/* ForemanMath — shared styles.
   Layout: blueprint ground with faint drafting sketches; a paper "drawing sheet" holds each page;
   ad rails flank the sheet on wide screens, a leaderboard sits above the footer. */
:root{
  --ground:#1E4F8F;
  --ground-line:rgba(255,255,255,.10);
  --ground-line-major:rgba(255,255,255,.18);
  --sketch:rgba(255,255,255,.30);
  --sheet:#FCFBF7;
  --sheet-2:#F3F1EA;
  --ink:#1B2533;
  --ink-soft:#56616F;
  --rule:#D5DAE1;
  --accent:#1E4F8F;
  --redline:#B42318;
  --display:"Barlow Condensed","Arial Narrow",Arial,sans-serif;
  --body:"Barlow","Segoe UI",Helvetica,Arial,sans-serif;
  --mono:"IBM Plex Mono",ui-monospace,Menlo,Consolas,monospace;
  --hand:"Architects Daughter","Comic Sans MS",cursive;
  --shadow:0 1px 0 rgba(0,0,0,.04),0 18px 40px -18px rgba(5,20,45,.55);
  color-scheme:light;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --ground:#0D2445;--ground-line:rgba(170,200,255,.07);--ground-line-major:rgba(170,200,255,.13);--sketch:rgba(170,200,255,.22);
  --sheet:#151D29;--sheet-2:#1C2634;--ink:#E5EAF1;--ink-soft:#9AA6B6;--rule:#2B3747;
  --accent:#86B4F2;--redline:#F08A7E;color-scheme:dark}}
:root[data-theme="dark"]{
  --ground:#0D2445;--ground-line:rgba(170,200,255,.07);--ground-line-major:rgba(170,200,255,.13);--sketch:rgba(170,200,255,.22);
  --sheet:#151D29;--sheet-2:#1C2634;--ink:#E5EAF1;--ink-soft:#9AA6B6;--rule:#2B3747;
  --accent:#86B4F2;--redline:#F08A7E;color-scheme:dark}

*{box-sizing:border-box}
[hidden]{display:none!important}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;
  background-color:var(--ground);
  background-image:
    linear-gradient(var(--ground-line-major) 1px,transparent 1px),
    linear-gradient(90deg,var(--ground-line-major) 1px,transparent 1px),
    linear-gradient(var(--ground-line) 1px,transparent 1px),
    linear-gradient(90deg,var(--ground-line) 1px,transparent 1px);
  background-size:120px 120px,120px 120px,24px 24px,24px 24px;
  color:var(--ink);font-family:var(--body);font-size:16px;line-height:1.55;
  padding-inline:16px;padding-block:28px 40px;
}
img,svg{max-width:100%}
a{color:var(--accent)}
.skip{position:absolute;left:-999px;top:8px;background:var(--sheet);color:var(--ink);padding:8px 12px;z-index:5}
.skip:focus{left:16px}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

.sketches{position:fixed;inset:0;pointer-events:none;z-index:0;overflow:hidden}
.sketches svg{position:absolute;stroke:var(--sketch);fill:none;stroke-width:1.2}
.sketches text{fill:var(--sketch);stroke:none;font-family:var(--hand);font-size:13px}

.frame{position:relative;z-index:1;display:grid;grid-template-columns:minmax(0,960px);justify-content:center;gap:24px}
@media (min-width:1360px){.frame.has-rails{grid-template-columns:160px minmax(0,960px) 160px}}
.rail{display:none}
@media (min-width:1360px){.rail{display:block;position:sticky;top:calc(env(safe-area-inset-top,0px) + 24px);align-self:start}}

.sheet{background:var(--sheet);border:1px solid var(--rule);box-shadow:var(--shadow);min-width:0;position:relative}
.sheet::before{content:"";position:absolute;inset:8px;border:1px solid var(--rule);pointer-events:none}

