/* Z Score Tables — design system */
:root{
  --navy:#102a4a; --navy2:#1d4066; --blue:#2f5aa8; --blue-soft:#e8effa;
  --gold:#f59e0b; --gold-soft:#fef3c7; --ink:#1c2733; --mut:#5a6a7d;
  --line:#d7e0ec; --bg:#f6f8fb; --card:#ffffff; --green:#0e7a5f; --green-soft:#e2f4ee;
  --radius:14px; --shadow:0 6px 24px rgba(16,42,74,.08);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.65;font-size:17px}
a{color:var(--blue);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto}

/* header */
.site-head{position:sticky;top:0;z-index:50;background:var(--navy);display:flex;align-items:center;gap:18px;
  padding:10px 22px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:11px;color:#fff}
.brand:hover{text-decoration:none}
.brand-name{font-size:21px;letter-spacing:.2px;color:#dbe7f7}
.brand-name strong{color:#fff}
.main-nav{display:flex;gap:4px;flex-wrap:wrap;margin-left:auto}
.main-nav a{color:#c9d9ef;padding:7px 11px;border-radius:9px;font-size:15.5px;white-space:nowrap}
.main-nav a:hover{background:var(--navy2);text-decoration:none;color:#fff}
.main-nav a.is-on{background:var(--blue);color:#fff}

/* page frame */
.page{max-width:1060px;margin:0 auto;padding:26px 20px 54px}
.crumbs{font-size:14px;color:var(--mut);margin-bottom:14px}
.crumbs a{color:var(--mut)}
h1{font-size:34px;line-height:1.2;color:var(--navy);margin:6px 0 10px;letter-spacing:-.3px}
h2{font-size:25px;color:var(--navy);margin:38px 0 10px;line-height:1.3}
h3{font-size:19.5px;color:var(--navy2);margin:26px 0 8px}
p{margin:10px 0}
.lede{font-size:19px;color:#33465e}
.small{font-size:14.5px;color:var(--mut)}
ul,ol{margin:10px 0 10px 22px;padding:0}
li{margin:5px 0}
strong{color:var(--navy)}
code{background:var(--blue-soft);padding:1px 6px;border-radius:6px;font-size:.92em}
.formula{background:var(--navy);color:#fff;border-radius:var(--radius);padding:18px 22px;font-size:21px;
  text-align:center;margin:18px 0;letter-spacing:.3px}
.formula .f-note{display:block;font-size:14.5px;color:#b9cde8;margin-top:6px;letter-spacing:0}
.answer-first{background:var(--green-soft);border-left:5px solid var(--green);border-radius:10px;
  padding:14px 18px;margin:16px 0}
.answer-first p{margin:4px 0}
.warn{background:#fdf0e3;border-left:5px solid var(--gold);border-radius:10px;padding:14px 18px;margin:16px 0}

/* tool zone */
.toolzone{background:var(--card);border:1px solid var(--line);border-radius:18px;box-shadow:var(--shadow);
  padding:20px;margin:20px 0 8px}
.finder-row{display:flex;flex-wrap:wrap;gap:9px;align-items:center}
.f-lab{font-weight:600;color:var(--navy);font-size:15.5px}
.finder input[type=text],.pvalue-box input[type=text],.pvalue-box select,.between-box input[type=text]{
  font-size:17px;padding:10px 12px;border:2px solid var(--line);border-radius:10px;width:170px;background:#fff;color:var(--ink)}
.finder input:focus,.pvalue-box input:focus,.between-box input:focus{border-color:var(--blue);outline:none}
.btn{background:#fff;border:2px solid var(--blue);color:var(--blue);font-weight:600;font-size:15.5px;
  padding:9px 16px;border-radius:10px;cursor:pointer}
.btn:hover{background:var(--blue-soft)}
.btn-primary{background:var(--blue);color:#fff}
.btn-primary:hover{background:var(--navy2)}
.btn-small{padding:6px 12px;font-size:14px}
.readout{display:grid;grid-template-columns:repeat(4,1fr) auto;gap:10px;margin:16px 0 6px;align-items:stretch}
.ro-item{background:var(--blue-soft);border-radius:11px;padding:9px 13px}
.ro-lab{display:block;font-size:12.5px;text-transform:uppercase;letter-spacing:.6px;color:var(--mut)}
.ro-item strong{font-size:21px;color:var(--navy)}
.shade-row,.convention{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin:12px 0 4px}
.chip{border:2px solid var(--line);background:#fff;border-radius:999px;padding:6px 14px;font-size:14.5px;
  font-weight:600;color:var(--navy);cursor:pointer}
.chip:hover{border-color:var(--blue)}
.chip.is-on{background:var(--gold);border-color:var(--gold);color:var(--navy)}
.curve{width:100%;height:auto;display:block;margin:6px 0}
.curveline{fill:none;stroke:var(--navy);stroke-width:2.6}
.shade-left{fill:rgba(47,90,168,.45)}
.shade-right{fill:rgba(245,158,11,.55)}
.shade-between{fill:rgba(14,122,95,.45)}
.axis,.tick{stroke:#93a7bf;stroke-width:1}
.ticklab{font-size:12px;fill:var(--mut);text-anchor:middle}
.meanline{stroke:var(--mut);stroke-width:1.4;stroke-dasharray:4 4}
.zline{stroke:#c2410c;stroke-width:2.4}
.meanlab{font-size:12.5px;fill:var(--mut);text-anchor:middle}
.between-box{display:flex;gap:9px;align-items:center;flex-wrap:wrap;border-top:1px dashed var(--line);
  padding-top:14px;margin-top:10px}
.between-out{flex-basis:100%;margin:6px 0 0;font-size:16.5px;color:var(--navy)}
.pvalue-box{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:18px 20px;margin:18px 0}

