.article-section.practice details{margin:1rem 0;padding:.9rem 1rem;border:1px solid var(--line,#d4e1dc);border-radius:.65rem;background:var(--white,#fff)}.article-section.practice summary{font-weight:750;cursor:pointer}.article-section.practice summary:focus-visible{outline:3px solid #087e76;outline-offset:4px}.article-section.practice .probe-invite{margin-bottom:0}.worksheet-space{min-height:8rem;border:1px dashed #8fa7a3;padding:1rem;margin:1.5rem 0;border-radius:.5rem}.worksheet-answers{margin:2rem 0;padding:1rem;border:1px solid #bfd5ce;border-radius:.5rem}.worksheet-answers summary{font-weight:700;cursor:pointer}.capability-table{min-width:38rem}
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.article-header{margin:1.25rem 0 2.25rem;max-width:none;align-items:flex-start;padding:clamp(1.3rem,3vw,2rem) clamp(1.2rem,3vw,2.2rem)}.article-header h1{color:#fff;margin:.1rem 0 .55rem;font-size:clamp(1.85rem,1.35rem + 2vw,2.7rem)}.article-header .lead{color:#fff;opacity:.95;font-weight:600}.article-header .icon-tile{width:60px;height:60px;margin-top:.2rem}.article-layout{display:grid;grid-template-columns:minmax(0,700px) minmax(0,260px);align-items:start;justify-content:space-between;gap:clamp(2rem,5vw,4.5rem);padding-bottom:var(--space)}.article-body{grid-column:1;grid-row:1;min-width:0;font-size:1.07rem;line-height:1.72}.article-body p,.article-body li,.prose p{max-width:68ch}.article-body ul,.article-body ol{padding-left:1.3rem;margin:0 0 1rem}.article-body li{margin:.3rem 0;padding-left:.2rem}.article-body li::marker{color:var(--primary);font-weight:800}
.summary{display:flex;gap:1rem;align-items:flex-start;background:var(--primary-soft);border:2px solid #a6e6dc;border-radius:var(--radius-lg);padding:1.2rem 1.4rem;box-shadow:0 var(--lip) 0 #a6e6dc}.summary h2{margin:0 0 .35rem;color:var(--primary-ink);font:800 .75rem/1.2 var(--font);letter-spacing:.08em;text-transform:uppercase}.summary p{margin:0;font-size:1.1rem;font-weight:700;color:var(--ink)}
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.references,.related{border-top:2px solid var(--line);margin-top:2.5rem}.references h2,.related h2{font-size:1.2rem;margin:1.5rem 0 .75rem}.references ul,.related ul{font-size:.98rem}.method-note{color:var(--ink-2);font-size:.92rem}
.toc{grid-column:2;grid-row:1;position:sticky;top:1.5rem;max-height:calc(100vh - 3rem);overflow-y:auto;border:2px solid var(--line);border-radius:var(--radius-lg);background:var(--bg);padding:1rem 1.1rem;font-size:.92rem;line-height:1.4;box-shadow:0 var(--lip) 0 var(--line)}.toc h2{margin:0 0 .6rem;color:var(--ink);font:800 .8rem/1.2 var(--font);letter-spacing:.08em;text-transform:uppercase}.toc ol,.toc-mobile ol{list-style:none;padding:0;margin:0}.toc ol{counter-reset:toc;position:relative}.toc ol::before{content:"";position:absolute;left:1.05rem;top:.9rem;bottom:.9rem;border-left:3px dotted var(--line-strong)}.toc li{margin:.1rem 0;position:relative}.toc li+li{counter-increment:toc}.toc a{display:flex;align-items:center;gap:.6rem;padding:.35rem .5rem .35rem 0;border-radius:10px;transition:transform .16s cubic-bezier(.34,1.56,.64,1),background .16s ease}.toc a::before{content:counter(toc);flex:none;position:relative;display:grid;place-items:center;width:1.6rem;height:1.6rem;margin-left:.25rem;border-radius:50%;background:var(--surface-2);color:var(--ink-2);font:800 .75rem/1 var(--font);box-shadow:0 2px 0 var(--line-strong)}.toc li:first-child a::before{content:"★";background:var(--gold);color:var(--ink);box-shadow:0 2px 0 var(--gold-edge)}.toc a:hover::before{background:var(--primary);color:#fff;box-shadow:0 2px 0 var(--primary-edge)}.toc a,.toc-mobile a{color:var(--ink-2);font-weight:700;text-decoration:none}.toc a:hover{color:var(--blue-ink);transform:translateX(3px)}.toc-mobile a:hover{color:var(--blue-ink);text-decoration:underline}.toc-mobile{display:none}