/* Title block header */
.titleblock{display:grid;grid-template-columns:1fr auto;border-bottom:2px solid var(--ink);margin:8px 8px 0;position:relative}
.brand{display:flex;align-items:center;gap:14px;padding:16px 20px;text-decoration:none;color:var(--ink)}
.brand-mark{width:42px;height:42px;flex:none}
.brand-name{font-family:var(--display);font-weight:700;font-size:30px;letter-spacing:.02em;line-height:1;text-transform:uppercase}
.brand-name b{color:var(--accent);font-weight:700}
.brand-tag{font-size:13px;color:var(--ink-soft);margin-top:3px;letter-spacing:.02em}
.tb-cells{display:grid;grid-template-columns:repeat(3,auto);border-left:1px solid var(--ink)}
.tb-cell{padding:8px 14px;border-right:1px solid var(--rule);display:flex;flex-direction:column;justify-content:center;min-width:84px}
.tb-cell:last-child{border-right:0}
.tb-cell span{font-family:var(--display);font-size:11px;letter-spacing:.12em;text-transform:uppercase;color:var(--ink-soft)}
.tb-cell strong{font-family:var(--mono);font-weight:500;font-size:13px}
@media (max-width:720px){.titleblock{grid-template-columns:1fr}.tb-cells{border-left:0;border-top:1px solid var(--rule)}}

nav.crumbs{display:flex;gap:8px;align-items:center;padding:12px 28px 0;font-size:14px;color:var(--ink-soft);flex-wrap:wrap}
nav.crumbs a{text-decoration:none}
nav.crumbs a:hover{text-decoration:underline}

main{padding:20px 28px 32px}
@media (max-width:560px){main{padding:16px 18px 24px}nav.crumbs{padding-inline:18px}}

h1,h2,h3{font-family:var(--display);text-wrap:balance;line-height:1.1;margin:0}
h1{font-size:clamp(34px,5vw,48px);font-weight:700;text-transform:uppercase;letter-spacing:.01em}
h2{font-size:26px;font-weight:600;text-transform:uppercase;letter-spacing:.03em}
h3{font-size:19px;font-weight:600;letter-spacing:.02em}
p{margin:0;max-width:66ch}
.lede{font-size:18px;color:var(--ink-soft);margin-top:10px}

/* Home */
.hero{display:grid;gap:8px;padding-bottom:22px;border-bottom:1px solid var(--rule)}
.section-label{display:flex;align-items:center;gap:12px;margin:28px 0 14px}
.section-label h2{font-size:20px}
.section-label::after{content:"";flex:1;height:1px;background:var(--rule)}
.tools{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:14px}
.tool{display:grid;grid-template-rows:auto 1fr auto auto;gap:10px;padding:16px;border:1px solid var(--rule);background:var(--sheet);text-decoration:none;color:var(--ink);position:relative;transition:border-color .15s,transform .15s}
a.tool:hover,a.tool:focus-visible{border-color:var(--accent);transform:translateY(-2px);outline:none}
a.tool:focus-visible{box-shadow:0 0 0 3px color-mix(in srgb,var(--accent) 35%,transparent)}
.tool h3{font-size:21px}
.tool p{font-size:14px;color:var(--ink-soft);margin-top:4px}
.tool .go{font-family:var(--display);font-weight:600;font-size:14px;letter-spacing:.08em;text-transform:uppercase;color:var(--accent)}
.tool-icon{width:44px;height:44px;display:grid;place-items:center;border:1px solid var(--rule);background:var(--sheet-2);color:var(--accent)}
.tool-icon svg{width:28px;height:28px;stroke:currentColor;fill:none;stroke-width:1.5;stroke-linecap:round;stroke-linejoin:round}
.tool-tags{display:flex;flex-wrap:wrap;gap:6px;align-items:flex-start}
.tool-tags span{font-family:var(--mono);font-size:11px;color:var(--ink-soft);border:1px solid var(--rule);padding:1px 6px}
.finder{display:grid;gap:12px;margin-top:22px}
.search{display:flex;align-items:center;gap:10px;border:1px solid var(--rule);background:var(--sheet);padding:0 14px}
.search:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px color-mix(in srgb,var(--accent) 22%,transparent)}
.search svg{width:20px;height:20px;flex:none;stroke:var(--ink-soft);fill:none;stroke-width:2;stroke-linecap:round}
.search input{flex:1;min-width:0;border:0;background:transparent;color:var(--ink);font-family:var(--body);font-size:17px;padding:13px 0;outline:none}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chip{appearance:none;border:1px solid var(--rule);background:var(--sheet);color:var(--ink);font-family:var(--display);font-weight:600;font-size:14px;letter-spacing:.06em;text-transform:uppercase;padding:6px 14px;cursor:pointer}
.chip:hover{border-color:var(--accent)}
.chip[aria-pressed="true"]{background:var(--ink);border-color:var(--ink);color:var(--sheet)}
.chip:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.result-count{font-size:14px;color:var(--ink-soft);margin-top:10px;min-height:1.4em}
.empty{padding:28px;border:1px dashed var(--rule);text-align:center;color:var(--ink-soft);margin-top:20px}
.cred{display:grid;grid-template-columns:auto 1fr;gap:18px;align-items:start;margin-top:30px;padding:18px;background:var(--sheet-2);border-left:3px solid var(--ink)}
.cred svg{width:46px;height:46px;stroke:var(--ink);fill:none;stroke-width:1.6}
.cred p{margin-top:6px;color:var(--ink-soft)}
@media (max-width:480px){.cred{grid-template-columns:1fr}}

