/* ============================================================
   Pneumatic System Simulator — styles
   Light engineering theme, zero dependencies
   ============================================================ */
:root{
  --bg:#f2f5f9;
  --panel:#ffffff;
  --border:#d8e0ea;
  --border-strong:#b9c6d8;
  --text:#1c2733;
  --text-soft:#5b6b7f;
  --text-faint:#8a99ab;
  --accent:#1e5aa8;
  --accent-hi:#2f74c9;
  --accent-soft:#e8f0fb;
  --ok:#1a9e6c;
  --warn:#c98a1b;
  --err:#c4453c;
  --mono:"Consolas","SF Mono","Menlo","Courier New",monospace;
  --shadow:0 1px 3px rgba(20,40,70,.08),0 4px 14px rgba(20,40,70,.06);
  --radius:6px;
  --topbar-h:52px;
  --status-h:26px;
}
*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%}
body{
  font-family:-apple-system,"Segoe UI",Roboto,"Helvetica Neue","PingFang SC","Hiragino Sans GB","Microsoft YaHei",Arial,sans-serif;
  font-size:13.5px;color:var(--text);background:var(--bg);
  -webkit-font-smoothing:antialiased;overflow:hidden;
}
#app{display:flex;flex-direction:column;height:100vh}
.mono{font-family:var(--mono)}
.hidden{display:none!important}

/* ============ TOP BAR ============ */
.topbar{
  height:var(--topbar-h);flex:0 0 var(--topbar-h);
  display:flex;align-items:center;gap:6px;padding:0 10px;
  background:linear-gradient(180deg,#ffffff,#f7fafd);
  border-bottom:1px solid var(--border-strong);
  box-shadow:var(--shadow);z-index:10;
}
.brand{display:flex;align-items:center;gap:9px;padding-right:4px;user-select:none}
.logo{width:30px;height:30px;flex:0 0 auto}
.logo rect{fill:var(--accent-soft);stroke:var(--accent);stroke-width:1.3}
.logo line,.logo circle{stroke:var(--accent);stroke-width:1.3;fill:none}
.logo circle{fill:#fff}
.brand-text{display:flex;flex-direction:column;line-height:1.15}
.brand-title{font-weight:700;font-size:14.5px;color:var(--accent);white-space:nowrap}
.brand-sub{font-size:10.5px;color:var(--text-soft);letter-spacing:.4px;white-space:nowrap}
.tb-sep{width:1px;height:24px;background:var(--border);margin:0 3px;flex:0 0 auto}
.spacer{flex:1 1 auto}
.tb-group{display:flex;align-items:center;gap:4px;flex:0 0 auto}

.tb{
  display:inline-flex;align-items:center;gap:5px;height:32px;padding:0 10px;
  border:1px solid var(--border-strong);border-radius:var(--radius);
  background:#fff;color:var(--text);font-size:13px;cursor:pointer;
  transition:background .12s,border-color .12s,box-shadow .12s;white-space:nowrap;
}
.tb:hover{background:var(--accent-soft);border-color:var(--accent-hi)}
.tb:active{transform:translateY(1px)}
.tb .ico{font-size:13px;line-height:1}
.tb.primary{background:var(--accent);border-color:var(--accent);color:#fff;font-weight:600}
.tb.primary:hover{background:var(--accent-hi)}
.tb.small{height:26px;padding:0 8px;font-size:12px}
.tb.site{text-decoration:none}
.tb.site .lbl{font-size:12.5px;font-weight:600;color:var(--accent)}
.tb.site:hover .lbl{color:var(--accent-hi)}

.slider-inline{display:flex;align-items:center;gap:6px;height:32px;padding:0 8px;border:1px solid var(--border-strong);border-radius:var(--radius);background:#fff}
.slider-inline .ico{font-size:13px}
.slider-inline input[type=range]{width:74px;accent-color:var(--accent)}
.slider-inline .mono{font-size:11px;color:var(--text-soft);min-width:34px;text-align:right}

.lang-sel{
  height:32px;padding:0 8px;border:1px solid var(--border-strong);border-radius:var(--radius);
  background:#fff;color:var(--text);font-size:13px;cursor:pointer;outline:none;
}
.lang-sel:focus{border-color:var(--accent)}

