:root{
  --bg:#e6eaef; --panel:#f6f8fa; --ink:#172033; --muted:#5d6b80; --line:#cdd5df;
  --accent:#2456c4; --accent-ink:#fff; --danger:#c2362b; --field:#fff;
  --font:"Segoe UI","Inter",system-ui,-apple-system,"Helvetica Neue",Arial,sans-serif;
}
@media (prefers-color-scheme:dark){
  :root{--bg:#10151d; --panel:#1a212c; --ink:#e7ecf3; --muted:#93a1b5; --line:#2e3948;
        --accent:#6f9bff; --accent-ink:#0c1424; --danger:#ff8a80; --field:#121923}
}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:14px/1.45 var(--font);display:flex;flex-direction:column}
button,input,select{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.top{display:flex;justify-content:space-between;align-items:center;padding:10px 18px;background:var(--panel);border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:baseline;gap:12px}
.brand b{font-size:17px;letter-spacing:.01em}
.brand span{color:var(--muted)}
#auth{display:flex;gap:10px;align-items:center}
.layout{flex:1;display:grid;grid-template-columns:360px 1fr;min-height:0}
.panel{background:var(--panel);border-right:1px solid var(--line);padding:14px 16px;overflow:auto}
.stage{display:flex;flex-direction:column;min-width:0;min-height:0;padding:12px 16px}
.tabs{display:flex;gap:4px;margin-bottom:14px;border-bottom:1px solid var(--line)}
.tabs button{border:0;background:none;padding:8px 12px;cursor:pointer;color:var(--muted);border-bottom:2px solid transparent;margin-bottom:-1px}
.tabs button.on{color:var(--ink);border-color:var(--accent);font-weight:600}
.field{display:flex;flex-direction:column;gap:4px;margin:0 0 10px;color:var(--muted);font-size:13px}
.field input,.field select,select{background:var(--field);border:1px solid var(--line);border-radius:6px;padding:7px 9px;color:var(--ink);min-width:0;width:100%}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:10px;align-items:end}
.check{display:flex;gap:8px;align-items:center;margin:0 0 12px;line-height:1.25}
table.coords{width:100%;border-collapse:collapse;margin:4px 0 14px;font-variant-numeric:tabular-nums}
.coords th{font-weight:600;color:var(--muted);text-align:center;padding:2px}
.coords td{padding:3px}
.coords td:first-child{font-weight:700;font-style:italic;width:28px;text-align:center}
.coords input{width:100%;padding:6px 4px;text-align:center;background:var(--field);border:1px solid var(--line);border-radius:5px;-moz-appearance:textfield}
.coords input::-webkit-outer-spin-button,.coords input::-webkit-inner-spin-button{-webkit-appearance:none}
.coords input.bad{border-color:var(--danger)}
details{border-top:1px solid var(--line);padding:10px 0;margin-bottom:6px}
summary{cursor:pointer;font-weight:600;margin-bottom:10px}
.save{border-top:1px solid var(--line);padding-top:12px}
.btns{display:flex;gap:8px;flex-wrap:wrap}
button{border:1px solid var(--line);background:var(--field);border-radius:6px;padding:7px 12px;cursor:pointer}
button:hover{border-color:var(--accent)}
button.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent);font-weight:600}
.muted{color:var(--muted);font-size:13px;margin:8px 0 0}
.toolbar{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:8px}
.zoom,.export{display:flex;gap:6px;align-items:center}
.export .muted{margin:0 4px 0 0}
.info{min-height:20px;font-size:13px;color:var(--muted);margin-bottom:8px;font-variant-numeric:tabular-nums}
.info .warn{color:var(--danger)}
.viewport{flex:1;min-height:0;overflow:auto;border:1px solid var(--line);border-radius:6px;background:var(--bg);padding:14px}
.sheet{width:100%;background:#fff;box-shadow:0 1px 3px rgba(0,0,0,.25),0 8px 24px rgba(0,0,0,.12);line-height:0}
.sheet svg{display:block;width:100%;height:auto}
.sheet.loading{opacity:.55}
.saved{list-style:none;margin:0;padding:0}
.saved li{display:flex;justify-content:space-between;gap:8px;align-items:center;padding:9px 0;border-bottom:1px solid var(--line)}
.saved .t{display:flex;flex-direction:column;min-width:0}
.saved .t b{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.saved small{color:var(--muted)}
.saved li.on b{color:var(--accent)}
.empty{color:var(--muted);padding:12px 0}
dialog{border:1px solid var(--line);border-radius:10px;background:var(--panel);color:var(--ink);width:min(360px,92vw);padding:20px}
dialog::backdrop{background:rgba(10,15,25,.5)}
dialog h2{margin:0 0 14px;font-size:18px}
.err{color:var(--danger);min-height:20px;margin:0 0 6px}
.toast{position:fixed;left:50%;bottom:22px;transform:translate(-50%,20px);background:var(--ink);color:var(--bg);padding:9px 16px;border-radius:8px;opacity:0;pointer-events:none;transition:opacity .2s,transform .2s}
.toast.show{opacity:1;transform:translate(-50%,0)}
@media (max-width:860px){
  .layout{grid-template-columns:1fr;display:block}
  .panel{border-right:0;border-bottom:1px solid var(--line)}
  .viewport{height:70vh}
  .brand span{display:none}
}
@media (prefers-reduced-motion:reduce){.toast{transition:none}}

.home{padding:32px 24px;max-width:1000px;margin:0 auto;width:100%}
.home h1{font-size:22px;margin:0 0 18px}
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:14px}
.card{display:flex;flex-direction:column;gap:6px;padding:16px;border:1px solid var(--line);border-radius:8px;background:var(--panel);color:inherit;text-decoration:none}
.card b{font-size:16px}.card small{color:var(--muted)}
a.card:hover{border-color:var(--accent)}
.card.off{opacity:.55}
a.brand{color:inherit;text-decoration:none}
[hidden]{display:none!important}