/* ===== Foam Mold Engineer — shared stylesheet (light, file:// safe) ===== */
:root{
  --bg:#f5f7fa; --panel:#ffffff; --ink:#1f2933; --muted:#5b6b7b;
  --line:#d8e0e8; --brand:#0b6e99; --brand2:#0a8f5b; --accent:#d94f1e;
  --warn:#b5651d; --shadow:0 1px 3px rgba(20,40,60,.12);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:"Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,"Noto Sans",sans-serif;
  background:var(--bg); color:var(--ink); font-size:15px; line-height:1.5;
}
a{color:var(--brand);text-decoration:none}
a:hover{text-decoration:underline}

/* Header — two-row classic Windows layout: title row + full-width menu bar */
#siteHeader{position:sticky;top:0;z-index:50;background:linear-gradient(180deg,#0b6e99,#0a5e83);
  color:#fff;box-shadow:var(--shadow)}
.hdr-top{max-width:1180px;margin:0 auto;display:flex;align-items:center;justify-content:space-between;
  gap:16px;padding:8px 16px 6px;flex-wrap:wrap}
.hdr-brand{font-weight:700;font-size:17px;display:flex;align-items:center;gap:8px;white-space:nowrap}
.hdr-logo{font-size:20px}
.hdr-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap}
.hdr-lang{display:flex;align-items:center;gap:6px;font-size:13px;color:#e9f4fa}
.hdr-lang select{background:#fff;color:var(--ink);border:1px solid var(--line);border-radius:6px;
  padding:4px 6px;font-size:13px}
.btn-home,.btn-mail{background:#fff;color:var(--brand);border:1px solid #fff;border-radius:8px;
  padding:5px 12px;font-size:13px;font-weight:600;white-space:nowrap}
.btn-home:hover,.btn-mail:hover{background:#e9f4fa;text-decoration:none}
.btn-mail{background:var(--brand2);color:#fff;border-color:var(--brand2)}
.btn-mail:hover{background:#0a7a4d}

/* Menu bar row (Windows menubar style): always horizontal, dropdowns below */
.hdr-menubar{display:flex;align-items:stretch;gap:2px;flex-wrap:nowrap;overflow-x:auto;
  background:rgba(0,0,0,.16);border-top:1px solid rgba(255,255,255,.14);padding:0 12px}
.hdr-menubar a,.hdr-menubar button{color:#e9f4fa;font-size:14px}
.nav-home{display:flex;align-items:center;padding:6px 12px;border-radius:0;white-space:nowrap}
.nav-home:hover{background:rgba(255,255,255,.15);text-decoration:none}
.nav-group{position:relative;display:flex;align-items:stretch}
.nav-top{background:none;border:0;font-family:inherit;padding:6px 12px;border-radius:0;
  cursor:pointer;white-space:nowrap}
.nav-top:hover,.nav-group.open .nav-top,.nav-group:focus-within .nav-top{background:rgba(255,255,255,.15)}
.nav-drop{display:none;position:absolute;top:100%;left:0;min-width:230px;z-index:60;
  background:#0a5e83;border:1px solid rgba(255,255,255,.25);border-top:0;
  box-shadow:0 8px 18px rgba(0,0,0,.28);padding:4px 0}
.nav-group.open>.nav-drop,.nav-group:hover>.nav-drop,.nav-group:focus-within>.nav-drop{display:block}
.nav-drop a{display:block;color:#e9f4fa;font-size:14px;padding:7px 16px;border-radius:0;white-space:nowrap}
.nav-drop a:hover{background:rgba(255,255,255,.15);text-decoration:none}
@media (max-width:900px){
  .hdr-menubar a,.hdr-menubar button{font-size:13px}
  .nav-home,.nav-top{padding:6px 9px}
  .hdr-top{gap:10px}
}

/* Layout */
main{max-width:1180px;margin:0 auto;padding:22px 16px 40px}
h1{font-size:24px;margin:6px 0 4px}
h2{font-size:18px;margin:18px 0 8px}
.tagline{color:var(--muted);margin:0 0 18px;font-size:15px}
.lead{color:var(--muted);margin:0 0 16px}

