:root{
  --bg:#f5f6f8; --panel:#ffffff; --ink:#0f172a; --ink2:#334155; --mute:#64748b; --line:#e2e6ee; --line2:#cbd2de;
  --brand:#1d4ed8; --brand2:#1e40af; --brand-soft:#e8efff; --accent:#0ea5a4; --warn:#b45309; --warn-soft:#fff4e0; --bad:#b91c1c; --bad-soft:#fde8e8; --good:#15803d; --good-soft:#e6f6ea;
  --radius:10px; --shadow:0 1px 2px rgba(15,23,42,.06),0 8px 24px -12px rgba(15,23,42,.18);
  font-family:Inter,system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
}
*{box-sizing:border-box}
html,body{margin:0;background:var(--bg);color:var(--ink);font-size:14px;line-height:1.45}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3{margin:0 0 .5em;letter-spacing:-.01em}
h2{font-size:13px;text-transform:uppercase;letter-spacing:.08em;color:var(--mute);font-weight:700}
h3{font-size:18px}
code{background:#eef1f6;padding:1px 5px;border-radius:4px;font-size:12px}
.hidden{display:none!important}
.muted{color:var(--mute)}

/* top bar */
.topbar{display:flex;align-items:center;justify-content:space-between;padding:10px 20px;background:var(--panel);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;font-size:17px;color:var(--ink);letter-spacing:-.02em}
.brand .mark{width:20px;height:20px;border-radius:5px;background:linear-gradient(135deg,var(--brand),var(--accent));box-shadow:inset 0 0 0 2px #fff,inset 0 0 0 4px var(--brand2)}
.topbar nav{display:flex;align-items:center;gap:18px}
.topbar nav a{color:var(--ink2);font-weight:500}

/* layout */
.workspace{display:grid;grid-template-columns:520px 1fr;gap:16px;padding:16px 20px;min-height:calc(100vh - 100px);align-items:start}
@media (max-width:1100px){.workspace{grid-template-columns:1fr}}
.panel{min-width:0}
.inputs{position:sticky;top:64px;max-height:calc(100vh - 80px);overflow:auto;padding-right:2px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:14px 16px;margin-bottom:12px;box-shadow:var(--shadow)}
.card-head{display:flex;justify-content:space-between;align-items:center}
.card-head h2{margin:0}
.units select{font-size:12px;padding:3px 6px}

label{display:flex;flex-direction:column;gap:4px;font-size:12px;color:var(--ink2);font-weight:500}
label.inline{flex-direction:row;align-items:center;gap:8px}
label.check{flex-direction:row;align-items:center;gap:8px;font-weight:400;color:var(--ink);margin-top:8px}
input,select,textarea{font:inherit;font-size:13px;color:var(--ink);background:#fff;border:1px solid var(--line2);border-radius:7px;padding:7px 9px;min-width:0}
input:focus,select:focus,textarea:focus{outline:2px solid var(--brand-soft);border-color:var(--brand)}
input[type=number]{width:100%}
.row{display:flex;align-items:center;gap:12px;margin:8px 0}
.row.wrap{flex-wrap:wrap}
.row.right{justify-content:flex-end}
.gap{gap:8px}
.grid4{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}
.hint{font-size:12px;color:var(--mute);margin:8px 0 0}
.error{color:var(--bad);background:var(--bad-soft);padding:8px 10px;border-radius:7px;font-size:13px}

.btn{font:inherit;font-weight:600;font-size:13px;border:1px solid var(--line2);background:#fff;color:var(--ink);border-radius:8px;padding:8px 12px;cursor:pointer;display:inline-flex;align-items:center;gap:6px;transition:background .12s,border-color .12s}
.btn:hover{background:#f3f5f9}
.btn.primary{background:var(--brand);color:#fff;border-color:var(--brand)}
.btn.primary:hover{background:var(--brand2)}
.btn.ghost{background:transparent}
.btn.danger{color:var(--bad)}
.btn.small{padding:6px 10px;font-size:12px}
.btn.tiny{padding:4px 8px;font-size:11px;border-radius:6px}
.btn.big{padding:12px 18px;font-size:15px;width:100%;justify-content:center}
.btn:disabled{opacity:.55;cursor:not-allowed}
.badge{font-size:10px;font-weight:800;letter-spacing:.06em;padding:2px 6px;border-radius:5px;background:var(--brand-soft);color:var(--brand2)}
.badge.pro{background:linear-gradient(135deg,#f59e0b,#f97316);color:#fff}
.badge.pro-mini{background:#fff4e0;color:#b45309;margin-left:4px}

/* items table */
.table-wrap{overflow-x:auto;margin:6px -6px 0}
table.items{border-collapse:collapse;width:100%;min-width:720px}
table.items th{font-size:11px;text-transform:uppercase;letter-spacing:.05em;color:var(--mute);text-align:left;padding:4px 6px;font-weight:600;white-space:nowrap}
table.items td{padding:3px 4px;vertical-align:middle}
table.items input,table.items select{padding:5px 6px;font-size:12px;width:100%}
table.items td.num input{width:58px;text-align:right}
table.items td.qty input{width:50px;text-align:right}
table.items td.name input{min-width:110px}
table.items input.maxload{width:64px;margin-left:4px}
input.ro{background:#f3f5f9;color:var(--ink2)}
table.items td.sel select{width:auto}
table.items td.chk{text-align:center}
table.items td.chk input{width:16px;height:16px;padding:0}
table.items td.color input{width:26px;height:26px;padding:0;border:none;background:none;cursor:pointer}
table.items td.del button{border:none;background:none;color:var(--mute);cursor:pointer;font-size:14px;padding:2px 6px}
table.items td.del button:hover{color:var(--bad)}
table.items tr.invalid td.num input{border-color:var(--bad)}