/* the tables */
.zt-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:12px;margin:14px 0;background:#fff}
table.zt{border-collapse:separate;border-spacing:0;width:100%;font-size:14.5px;font-variant-numeric:tabular-nums}
table.zt caption{text-align:left;font-weight:600;color:var(--navy);padding:11px 13px;font-size:15px}
table.zt th,table.zt td{padding:6px 8px;text-align:right;border-bottom:1px solid #edf1f7;white-space:nowrap}
table.zt thead th{position:sticky;top:0;background:var(--navy);color:#fff;z-index:3;text-align:right}
table.zt tbody th{position:sticky;left:0;background:var(--blue-soft);color:var(--navy);font-weight:700;
  text-align:right;z-index:2;border-right:2px solid var(--line)}
table.zt thead th:first-child{left:0;z-index:4;text-align:right}
table.zt td{cursor:pointer}
table.zt td.hl-row,table.zt td.hl-col{background:var(--gold-soft)}
table.zt td.hl-hover{background:#eef4ff}
table.zt td.pinned{background:var(--gold);color:var(--navy);font-weight:800;border-radius:4px}
table.zt tbody tr:hover td{background:#f2f7ff}
table.zt tbody tr:hover td.pinned{background:var(--gold)}
table.zt-pct td:first-child,table.zt-crit td{cursor:default}
table.zt-crit td,table.zt-crit th{text-align:left;padding:9px 12px;font-size:16px}
table.zt-unit td{font-size:13px}

/* content blocks */
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(215px,1fr));gap:13px;margin:16px 0}
.card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:16px 18px;color:var(--ink);box-shadow:var(--shadow)}
.card:hover{text-decoration:none;border-color:var(--blue)}
.card h3{margin:0 0 5px;font-size:18px;color:var(--blue)}
.card p{margin:0;font-size:15px;color:var(--mut)}
.steps{counter-reset:step;list-style:none;margin-left:0}
.steps li{counter-increment:step;position:relative;padding:10px 0 10px 52px;border-bottom:1px dashed var(--line)}
.steps li::before{content:counter(step);position:absolute;left:0;top:8px;width:36px;height:36px;border-radius:50%;
  background:var(--blue);color:#fff;font-weight:800;display:flex;align-items:center;justify-content:center;font-size:17px}
.example{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:16px 20px;margin:14px 0}
.example h3{margin-top:0}
.example .ans{background:var(--green-soft);border-radius:8px;padding:8px 13px;margin-top:9px}
details.faq{background:var(--card);border:1px solid var(--line);border-radius:11px;margin:9px 0;padding:4px 18px}
details.faq summary{cursor:pointer;font-weight:600;color:var(--navy);padding:11px 0;font-size:17px}
details.faq .faq-a{padding:0 0 13px}
details.practice{background:var(--card);border:1px solid var(--line);border-radius:11px;margin:9px 0;padding:4px 18px}
details.practice summary{cursor:pointer;font-weight:600;color:var(--navy);padding:11px 0}
.dl-strip{display:flex;gap:10px;flex-wrap:wrap;margin:16px 0}
.dl-strip a{display:inline-block;background:var(--navy);color:#fff;padding:11px 18px;border-radius:10px;font-weight:600}
.dl-strip a:hover{background:var(--navy2);text-decoration:none}
figure{margin:18px 0}
figure img{border:1px solid var(--line);border-radius:12px}
figcaption{font-size:14px;color:var(--mut);margin-top:7px}
.kv-strip{display:flex;gap:12px;flex-wrap:wrap;margin:16px 0}
.kv{background:var(--navy);color:#fff;border-radius:12px;padding:13px 18px;flex:1;min-width:170px}
.kv strong{display:block;font-size:23px;color:var(--gold)}
.kv span{font-size:14.5px;color:#c9d9ef}

/* footer */
.site-foot{background:var(--navy);color:#c9d9ef;margin-top:0;padding:40px 22px 30px}
.foot-grid{max-width:1060px;margin:0 auto;display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:22px}
.foot-col h3{color:#fff;font-size:16.5px;margin:0 0 10px}
.foot-col a{display:block;color:#c9d9ef;font-size:15px;padding:3px 0}
.foot-note,.foot-base{max-width:1060px;margin:22px auto 0;font-size:14px;color:#93a7bf}
.foot-note a{color:#c9d9ef}

@media (max-width:720px){
  body{font-size:16px}
  h1{font-size:27px}
  h2{font-size:22px}
  .readout{grid-template-columns:1fr 1fr}
  .readout .btn{grid-column:1/-1}
  .finder input[type=text]{width:140px;flex:1}
  .page{padding:20px 14px 44px}
  table.zt{font-size:13.5px}
  .main-nav{margin-left:0}
}
@media print{
  .site-head,.site-foot,.finder,.convention,.crumbs,.dl-strip,.no-print{display:none!important}
  body{background:#fff;font-size:12px}
  .page{max-width:none;padding:0}
  .zt-wrap{overflow:visible;border:none}
  table.zt td{cursor:default}
}