/* Home cards */
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:16px}
.card{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:16px 18px;
  box-shadow:var(--shadow);display:block;color:var(--ink)}
.card:hover{border-color:var(--brand);transform:translateY(-2px);transition:.15s;text-decoration:none}
.card h3{margin:0 0 6px;color:var(--brand);font-size:17px}
.card p{margin:0;color:var(--muted);font-size:14px}

/* Calculator grid */
.grid{display:grid;grid-template-columns:340px 1fr;gap:18px;align-items:start}
@media(max-width:880px){.grid{grid-template-columns:1fr}}
.panel{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:16px;
  box-shadow:var(--shadow)}
.panel h2{margin-top:0}

/* Form */
.field{display:flex;align-items:center;gap:8px;margin:8px 0}
.field label{flex:1;font-size:14px}
.field input,.field select{flex:0 0 120px;width:120px;padding:6px 8px;border:1px solid var(--line);
  border-radius:8px;font-size:14px;background:#fff;color:var(--ink)}
.field select{flex:0 0 140px;width:140px}
.field .u{color:var(--muted);font-size:13px;min-width:34px}
.actions{display:flex;gap:10px;margin-top:14px;flex-wrap:wrap}
.sample-bar{display:flex;align-items:center;gap:10px;flex-wrap:wrap;background:#eef6fb;
  border:1px solid #cfe6f2;border-radius:10px;padding:10px 12px;margin-bottom:14px}
.sample-bar label{font-weight:600;font-size:14px}
.sample-bar select{flex:0 0 auto;min-width:210px;padding:6px 8px;border:1px solid var(--line);
  border-radius:8px;font-size:14px;background:#fff;color:var(--ink)}
.sample-bar button{font-size:14px}
.toggle{display:inline-flex;align-items:center;gap:6px;margin-top:14px;font-size:13px;color:var(--muted);cursor:pointer;user-select:none}
.toggle input{width:16px;height:16px;accent-color:var(--brand);cursor:pointer}
button{font:inherit;cursor:pointer;border-radius:8px;padding:8px 14px;border:1px solid var(--line);
  background:#fff;color:var(--ink)}
button.primary{background:var(--brand);color:#fff;border-color:var(--brand)}
button.primary:hover{background:#0a5e83}
button.ghost{background:#f0f4f8}

/* Results */
.results dl{margin:0;display:grid;grid-template-columns:1fr auto;gap:0}
.results .row{display:contents}
.results dt{padding:7px 8px;border-top:1px solid var(--line);font-size:14px}
.results dd{padding:7px 8px;border-top:1px solid var(--line);text-align:right;font-variant-numeric:tabular-nums;
  font-weight:600;white-space:nowrap}
.results dd .sub{display:block;font-weight:400;color:var(--muted);font-size:12px}
.note{margin-top:10px;font-size:13px;color:var(--warn);background:#fff7ee;border:1px solid #f3d9b8;
  border-radius:8px;padding:8px 10px}

/* Schematic */
.schematic{margin-top:0}
.schematic svg{width:100%;height:auto;border:1px solid var(--line);border-radius:10px;background:#fff}
.sch-actions{display:flex;gap:10px;margin-top:10px}
.sch-actions button{font-size:13px;padding:6px 10px}

/* References */
.ref-list{display:grid;gap:14px}
.ref-item{background:var(--panel);border:1px solid var(--line);border-left:4px solid var(--brand);
  border-radius:10px;padding:12px 16px;box-shadow:var(--shadow)}
.ref-item h3{margin:0 0 6px;font-size:16px;color:var(--brand)}
.ref-item p{margin:0;color:var(--muted);font-size:14px}
.disclaimer{margin-top:18px;font-size:13px;color:var(--accent);background:#fdeee8;
  border:1px solid #f3c4b3;border-radius:8px;padding:10px 12px}

/* Footer */
footer{border-top:1px solid var(--line);background:#fff;margin-top:24px}
footer p{max-width:1180px;margin:0 auto;padding:14px 16px;color:var(--muted);font-size:13px}