/* Calculator */
.calc{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,1fr);gap:22px;margin-top:22px;align-items:start}
@media (max-width:820px){.calc{grid-template-columns:1fr}}
.tabs{display:flex;flex-wrap:wrap;border-bottom:2px solid var(--ink);grid-column:1/-1}
.tab{appearance:none;border:1px solid var(--rule);border-bottom:0;background:var(--sheet-2);color:var(--ink-soft);font-family:var(--display);font-weight:600;font-size:16px;letter-spacing:.06em;text-transform:uppercase;padding:9px 16px;cursor:pointer;margin-right:-1px}
.tab[aria-selected="true"]{background:var(--ink);color:var(--sheet);border-color:var(--ink)}
.tab:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.panel{display:grid;gap:14px;align-content:start;min-width:0}
.fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
@media (max-width:420px){.fields{grid-template-columns:1fr}}
.field{display:grid;gap:4px;align-content:start;min-width:0}
.field.wide{grid-column:1/-1}
.field label{font-family:var(--display);font-weight:600;font-size:13px;letter-spacing:.1em;text-transform:uppercase;color:var(--ink-soft)}
.input-wrap{display:flex;align-items:stretch;border:1px solid var(--rule);background:var(--sheet);min-width:0}
.input-wrap:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px color-mix(in srgb,var(--accent) 22%,transparent)}
.input-wrap input,.input-wrap select{flex:1;min-width:0;width:100%;border:0;background:transparent;color:var(--ink);font-family:var(--mono);font-size:17px;padding:10px 12px;outline:none;font-variant-numeric:tabular-nums}
.input-wrap select{font-family:var(--body);font-size:16px;cursor:pointer}
.input-wrap select option{background:var(--sheet);color:var(--ink)}
.input-wrap .unit{display:flex;align-items:center;padding:0 12px;font-family:var(--mono);font-size:13px;color:var(--ink-soft);background:var(--sheet-2);border-left:1px solid var(--rule);white-space:nowrap}
.input-wrap.bad{border-color:var(--redline)}
.hint{font-size:13px;color:var(--ink-soft)}
.group-title{grid-column:1/-1;font-family:var(--display);font-weight:600;font-size:14px;letter-spacing:.12em;text-transform:uppercase;color:var(--ink);border-bottom:1px solid var(--rule);padding-bottom:4px;margin-top:4px}

.drawing{border:1px solid var(--rule);background:var(--sheet-2);padding:10px}
.drawing svg{width:100%;height:auto;display:block}
.drawing .obj{stroke:var(--ink);stroke-width:2;fill:none}
.drawing .thin{stroke:var(--ink-soft);stroke-width:1;fill:none}
.drawing .hatch{stroke:var(--ink-soft);stroke-width:.8}
.drawing .dim{stroke:var(--accent);stroke-width:1.1;fill:none}
.drawing .dimtxt{fill:var(--accent);font-family:var(--hand);font-size:15px}
.drawing .lbl{fill:var(--ink-soft);font-family:var(--display);font-size:12px;letter-spacing:.1em}
.drawing .fillsoft{fill:var(--sheet);stroke:var(--ink);stroke-width:1.5}