.actions{position:sticky;bottom:0;padding:10px 0 6px;background:linear-gradient(180deg,rgba(245,246,248,0),var(--bg) 35%)}
.progress{margin-top:8px;height:24px;position:relative;background:#e8ecf3;border-radius:7px;overflow:hidden}
.progress .bar{position:absolute;inset:0;width:0;background:linear-gradient(90deg,var(--brand),var(--accent));transition:width .2s}
.progress span{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:600;color:var(--ink)}

/* results */
.results{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px;display:flex;flex-direction:column;min-height:640px}
.empty{flex:1;display:flex;align-items:center;justify-content:center}
.empty-inner{max-width:560px;text-align:center}
.empty h1{font-size:26px;line-height:1.2;margin-bottom:14px}
.summary{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:10px;margin-bottom:12px}
.tile{background:#f7f8fb;border:1px solid var(--line);border-radius:9px;padding:10px 12px}
.tile .k{font-size:11px;text-transform:uppercase;letter-spacing:.06em;color:var(--mute);font-weight:600}
.tile .v{font-size:22px;font-weight:800;letter-spacing:-.02em;margin-top:2px}
.tile .s{font-size:11px;color:var(--mute)}
.tile.warn{background:var(--warn-soft);border-color:#f3d9a8}
.tile.warn .v{color:var(--warn)}
.tabs{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:10px}
.tab{border:1px solid var(--line2);background:#fff;border-radius:999px;padding:5px 12px;font-size:12px;font-weight:600;cursor:pointer}
.tab.active{background:var(--ink);color:#fff;border-color:var(--ink)}
.viewer-wrap{display:grid;grid-template-columns:1fr 260px;gap:12px;flex:1;min-height:420px}
@media (max-width:1400px){.viewer-wrap{grid-template-columns:1fr}}
.viewer{position:relative;background:linear-gradient(180deg,#f8fafc,#e9edf3);border:1px solid var(--line);border-radius:9px;overflow:hidden;min-height:420px}
.viewer canvas{display:block;width:100%;height:100%}
.viewer-tools{position:absolute;top:10px;left:10px;display:flex;gap:6px;align-items:center;background:rgba(255,255,255,.85);backdrop-filter:blur(4px);padding:6px;border-radius:8px;border:1px solid var(--line)}
.viewer-tools label.tiny{margin:0 0 0 6px;font-size:11px}
.seq{position:absolute;bottom:10px;left:10px;right:10px;display:flex;gap:10px;align-items:center;background:rgba(255,255,255,.88);backdrop-filter:blur(4px);padding:8px 10px;border-radius:8px;border:1px solid var(--line)}
.seq input[type=range]{flex:1;padding:0;border:none}
.seq span{font-size:12px;font-weight:600;min-width:110px;text-align:right}
.tooltip{position:absolute;pointer-events:none;background:var(--ink);color:#fff;font-size:12px;padding:6px 9px;border-radius:6px;transform:translate(12px,12px);white-space:nowrap;z-index:5}
.side{display:flex;flex-direction:column;gap:12px}
.stats{background:#f7f8fb;border:1px solid var(--line);border-radius:9px;padding:12px}
.stat{margin-bottom:10px}
.stat .k{font-size:11px;text-transform:uppercase;letter-spacing:.06em;color:var(--mute);font-weight:600;display:flex;justify-content:space-between}
.stat .k b{color:var(--ink);font-size:12px}
.meter{height:8px;background:#e3e7ee;border-radius:999px;overflow:hidden;margin-top:4px}
.meter i{display:block;height:100%;background:var(--brand);border-radius:999px}
.meter i.warn{background:#f59e0b}
.meter i.bad{background:var(--bad)}
.cog{font-size:12px;color:var(--ink2);margin-top:6px}
.legend{background:#f7f8fb;border:1px solid var(--line);border-radius:9px;padding:10px 12px;font-size:12px;max-height:260px;overflow:auto}
.legend .li{display:flex;align-items:center;gap:8px;padding:3px 0;border-bottom:1px dashed var(--line)}
.legend .li:last-child{border-bottom:none}
.legend .sw{width:12px;height:12px;border-radius:3px;border:1px solid rgba(0,0,0,.15);flex:0 0 12px}
.legend .n{flex:1}
.legend .c{font-variant-numeric:tabular-nums;color:var(--ink2)}
.unplaced{margin-top:12px;background:var(--warn-soft);border:1px solid #f3d9a8;border-radius:9px;padding:10px 12px;font-size:13px}
.exports{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px;padding-top:12px;border-top:1px solid var(--line)}

/* modal */
.modal{position:fixed;inset:0;background:rgba(15,23,42,.45);display:flex;align-items:center;justify-content:center;z-index:50;padding:20px}
.modal-box{background:#fff;border-radius:12px;padding:20px 22px;max-width:640px;width:100%;box-shadow:0 30px 80px -20px rgba(0,0,0,.4)}
.modal textarea{width:100%;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:12px}
.ticks{padding-left:18px;margin:8px 0 12px}
.ticks li{margin:4px 0}

.foot{padding:14px 20px;color:var(--mute);font-size:12px;border-top:1px solid var(--line);background:var(--panel)}