.probe-invite{display:flex;align-items:flex-end;gap:.9rem;margin:2.75rem 0 0;font-size:1rem;line-height:1.5}.probe-invite-art{flex:none;width:72px;height:72px}.probe-invite-body{position:relative;min-width:0;flex:1;padding:1.15rem 1.3rem;background:var(--bg);border:2px solid var(--line);border-radius:var(--radius-lg);box-shadow:0 var(--lip) 0 var(--line)}.probe-invite-body::before{content:"";position:absolute;left:-9px;bottom:22px;width:14px;height:14px;background:var(--bg);border-left:2px solid var(--line);border-bottom:2px solid var(--line);transform:rotate(45deg)}.probe-invite p{margin:0 0 .9rem;color:var(--ink);font-weight:800;font-size:1.05rem;max-width:none}.probe-invite-actions{display:flex;align-items:center;flex-wrap:wrap;gap:.75rem 1.1rem}.quiet-link{color:var(--blue-ink);font-size:.92rem}.page-intro .probe-invite{max-width:660px}
.feature-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1.1rem;padding:1rem 0 var(--space)}.feature-grid>div{background:var(--bg);border:2px solid var(--line);border-radius:var(--radius-lg);padding:1.3rem 1.35rem;box-shadow:0 var(--lip) 0 var(--line)}.feature-grid .icon-tile{margin-bottom:.9rem}.feature-grid h2{font-size:1.15rem;margin:0 0 .4rem}.feature-grid p{color:var(--ink-2);margin:0}.prose{padding:0 0 var(--space);font-size:1.07rem;line-height:1.72}.prose h2{margin-top:2rem}
.calculator-panel{background:var(--bg);border:2px solid var(--line);border-radius:var(--radius-lg);padding:clamp(1.1rem,3vw,1.75rem);box-shadow:0 var(--lip) 0 var(--line)}.calculator-panel h2{margin:0 0 .35rem;font-size:1.3rem}.calculator-panel>p{color:var(--ink-2)}.noscript-note{background:var(--gold-soft);border:2px solid var(--gold);border-radius:12px;padding:.6rem .85rem;font-size:.95rem}.calculator-panel form{margin:1.1rem 0 0}.calculator-panel fieldset{border:0;margin:0;padding:0;min-width:0}.calculator-panel legend{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}.calc-fields{display:grid;align-items:end;grid-template-columns:repeat(auto-fit,minmax(min(100%,190px),1fr));gap:1rem}.calculator-panel label{display:block;font-weight:800;font-size:.95rem;line-height:1.35;color:var(--ink)}.calc-mode{max-width:16rem;margin-bottom:1rem}.calculator-panel input,.calculator-panel select{display:block;background:var(--surface);color:var(--ink);border:2px solid var(--line-strong);border-radius:var(--radius);width:100%;min-height:50px;padding:.5rem .85rem;margin-top:.4rem;font-weight:700}.calculator-panel input:focus,.calculator-panel select:focus{border-color:var(--blue);background:var(--bg)}.calc-submit{margin-top:1.4rem}.calculator-panel button{min-height:50px;padding:0 1.8rem}.calculator-panel button:disabled{--btn-bg:var(--surface-2);--btn-edge:var(--line-strong);color:#b9c3c9;cursor:default;filter:none;transform:none}.calc-error,.calc-result{margin:0}.calc-error:not(:empty){margin-top:1.1rem;padding:.8rem 1rem;border:2px solid #ffb3b5;border-radius:var(--radius);background:var(--danger-soft);color:var(--danger-ink);font-weight:800}.calc-result:not(:empty){margin-top:1.1rem;background:var(--primary-soft);border:2px solid #a6e6dc;border-radius:var(--radius);padding:.9rem 1.1rem;font-weight:800;color:var(--primary-ink)}.calc-notes h2{font-size:1.2rem;margin:2.25rem 0 .5rem}.calc-notes p{max-width:68ch}.narrow>.tool-link{margin:2rem 0 var(--space)}.narrow>.probe-invite{margin-top:2rem}
.site-footer{border-top:2px solid var(--line);background:var(--surface)}.footer-inner{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:1rem 2rem;padding:2rem 0}.footer-inner strong{color:var(--primary);font-size:1.15rem;font-weight:800}.footer-inner p{margin:.15rem 0 0;color:var(--ink-2);font-size:.92rem}.footer-inner nav{display:flex;flex-wrap:wrap;gap:.4rem 1.25rem}.footer-inner nav a{font-size:.92rem;color:var(--ink-2);text-decoration:none}.footer-inner nav a:hover{color:var(--blue-ink);text-decoration:underline}
@keyframes probe-arrive{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}
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