.results{border:2px solid var(--ink);background:var(--sheet);min-width:0}
.results-head{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:10px 14px;background:var(--ink);color:var(--sheet)}
.results-head h2{font-size:17px;letter-spacing:.12em;text-transform:uppercase}
.copy{appearance:none;border:1px solid currentColor;background:transparent;color:inherit;font-family:var(--display);font-weight:600;font-size:13px;letter-spacing:.08em;text-transform:uppercase;padding:4px 10px;cursor:pointer}
.copy:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.big{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,1fr));border-bottom:1px solid var(--rule)}
.big div{padding:14px;border-right:1px solid var(--rule);min-width:0}
.big div:last-child{border-right:0}
.big span{display:block;font-family:var(--display);font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--ink-soft)}
.big strong{font-family:var(--mono);font-weight:500;font-size:clamp(24px,3.6vw,32px);font-variant-numeric:tabular-nums;line-height:1.15;word-break:break-word}
.big em{font-style:normal;font-size:14px;color:var(--ink-soft);font-family:var(--mono)}
.table-wrap{overflow-x:auto}
table.out{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums}
table.out th,table.out td{padding:8px 14px;text-align:left;border-bottom:1px solid var(--rule);font-size:15px}
table.out th{font-family:var(--display);font-weight:600;font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--ink-soft)}
table.out td.n,table.out th.n{text-align:right}
table.out td.n{font-family:var(--mono)}
table.out tr:last-child td{border-bottom:0}
.advice{padding:10px 14px 14px;font-size:14px;color:var(--ink-soft);border-top:1px solid var(--rule)}
.advice.warn{color:var(--redline)}

.explain{display:grid;gap:26px;margin-top:34px}
.explain section{display:grid;gap:10px}
.explain h3{margin-top:4px}
.formula{font-family:var(--mono);font-size:14px;background:var(--sheet-2);border-left:3px solid var(--accent);padding:12px 14px;overflow-x:auto;white-space:pre;max-width:100%}
.ref{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums;max-width:640px}
.ref th,.ref td{padding:7px 12px;border-bottom:1px solid var(--rule);text-align:left;font-size:15px}
.ref th{font-family:var(--display);font-size:12px;letter-spacing:.12em;text-transform:uppercase;color:var(--ink-soft)}
dl.faq{display:grid;gap:14px;margin:0}
dl.faq dt{font-weight:600}
dl.faq dd{margin:4px 0 0;color:var(--ink-soft);max-width:66ch}
.tips{display:grid;gap:8px;padding-left:20px;margin:0}
.tips li{max-width:64ch}
.prose{display:grid;gap:14px}
.prose h2{margin-top:14px}
.prose ul{margin:0;padding-left:20px;display:grid;gap:6px}

/* Ads (preview placeholders only; hidden until AdSense is live) */
.ad{border:1.5px dashed color-mix(in srgb,var(--sheet) 60%,transparent);color:color-mix(in srgb,var(--sheet) 80%,transparent);display:grid;place-items:center;text-align:center;font-family:var(--display);font-size:12px;letter-spacing:.14em;text-transform:uppercase;background:color-mix(in srgb,var(--ground) 70%,#000 10%)}
.ad-rail{height:600px}
.ad-board{margin:0 8px 8px;height:90px;border-color:var(--rule);color:var(--ink-soft);background:var(--sheet-2)}
.ad-inline{height:100px;border-color:var(--rule);color:var(--ink-soft);background:var(--sheet-2);margin-top:26px}
@media (min-width:1360px){.has-rails .ad-inline{display:none}}

footer.foot{display:flex;flex-wrap:wrap;gap:8px 22px;justify-content:space-between;align-items:center;margin:0 8px 8px;padding:14px 20px;border-top:2px solid var(--ink);font-size:13px;color:var(--ink-soft)}
footer.foot nav{display:flex;flex-wrap:wrap;gap:16px}
footer.foot a{color:var(--ink-soft)}
.preview-flag{position:relative;z-index:1;max-width:960px;margin:0 auto 14px;color:#fff;font-size:13px;display:flex;gap:10px;align-items:center;opacity:.9}
.preview-flag span{font-family:var(--display);letter-spacing:.12em;text-transform:uppercase;border:1px solid rgba(255,255,255,.6);padding:1px 7px}

@media print{
  body{background:#fff;padding:0}
  .sketches,.rail,.ad,.preview-flag,.tabs,.copy,footer.foot nav,.related,.explain{display:none!important}
  .sheet{box-shadow:none;border:0}
  .calc{grid-template-columns:1fr}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}