/* ============ WORKSPACE ============ */
.workspace{
  flex:1 1 auto;display:flex;gap:0;min-height:0;position:relative;
}

/* ---- panels ---- */
.panel{
  background:var(--panel);display:flex;flex-direction:column;min-height:0;
}
.panel.left{width:236px;flex:0 0 236px;border-right:1px solid var(--border-strong)}
.panel.right{width:332px;flex:0 0 332px;border-left:1px solid var(--border-strong)}

.panel-tabs{display:flex;border-bottom:1px solid var(--border);flex:0 0 auto;background:#fbfcfe}
.ptab{
  flex:1 1 0;height:36px;border:none;background:transparent;cursor:pointer;
  font-size:12.5px;font-weight:600;color:var(--text-soft);
  border-bottom:2px solid transparent;
}
.ptab:hover{color:var(--accent)}
.ptab.active{color:var(--accent);border-bottom-color:var(--accent);background:#fff}

.ptab-body{flex:1 1 auto;min-height:0;display:flex;flex-direction:column;overflow:hidden}

/* ---- palette ---- */
.panel-search{padding:8px 10px;flex:0 0 auto}
.panel-search input{
  width:100%;height:30px;padding:0 10px;border:1px solid var(--border-strong);
  border-radius:var(--radius);font-size:13px;outline:none;
}
.panel-search input:focus{border-color:var(--accent);box-shadow:0 0 0 2px rgba(30,90,168,.12)}
.palette-list{flex:1 1 auto;overflow-y:auto;padding:4px 8px 10px}
.palette-item{
  display:flex;align-items:center;gap:9px;padding:7px 9px;margin:3px 0;
  border:1px solid var(--border);border-radius:var(--radius);background:#fff;
  cursor:grab;user-select:none;transition:border-color .12s,box-shadow .12s,transform .12s;
}
.palette-item:hover{border-color:var(--accent-hi);box-shadow:var(--shadow);transform:translateY(-1px)}
.palette-item:active{cursor:grabbing}
.palette-item .pico{width:52px;height:30px;flex:0 0 auto}
.palette-item .pico svg{width:100%;height:100%}
.palette-item .pname{font-size:12.5px;font-weight:600;line-height:1.2}
.palette-item .psub{font-size:10.5px;color:var(--text-faint);line-height:1.2}
.hint{font-size:11px;color:var(--text-faint);padding:4px 10px 8px;flex:0 0 auto}

/* ---- learn ---- */
.learn-list{flex:1 1 auto;overflow-y:auto;padding:8px}
.learn-item{
  padding:9px 11px;margin:4px 0;border:1px solid var(--border);border-radius:var(--radius);
  background:#fff;cursor:pointer;transition:border-color .12s,box-shadow .12s;
}
.learn-item:hover{border-color:var(--accent-hi);box-shadow:var(--shadow)}
.learn-item.active{border-color:var(--accent);background:var(--accent-soft)}
.learn-item .li-title{font-size:13px;font-weight:700}
.learn-item .li-sub{font-size:11px;color:var(--text-soft);margin-top:2px}

/* ---- tools ---- */
.tools-list{flex:1 1 auto;overflow-y:auto;padding:8px}
.tool-item{
  display:flex;flex-direction:column;align-items:flex-start;gap:2px;width:100%;
  padding:9px 11px;margin:4px 0;border:1px solid var(--border);border-radius:var(--radius);
  background:#fff;cursor:pointer;text-align:left;transition:border-color .12s,box-shadow .12s;
}
.tool-item:hover{border-color:var(--accent-hi);box-shadow:var(--shadow)}
.tool-item .ico{font-size:16px}
.tool-item .ti{font-size:13px;font-weight:700}
.tool-item .td{font-size:11px;color:var(--text-soft)}

