size:12.5px;color:var(--muted);margin-top:16px;border-top:1px solid var(--rule);padding-top:12px}
.note p{margin:0 0 6px}
.card{position:absolute;background:var(--card);border:1px solid var(--rule);border-radius:6px;
  backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px)}
#readout{left:14px;bottom:14px;width:min(340px,calc(100% - 28px));padding:10px 13px;font-size:13px}
#readout .t,#logwrap .t{font-weight:600;margin-bottom:3px}
#readout .ln,#logwrap .ln{display:flex;justify-content:space-between;gap:12px}
#readout .ln span:first-child,#logwrap .ln span:first-child{color:var(--muted)}
.unit{display:flex;gap:8px;align-items:flex-start;margin-top:5px}
#logwrap{right:14px;top:84px;width:min(310px,calc(100% - 28px));max-height:calc(100% - 150px);overflow:auto;padding:11px 13px;font-size:13px}
.logbody{display:grid;grid-template-columns:auto 1fr;gap:12px;margin-top:8px}
#logcv{display:block}
ol.iv{list-style:none;margin:0;padding:0;font-size:12.5px}
ol.iv li{display:grid;grid-template-columns:12px 1fr;gap:6px;padding:2px 0;border-bottom:1px solid var(--rule)}
ol.iv li:last-child{border-bottom:0}
ol.iv .d{color:var(--muted)}
#compass{right:14px;top:14px;width:58px;height:58px;padding:4px}
#hint{right:14px;bottom:14px;padding:7px 10px;font-size:12px;color:var(--muted);max-width:280px}
#logwrap:not([hidden]) ~ #hint{display:none}
.tick{position:absolute;font-size:11.5px;color:var(--muted);padding:0 6px;pointer-events:none;white-space:nowrap}
#loading{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;color:var(--muted);font-size:14px}
#secCard{left:14px;right:14px;bottom:14px;padding:9px 13px 10px;font-size:13px}
.sechead{display:flex;justify-content:space-between;align-items:baseline;gap:12px;margin-bottom:6px;flex-wrap:wrap}
.sechead .t{font-weight:600}
.secbtns{display:flex;gap:6px}
#secCv{display:block;max-width:100%;cursor:crosshair}
.stage.has-section #readout{top:14px;bottom:auto}
.stage.has-section #hint{display:none}
#drawTip{left:50%;top:14px;transform:translateX(-50%);padding:8px 12px;font-size:13px;max-width:min(520px,calc(100% - 180px))}
.stage.drawing #gl{cursor:crosshair}
.stage.drawing.has-section #readout{top:auto;bottom:14px}
.gl{position:absolute;font-size:11px;color:var(--muted);pointer-events:none;white-space:nowrap;transform:translate(-50%,4px)}
.gl.n{transform:translate(-100%,-50%);padding-right:6px}
#swipe{position:absolute;top:0;bottom:0;left:50%;width:0;z-index:1}
#swipe .bar{position:absolute;top:0;bottom:0;left:-1px;width:2px;background:var(--accent);pointer-events:none}
#swipe .knob{position:absolute;top:50%;left:0;transform:translate(-50%,-50%);width:32px;height:32px;border-radius:50%;border:0;background:var(--accent);color:var(--accent-ink);cursor:ew-resize;font:600 15px Barlow,system-ui,sans-serif;touch-action:none}
#swipe .lab{position:absolute;top:calc(50% + 24px);font-size:12px;background:var(--card);border:1px solid var(--rule);border-radius:4px;padding:1px 6px;white-space:nowrap;pointer-events:none}
#swipe .lab.l{right:8px} #swipe .lab.r{left:8px}
.xl{position:absolute;transform:translate(-50%,-130%);font-weight:600;font-size:13px;color:var(--accent-ink);background:var(--accent);padding:1px 6px;border-radius:4px;pointer-events:none}
textarea{width:100%;font:inherit;font-size:12.5px;background:var(--field);color:var(--ink);border:1px solid var(--rule);border-radius:5px;padding:6px;margin:6px 0;resize:vertical}
.btn:disabled{opacity:.45;cursor:default}
@media (max-width:1100px){ #hint{display:none} }
@media (max-width:780px){
  body{height:auto}
  .app{grid-template-columns:1fr;grid-template-rows:62vh auto;height:auto}
  .stage{height:62vh;order:1}
  .rail{order:2;border-right:0;border-top:1px solid var(--rule)}
  #logwrap{top:80px;max-height:calc(100% - 190px)}
}

/* faults */
.fl{position:absolute;transform:translate(-50%,-140%);font-weight:600;font-size:12px;color:#fff;background:var(--fault);padding:1px 6px;border-radius:4px;pointer-events:none}
.fl.sel{box-shadow:0 0 0 2px var(--ink)} .fl.off{opacity:.5}
ol.flist{list-style:none;margin:8px 0 0;padding:0;display:grid;gap:4px}
.fitem{width:100%;text-align:left;font:inherit;font-size:12.5px;border:1px solid var(--rule);background:var(--field);color:var(--ink);border-radius:5px;padding:6px 8px;cursor:pointer;display:flex;gap:8px;align-items:baseline}
.fitem .fn{font-weight:600;color:var(--fault);flex:none}
.fitem.sel{border-color:var(--fault);box-shadow:inset 3px 0 0 var(--fault)}
.fitem.off{opacity:.6}
#faultEd{margin-top:10px;border:1px solid var(--rule);border-radius:6px;padding:10px;background:var(--field)}
#faultEd .fname{flex:1;font-weight:600;color:var(--fault)}
.btn:disabled{opacity:.45;cursor:default}
#fNameIn{flex:1;min-width:0;font:inherit;font-weight:600;color:var(--fault);background:var(--field);border:1px solid var(--rule);border-radius:5px;padding:4px 7px}
#fNameIn:focus-visible{outline:2px solid var(--accent);outline-offset:1px}