/* Brick 38 · Step 06: read-only controller engineering rules. Theme variables shared with Steps 1–5. */
.nb-step06-page .nb-step06-hero{display:grid;grid-template-columns:38.2114% minmax(0,1fr);gap:0;min-width:0;margin-top:12px}
.nb-step06-page .nb-step06-symbol{padding:clamp(14px,2vw,29px);background:var(--nb-wash);border:1px solid var(--nb-rule);border-radius:8px;min-height:320px;display:flex;flex-direction:column;justify-content:space-between;gap:13px;min-width:0}
.nb-step06-page .nb-step06-symbol-head{display:flex;align-items:center;gap:12px;justify-content:space-between}
.nb-step06-page .nb-step06-symbol-head strong{font:500 clamp(2.5rem,7vw,7rem)/1 Georgia,serif;letter-spacing:-.05em}
.nb-step06-page .nb-step06-symbol svg{width:100%;max-width:430px;align-self:center;fill:transparent;color:var(--text-color);stroke:var(--text-color)}
.nb-step06-page .nb-step06-symbol svg rect{fill:var(--page-background-color);stroke:currentColor;stroke-width:1.4}
.nb-step06-page .nb-step06-flow-text{text-anchor:middle;stroke:none;fill:var(--text-color);font:700 15px 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-step06-flow-text .nb-flow-mini{font:500 10px 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-flow-foot{fill:var(--text-color);stroke:none;font:650 10px 'Segoe UI',Arial,sans-serif;letter-spacing:1.1px}
.nb-step06-page .nb-step06-lead{padding:clamp(22px,4vw,68px);display:flex;flex-direction:column;justify-content:center;min-width:0}
.nb-step06-page .nb-step06-lead h1{margin:.5em 0 .25em}
.nb-step06-page .nb-step06-lead p:not(.nb-deck){max-width:66ch;font-size:.91rem;line-height:1.65}
.nb-step06-page .nb-step06-anchor{display:flex;flex-wrap:wrap;align-items:center;gap:12px 19px;margin-top:17px;font:600 .82rem 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-step06-rule-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
.nb-step06-page .nb-step06-rule{min-width:0;padding:clamp(17px,2.7vw,29px);border:1px solid var(--nb-rule);border-radius:9px;background:var(--nb-wash)}
.nb-step06-page .nb-step06-index{font:700 .72rem/1.4 'Segoe UI',Arial,sans-serif;letter-spacing:.12em}
.nb-step06-page .nb-step06-rule h3,.nb-step06-page .nb-step06-strategies h3{font:500 clamp(1.35rem,2.1vw,2.1rem)/1.17 Georgia,serif;margin:14px 0 12px;letter-spacing:-.025em}
.nb-step06-page .nb-step06-rule p,.nb-step06-page .nb-step06-strategies p{font-size:.9rem;line-height:1.65;margin:0}
.nb-step06-page .nb-step06-boundary{padding:13px 16px;margin:18px 0 0;background:var(--nb-wash);border-left:4px solid var(--nb-ink);font-size:.83rem;line-height:1.65}
.nb-step06-page .nb-step06-strategies{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.nb-step06-page .nb-step06-strategies article{min-width:0;padding:21px 20px 19px;border:1px solid var(--nb-rule);border-radius:8px;display:flex;flex-direction:column;gap:0}
.nb-step06-page .nb-step06-strategies article h3{margin:10px 0}
.nb-step06-page .nb-step06-strategies a{margin-top:auto;padding-top:20px;font:700 .8rem/1.5 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-step06-selection{border-left:3px solid var(--nb-ink);background:var(--nb-wash);padding:12px 15px;font:600 .83rem/1.55 'Segoe UI',Arial,sans-serif;margin:0 0 12px}
.nb-step06-page .nb-step06-reference{border:1px solid var(--nb-rule);border-radius:8px;padding:0;background:var(--page-background-color)}
.nb-step06-page .nb-step06-reference summary{cursor:pointer;padding:15px 17px;font:700 .9rem/1.45 'Segoe UI',Arial,sans-serif;display:flex;gap:12px;align-items:center;justify-content:space-between}
.nb-step06-page .nb-step06-reference summary span{font-size:1.2rem;line-height:1}
.nb-step06-page .nb-step06-ref-inner{padding:0 17px 18px;border-top:1px solid var(--nb-rule)}
.nb-step06-page .nb-step06-ref-inner label{display:block;margin:16px 0 7px;font:700 .76rem/1.45 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-step06-ref-inner select{width:min(100%,500px);padding:11px;border:1px solid var(--nb-rule);border-radius:5px;color:var(--text-color);background:var(--page-background-color);font:500 .84rem 'Segoe UI',Arial,sans-serif}
.nb-step06-page .nb-step06-limits{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px;margin:19px 0}
.nb-step06-page .nb-step06-limits div{border:1px solid var(--nb-rule);background:var(--nb-wash);border-radius:7px;padding:14px;min-width:0}
.nb-step06-page .nb-step06-limits span{display:block;font:650 .71rem/1.4 'Segoe UI',Arial,sans-serif;min-height:35px}
.nb-step06-page .nb-step06-limits strong{font:500 clamp(1.15rem,2.1vw,1.9rem)/1.4 Georgia,serif;overflow-wrap:anywhere}
.nb-step06-page .nb-step06-ref-note{font-size:.81rem;line-height:1.65;max-width:106ch}
.nb-step06-page .nb-step06-trail{display:flex;flex-wrap:wrap;justify-content:space-between;gap:12px;padding-top:20px;border-top:1px solid var(--nb-rule);font-size:.88rem;margin-top:27px}
.nb-step06-page .nb-step06-trail span{opacity:.72}
.nb-step06-page input:focus-visible,.nb-step06-page select:focus-visible,.nb-step06-page summary:focus-visible{outline:3px solid currentColor;outline-offset:3px}
@media(max-width:920px){.nb-step06-page .nb-step06-hero{grid-template-columns:minmax(0,1fr)}.nb-step06-page .nb-step06-symbol{min-height:0}.nb-step06-page .nb-step06-symbol svg{height:140px}.nb-step06-page .nb-step06-lead{padding:25px}.nb-step06-page .nb-step06-strategies{grid-template-columns:minmax(0,1fr)}}
@media(max-width:670px){.nb-step06-page .nb-step06-rule-grid{grid-template-columns:minmax(0,1fr)}.nb-step06-page .nb-step06-limits{grid-template-columns:repeat(2,minmax(0,1fr))}.nb-step06-page .nb-step06-rule h3{margin:8px 0}.nb-step06-page .nb-step06-lead{padding:18px}}
@media(max-width:380px){.nb-step06-page .nb-step06-limits{grid-template-columns:minmax(0,1fr)}}