/* ============ CANVAS ============ */
.canvas-wrap{
  flex:1 1 auto;display:flex;flex-direction:column;min-width:0;min-height:0;background:var(--bg);
}
.canvas-toolbar{
  flex:0 0 36px;display:flex;align-items:center;gap:4px;padding:0 8px;
  border-bottom:1px solid var(--border);background:#fff;
}
.ct-title{font-size:12.5px;font-weight:700;color:var(--text-soft)}
.ct-spacer{flex:1 1 auto}
.canvas-holder{
  flex:1 1 auto;position:relative;min-height:0;overflow:hidden;
  background:
    radial-gradient(circle at 1px 1px, #dbe3ee 1px, transparent 0) 0 0/22px 22px,
    var(--bg);
}
#canvas{position:absolute;left:0;top:0;width:100%;height:100%;touch-action:none}
.canvas-empty{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);
  display:flex;flex-direction:column;align-items:center;gap:8px;
  color:var(--text-faint);font-size:13px;text-align:center;pointer-events:none;
}
.canvas-empty .ce-ico{font-size:34px;opacity:.6}

/* svg elements */
.comp-group{cursor:grab}
.comp-group.selected .comp-frame{stroke:var(--accent);stroke-width:2;opacity:1}
.comp-frame{stroke:transparent;stroke-width:2;opacity:0}
.comp-shape{stroke:#22344d;stroke-width:1.4;fill:#fff}
.comp-shape .port{stroke:var(--accent);stroke-width:1.4;fill:#fff}
.port-ring{stroke:var(--accent-hi);stroke-width:1.6;fill:rgba(47,116,201,.14)}
.wire-line{stroke:#4a6fa5;stroke-width:1.8;fill:none;stroke-linejoin:round}
.wire-line.wire-sig{stroke:#1d9e75;stroke-width:1.6;stroke-dasharray:6 4}
.wire-line.selected{stroke:var(--accent);stroke-width:2.4}
.wire-ghost{stroke:var(--accent);stroke-width:1.8;stroke-dasharray:5 4;fill:none}
.press-text{font-size:9px;font-family:var(--mono);fill:var(--accent)}
.comp-label{font-size:10.5px;fill:var(--text-soft)}
.flow-arrow{fill:#1e88e5;opacity:.85}

/* ============ LEARN CARD ============ */
.learn-card{
  position:absolute;right:14px;top:14px;width:300px;max-height:calc(100% - 40px);
  background:#fff;border:1px solid var(--border-strong);border-radius:10px;
  box-shadow:var(--shadow);display:flex;flex-direction:column;z-index:5;overflow:hidden;
}
.lc-head{
  display:flex;align-items:center;justify-content:space-between;padding:8px 10px;
  background:var(--accent);color:#fff;flex:0 0 auto;
}
.lc-title{font-size:13px;font-weight:700}
.lc-head .tb{background:rgba(255,255,255,.15);border-color:transparent;color:#fff;height:24px;padding:0 7px}
.lc-steps{flex:1 1 auto;overflow-y:auto;padding:10px 12px;font-size:12.5px;line-height:1.55}
.lc-step{display:none}
.lc-step.active{display:block}
.lc-step .lc-step-title{font-weight:700;color:var(--accent);margin-bottom:4px}
.lc-nav{display:flex;align-items:center;gap:8px;padding:6px 10px;border-top:1px solid var(--border);flex:0 0 auto}
.lc-nav .tb{flex:1 1 0;justify-content:center}
.lc-count{font-size:12px;color:var(--text-soft);min-width:40px;text-align:center}
.lc-actions{display:flex;gap:6px;padding:0 10px 10px;flex:0 0 auto;flex-wrap:wrap}
.lc-actions .tb{flex:1 1 0;justify-content:center}

/* ============ RIGHT PANEL ============ */
.plot-box{margin:8px 10px 0;border:1px solid var(--border);border-radius:var(--radius);padding:6px 8px 2px;background:#fbfcfe}
.plot-title{font-size:11px;font-weight:700;color:var(--text-soft);margin-bottom:4px}
.plot-box canvas{width:100%;height:auto;display:block;background:#fff;border:1px solid var(--border);border-radius:4px}
.plot-legend{display:flex;flex-wrap:wrap;gap:10px;padding:8px 12px;font-size:11px;color:var(--text-soft)}
.pl-item{display:flex;align-items:center;gap:5px}
.pl-swatch{width:10px;height:10px;border-radius:2px;display:inline-block}