/* Formula disclosure (polish) */
.formula{margin-top:14px;border:1px solid var(--line);border-radius:10px;background:#f7fafc;padding:0}
.formula summary{cursor:pointer;padding:8px 12px;font-size:13px;font-weight:600;color:var(--brand)}
.formula summary:hover{text-decoration:underline}
.formula p{margin:0;padding:0 12px 8px;font-size:13px;color:var(--ink);font-family:"Cambria Math","Segoe UI",system-ui,serif}
.formula p:last-child{padding-bottom:12px}

@media print{
  #siteHeader{position:static}
  .sch-actions,.hdr-actions,.hdr-menubar,.actions{display:none}
}

/* Process-summary list */
.sum-item{display:flex;align-items:center;justify-content:space-between;gap:12px;
  padding:10px 12px;border:1px solid var(--line);border-radius:8px;margin-bottom:8px;background:#fff}
.sum-item .chk{display:flex;align-items:center;gap:8px;font-size:14px;font-weight:600}
.sum-item .sum-name{color:var(--ink)}
.sum-item .sub{color:var(--muted);font-size:12px}
.results .empty{color:var(--muted);font-size:14px}

/* Tolerance inputs (L/W/H inline) + verdict warning + topology badge */
.tol-axes{display:inline-flex;flex-wrap:wrap;align-items:center;gap:6px}
.tol-axes .ax{font-weight:700;color:var(--muted);font-size:12px;margin-left:4px}
.tol-axes input{width:64px}
.warn{display:none;color:#9a3412;background:#fff1e6;border:1px solid #f0b27a;
  padding:8px 10px;border-radius:6px;font-size:13px;margin-top:10px}
.topo-badge{display:inline-block;margin-left:8px;padding:1px 8px;border-radius:10px;
  font-size:11px;font-weight:700;color:#0b6e99;background:#e7f2f8;border:1px solid #b9dcec}

/* Compare / diff (P2-A) */
.cmp-btn{font-size:12px;padding:4px 10px;border:1px solid var(--line);border-radius:8px;
  background:#f0f4f8;color:var(--brand);font-weight:600;margin-left:8px}
.cmp-btn.active{background:var(--brand);color:#fff;border-color:var(--brand)}
.diff{margin:6px 0 14px;padding:10px 12px;border:1px solid var(--line);border-radius:10px;
  background:#f7fafc;overflow-x:auto}
.diff-tbl{border-collapse:collapse;width:100%;font-size:13px}
.diff-tbl th,.diff-tbl td{border:1px solid var(--line);padding:5px 8px;text-align:left}
.diff-tbl th{background:#eef3f7;font-weight:700;color:#0b6e99}
.diff-tbl td:last-child,.diff-tbl th:last-child{text-align:right;font-variant-numeric:tabular-nums;white-space:nowrap}
.diff-tbl tr.chg td{background:#fff1e6}
.diff-tbl tr.chg td:last-child{color:#9a3412;font-weight:700}

/* Diff sub-sections: input parameters + results (P2-A update) */
.diff-sec{margin-bottom:12px}
.diff-sec h4{margin:0 0 6px;color:#0b6e99;font-size:13px;font-weight:700}

/* Help overlay (Direction-3 P1) */
.foam-overlay{position:fixed;inset:0;z-index:200;display:flex;align-items:center;
  justify-content:center;background:rgba(20,40,60,.45)}
.foam-modal{background:var(--panel);border:1px solid var(--line);border-radius:14px;
  box-shadow:0 8px 30px rgba(20,40,60,.25);max-width:640px;width:calc(100% - 32px);
  max-height:80vh;display:flex;flex-direction:column;overflow:hidden}
.foam-modal-hd{display:flex;align-items:center;justify-content:space-between;gap:12px;
  padding:12px 16px;border-bottom:1px solid var(--line)}
.foam-modal-hd h3{margin:0;font-size:17px;color:var(--brand)}
.foam-modal-bd{padding:14px 18px;overflow:auto;font-size:14px;line-height:1.6;color:var(--ink)}
.help-md p{margin:0 0 10px}
.help-md code{background:#eef4f8;border:1px solid var(--line);border-radius:5px;
  padding:1px 5px;font-family:"Cambria Math","Consolas",monospace;font-size:13px}
.help-md ul{margin:0 0 10px;padding-left:20px}