*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0}img,svg{max-width:100%}a{color:inherit}button,a{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible{outline:3px solid currentColor;outline-offset:5px}button{font:inherit}p,li,dd{line-height:1.65}p{}h1,h2,h3,p{margin-top:0}h1{overflow-wrap:anywhere}h2{line-height:1.12}ul,ol{padding-left:1.2em}.skip{position:absolute;top:-90px;left:1rem;z-index:20;padding:1rem;background:#fff;color:#111}.skip:focus{top:1rem}.call{display:inline-flex;align-items:center;justify-content:center;gap:.65rem;text-decoration:none;font-weight:800;min-height:3.1rem;padding:.8rem 1.1rem;border-radius:var(--call-radius,0);background:var(--call-bg,#17332e);color:var(--call-ink,#fff)}.call small{display:block;font-size:.73em;font-weight:500}.brand{display:flex;align-items:center;gap:.85rem;text-decoration:none;font-weight:700;max-width:34rem;line-height:1.25}.brand img{width:3.2rem;height:3.2rem;flex:none}.menu-toggle{display:none}.source-links{font-size:.9rem;display:flex;flex-wrap:wrap;gap:.6rem 1.4rem;padding-top:1.1rem}.site-footer{padding:3rem var(--gutter,5vw);font-size:.92rem}.site-footer h2{font-size:1.2rem}.site-footer address{font-style:normal;line-height:1.65}.listing{max-width:55rem}.listing p{margin:.65rem 0}.legal-note{font-size:.8rem;max-width:70rem;line-height:1.55}.footer-contact{font-weight:650}.chapter p{max-width:68ch}.chapter ul,.chapter ol{max-width:66ch}.chapter li{padding:.25rem 0}.worksheet{border-collapse:collapse;width:100%}.worksheet th,.worksheet td{padding:.8rem;text-align:left;border-bottom:1px solid currentColor;vertical-align:top}.worksheet th{font-size:.8rem;letter-spacing:.03em}.interactive-list{list-style:none;padding:0!important}.interactive-list button{width:100%;border:1px solid currentColor;background:transparent;color:inherit;text-align:left;padding:1rem;margin-bottom:.5rem;cursor:pointer}.interactive-list button:before{content:'□';margin-right:.7rem}.interactive-list button[aria-pressed=true]:before{content:'✓'}.interactive-list button[aria-pressed=true]{opacity:.7}.home-link{text-decoration:none}.page-kicker{text-transform:uppercase;letter-spacing:.15em;font-size:.7rem;font-weight:750}.hero-figure{margin:0}.hero-figure img{width:100%;height:auto}.hero-figure figcaption{font-size:.75rem;line-height:1.5}.article-cta{padding:1.2rem 0}.article-cta p{font-size:.9rem;max-width:52ch}.utility{min-height:50vh}.navigation-links a[aria-current=page]{font-weight:850;text-decoration-thickness:3px}.chapter a{overflow-wrap:anywhere}@media(max-width:720px){.menu-toggle{display:block;border:1px solid currentColor;background:transparent;color:inherit;padding:.55rem .8rem}.navigation-links{display:none!important}.navigation-open .navigation-links{display:flex!important;flex-direction:column!important;gap:.8rem!important;padding:1rem!important}.brand{font-size:.95rem}.worksheet{font-size:.82rem}.site-footer{padding:2.5rem 6vw}h1{font-size:clamp(2.6rem,11vw,4.8rem)!important}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}
.call strong{display:block;font-size:1.15rem;letter-spacing:.02em}.call small{font-size:.75rem;font-weight:600}

:root{--call-bg:#203e69;--call-ink:#fff;--call-radius:0}body{background:#fff;color:#203e69;font-family:Arial,sans-serif}.gruber-crisp-header{padding:1.4rem 6vw;display:flex;justify-content:space-between;align-items:center;gap:2rem}.gruber-crisp-header .brand{font:700 1.25rem Georgia,serif}.gruber-crisp-header section{display:flex;align-items:center;gap:.8rem}.gruber-double-rule-index{padding:1.1rem 9vw;border-block:5px double #203e69}.gruber-double-rule-index nav{display:grid;grid-template-columns:repeat(4,1fr);gap:.8rem 1.7rem;font:.74rem monospace}.gruber-double-rule-index a{text-decoration:none}.gruber-duplex-opening{padding:4rem 8vw;background:linear-gradient(90deg,#203e69 50%,#d5e8e5 50%);text-align:center}.gruber-duplex-opening .page-kicker{display:inline-block;background:#fff;padding:.6rem}.gruber-duplex-opening h1{font:400 clamp(4rem,6.4vw,7rem)/1.03 Georgia,serif;max-width:20ch;margin-inline:auto;background:#fff;padding:1.3rem}.gruber-duplex-opening .deck{max-width:62ch;margin-inline:auto;background:#fff;padding:1.3rem}.gruber-source-comparison{padding:3rem 8vw;border-bottom:2px solid #93b1bc}.gruber-source-comparison h2,.gruber-question-rail h2{font:400 2.8rem/1.1 Georgia,serif}.gruber-source-comparison .worksheet{font:.9rem Arial,sans-serif;background:#eff5f6}.gruber-source-comparison th{background:#203e69;color:#fff}.gruber-source-comparison td{border-color:#93b1bc}.gruber-explanation-rails{display:grid;grid-template-columns:1.4fr .85fr;gap:4rem;padding:3rem 8vw;background:#eff5f6;align-items:end}.gruber-question-rail{padding:2rem;border-left:6px solid #203e69;background:#fff}.gruber-lower-pair-view{max-width:31rem;border-top:6px solid #93b1bc;padding-top:1rem;margin-top:4rem}.gruber-official-join{padding:1rem 8vw;border-block:1px solid #93b1bc}.gruber-centered-call{padding:1rem 8vw 4rem;text-align:center}.gruber-centered-call p{margin-inline:auto}.gruber-footer-channels{display:grid;grid-template-columns:1.2fr 1fr;gap:0;padding:0}.gruber-dark-identity{padding:2rem 3vw 2rem 6vw;background:#203e69;color:#fff}.gruber-pale-contact{padding:3rem 6vw 2rem 3vw;background:#d5e8e5;align-self:stretch}.gruber-rejoined-note{grid-column:1/-1;padding:2rem 6vw;border-top:5px double #203e69}@media(max-width:850px){.gruber-crisp-header{display:block}.gruber-crisp-header section{margin-top:1rem}.gruber-double-rule-index{padding:.5rem 6vw}.gruber-duplex-opening{padding:2.5rem 6vw}.gruber-duplex-opening h1,.gruber-duplex-opening .deck{padding:.8rem}.gruber-source-comparison{padding:2rem 5vw}.gruber-explanation-rails{grid-template-columns:1fr;gap:1.5rem;padding:2rem 6vw}.gruber-question-rail{padding:1.5rem}.gruber-lower-pair-view{max-width:26rem;margin:0 auto}.gruber-footer-channels{grid-template-columns:1fr}.gruber-dark-identity,.gruber-pale-contact{padding:2rem 6vw}}
.call strong{white-space:nowrap;font-family:Arial,sans-serif}.call small{max-inline-size:24ch;white-space:normal}.call{max-inline-size:100%}@media(max-width:870px){:where(header,section,aside,div):has(>.call):has(>.menu-toggle){flex-wrap:wrap;min-inline-size:0;max-inline-size:100%;gap:.6rem}.call{flex-shrink:0;padding:.7rem .8rem}.menu-toggle{font-size:.85rem;padding:.55rem .65rem}}