/* ---- scope ---- */
.scope-head{display:flex;align-items:center;gap:8px;margin:10px 10px 0;padding:6px 8px;border:1px solid var(--border);border-radius:var(--radius) var(--radius) 0 0;background:#eef2f8}
.scope-title{font-size:11px;font-weight:700;color:var(--text-soft)}
.scope-ch{display:flex;gap:4px;flex:1;flex-wrap:wrap}
.scope-ch .ch{border:1px solid var(--border);background:#fff;color:var(--text-soft);border-radius:4px;padding:2px 7px;font:11px Consolas,monospace;cursor:pointer}
.scope-ch .ch.active{background:var(--accent);color:#fff;border-color:var(--accent)}
#plotScope{width:calc(100% - 20px);margin:0 10px;display:block;background:#fbfcfe;border:1px solid var(--border);border-radius:0 0 var(--radius) var(--radius)}
.scope-read{font-size:11px;color:var(--text-soft);padding:4px 12px 8px;min-height:14px}

/* ---- PWA update banner ---- */
.update-banner{position:fixed;left:12px;bottom:12px;z-index:300;display:none;align-items:center;gap:12px;background:#1e5aa8;color:#fff;padding:10px 14px;border-radius:10px;box-shadow:0 4px 16px rgba(0,0,0,.25);font-size:13px;max-width:420px}
.update-banner.show{display:flex}
.update-banner .ub-msg{flex:1}
.update-banner .tb{background:#fff;color:#1e5aa8;border:none}

/* ---- templates ---- */
.tpl-list{display:flex;flex-direction:column;gap:6px;max-height:320px;overflow:auto;margin-bottom:12px}
.tpl-item{display:flex;flex-direction:column;gap:2px;text-align:left;border:1px solid var(--border);background:#fff;border-radius:8px;padding:8px 12px;cursor:pointer}
.tpl-item:hover{border-color:var(--accent);background:#f4f8fe}
.tpl-name{font-size:13px;font-weight:700;color:var(--accent)}
.tpl-desc{font-size:12px;color:var(--text-soft)}

/* ---- quiz ---- */
.quiz-q{font-size:13.5px;font-weight:700;color:var(--text);margin:10px 0 8px}
.quiz-opt{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--text-soft);padding:6px 8px;border:1px solid var(--border);border-radius:6px;margin-bottom:6px;cursor:pointer}
.quiz-opt:hover{border-color:var(--accent);background:#f4f8fe}
.quiz-result{font-size:16px;font-weight:700;color:var(--accent);margin:12px 0 4px}
.quiz-result-sub{font-size:12.5px;color:var(--text-soft)}

/* ---- params ---- */
.params-empty{padding:16px;font-size:12.5px;color:var(--text-faint);text-align:center}
.params-form{flex:1 1 auto;overflow-y:auto;padding:10px}
.pf-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:8px}
.pf-name{font-size:14px;font-weight:700;color:var(--accent)}
.pf-type{font-size:11px;color:var(--text-faint)}
.pf-grid{display:grid;grid-template-columns:1fr;gap:7px}
.pf-row{display:flex;flex-direction:column;gap:3px}
.pf-row label{font-size:11.5px;font-weight:600;color:var(--text-soft)}
.pf-row input,.pf-row select{
  height:28px;padding:0 8px;border:1px solid var(--border-strong);border-radius:4px;
  font-size:12.5px;outline:none;background:#fff;color:var(--text);width:100%;
}
.pf-row input:focus,.pf-row select:focus{border-color:var(--accent)}
.pf-row .pf-unit{font-size:10.5px;color:var(--text-faint);margin-left:4px}
.pf-hint{margin-top:8px;font-size:11px;color:var(--text-soft);background:var(--accent-soft);border-radius:4px;padding:6px 8px;line-height:1.5}
.pf-btn{margin-top:8px;width:100%}

/* ---- calc ---- */
.calc-units-row{
  display:flex;align-items:center;gap:8px;padding:8px 12px;border-bottom:1px solid var(--border);
  font-size:12px;color:var(--text-soft);flex:0 0 auto;flex-wrap:wrap;
}
.calc-units-row select{
  height:26px;padding:0 6px;border:1px solid var(--border-strong);border-radius:4px;
  font-size:12px;outline:none;background:#fff;flex:1 1 auto;min-width:120px;
}
.calc-body{flex:1 1 auto;overflow-y:auto;padding:10px 12px}
.calc-card{border:1px solid var(--border);border-radius:8px;padding:10px 12px;margin-bottom:10px;background:#fff}
.calc-card h3{font-size:13.5px;font-weight:700;margin-bottom:2px}
.calc-card .cc-sub{font-size:11px;color:var(--text-soft);margin-bottom:8px}
.cc-formula{
  font-family:var(--mono);font-size:11.5px;background:var(--accent-soft);color:var(--accent);
  padding:5px 8px;border-radius:4px;margin-bottom:8px;line-height:1.5;
}
.calc-grid{display:grid;grid-template-columns:1fr 1fr;gap:7px}
.cc-field{display:flex;flex-direction:column;gap:2px}
.cc-field label{font-size:11px;font-weight:600;color:var(--text-soft)}
.cc-field input{
  height:28px;padding:0 8px;border:1px solid var(--border-strong);border-radius:4px;
  font-size:12.5px;outline:none;width:100%;background:#fff;
}
.cc-field input:focus{border-color:var(--accent)}
.cc-field .cc-unit{font-size:10px;color:var(--text-faint)}
.cc-result{
  margin-top:8px;padding:8px 10px;border-radius:6px;background:var(--accent-soft);
  border:1px solid rgba(30,90,168,.25);font-size:12.5px;line-height:1.6;
}
.cc-result .cr-big{font-size:17px;font-weight:800;color:var(--accent)}
.cc-result .cr-note{font-size:11px;color:var(--text-soft);margin-top:3px}
.cc-result.warn{background:#fdf3e3;border-color:rgba(201,138,27,.35)}
.cc-result.warn .cr-big{color:var(--warn)}

/* ============ STATUS BAR ============ */
.statusbar{
  height:var(--status-h);flex:0 0 var(--status-h);
  display:flex;align-items:center;gap:10px;padding:0 12px;
  background:#fff;border-top:1px solid var(--border);
  font-size:11.5px;color:var(--text-soft);
}
.statusbar .sb-spacer{flex:1 1 auto}
.statusbar .sb-sep{width:1px;height:14px;background:var(--border)}
#statusSim{color:var(--text-soft)}
#statusSim.running{color:var(--ok)}

/* toast */
.toast{
  position:fixed;left:50%;bottom:44px;transform:translateX(-50%);
  background:#22344d;color:#fff;padding:9px 18px;border-radius:8px;font-size:13px;
  box-shadow:var(--shadow);z-index:99;opacity:0;pointer-events:none;
  transition:opacity .25s;max-width:80vw;text-align:center;
}
.toast.show{opacity:1}

/* modal */
.modal-mask{
  position:fixed;inset:0;background:rgba(20,35,55,.35);z-index:80;
  display:flex;align-items:center;justify-content:center;
}
.modal{
  background:#fff;border-radius:12px;border:1px solid var(--border-strong);
  box-shadow:var(--shadow);padding:18px 20px;width:min(440px,92vw);
}
.modal-title{font-size:15px;font-weight:700;color:var(--accent);margin-bottom:8px}
.modal-hint{font-size:12.5px;color:var(--text-soft);line-height:1.6;margin-bottom:12px}
.modal-row{display:flex;gap:8px;margin-bottom:14px}
.modal-row select{
  flex:1 1 0;height:34px;padding:0 8px;border:1px solid var(--border-strong);
  border-radius:6px;font-size:13px;background:#fff;outline:none;
}
.modal-actions{display:flex;gap:8px;justify-content:flex-end}
.modal-actions .tb{min-width:110px;justify-content:center}

/* responsive */
@media (max-width:1100px){
  .panel.left{width:210px;flex-basis:210px}
  .panel.right{width:300px;flex-basis:300px}
}
@media (max-width:860px){
  .panel.left{width:190px;flex-basis:190px}
  .panel.right{width:280px;flex-basis:280px}
  .brand-sub{display:none}
}
@media (max-width:700px){
  .panel.left{display:none}
}