:root{--ct-color-primary: #76232f;--ct-color-primary-contrast: #ffffff;--ct-color-accent: #76232f;--ct-color-bg: #ffffff;--ct-color-fg: #1a1a1a;--ct-color-muted: #6b6b6b;--ct-color-border: #d8d8d8;--ct-color-surface: #f7f7f7;--ct-color-pass: #2e7d32;--ct-color-marginal: #ef6c00;--ct-color-fail: #c62828;--ct-color-layer-bed: #8f693f;--ct-color-layer-height: #3f6991;--ct-color-layer-top: #913f69;--ct-font-display: "Montserrat", system-ui, -apple-system, "Segoe UI", sans-serif;--ct-font-body: "Open Sans", system-ui, -apple-system, "Segoe UI", sans-serif;--ct-space-1: .25rem;--ct-space-2: .5rem;--ct-space-3: .75rem;--ct-space-4: 1rem;--ct-space-6: 1.5rem;--ct-space-8: 2rem;--ct-page: 1100px;color-scheme:light}@media (prefers-color-scheme: dark){:root{color-scheme:dark;--ct-color-accent: #e8dedf;--ct-color-bg: #14161a;--ct-color-fg: #e6e6e6;--ct-color-muted: #a0a4ab;--ct-color-border: #333940;--ct-color-surface: #1c1f25;--ct-color-layer-bed: #c99a5e;--ct-color-layer-height: #6f9fd0;--ct-color-layer-top: #c9709c}}*{box-sizing:border-box}body{margin:0;background:var(--ct-color-bg);color:var(--ct-color-fg);font:16px/1.6 var(--ct-font-body)}main{max-width:44rem;margin:0 auto;padding:0 1.25rem 4rem}.masthead{background:var(--ct-color-primary);margin-bottom:2.5rem}.masthead-inner{display:flex;align-items:center;justify-content:space-between;gap:1rem;flex-wrap:wrap;max-width:44rem;margin:0 auto;padding:1.1rem 1.25rem}.wordmark{font-family:var(--ct-font-display);font-weight:650;letter-spacing:.01em;color:var(--ct-color-primary-contrast);text-decoration:none}.masthead-nav a{color:var(--ct-color-primary-contrast);text-decoration:none;font-size:.92rem;opacity:.9}.masthead-nav a:hover,.masthead-nav a:focus-visible{opacity:1;text-decoration:underline}h1{font-family:var(--ct-font-display);font-size:1.9rem;line-height:1.25;margin:0 0 .6rem}h2{font-family:var(--ct-font-display);font-size:1.15rem;margin:2rem 0 .5rem}.lede{font-size:1.1rem;color:var(--ct-color-muted);margin:0 0 1.5rem}.buy{display:flex;gap:1rem;align-items:center;flex-wrap:wrap;background:var(--ct-color-surface);border:1px solid var(--ct-color-border);border-radius:.6rem;padding:1rem 1.1rem}.price{font-weight:650;font-size:1.2rem}.cta{font:inherit;font-weight:600;color:var(--ct-color-primary-contrast);background:var(--ct-color-primary);border:0;border-radius:.4rem;padding:.6rem 1.1rem;cursor:pointer}.cta[disabled]{opacity:.55;cursor:progress}.cta-link{font-weight:600;color:var(--ct-color-accent)}.reassure{color:var(--ct-color-muted);font-size:.92rem}.chapter-list{list-style:none;padding:0;margin:1rem 0}.chapter-list li{display:flex;gap:.75rem;align-items:baseline;padding:.5rem 0;border-bottom:1px solid var(--ct-color-border)}.chapter-list .n{color:var(--ct-color-muted);font-variant-numeric:tabular-nums;min-width:1.5rem}.chapter-list .state{margin-left:auto;color:var(--ct-color-muted);font-size:.82rem;text-transform:uppercase;letter-spacing:.06em}.free{color:var(--ct-color-pass);font-weight:600}.crumb{color:var(--ct-color-muted);font-size:.9rem}.sec p{margin:0 0 1rem}.level1{background:var(--ct-color-surface);border:1px solid var(--ct-color-border);border-radius:.6rem;padding:.5rem 1.1rem 1rem}.note{color:var(--ct-color-muted);font-size:.92rem}.foot{border-top:1px solid var(--ct-color-border);margin-top:3rem}.foot-inner{max-width:44rem;margin:0 auto;padding:1.5rem 1.25rem 2rem;color:var(--ct-color-muted);font-size:.86rem}.foot-inner p{margin:0 0 .5rem}.foot-inner p:last-child{margin-bottom:0}.foot-inner a,a{color:var(--ct-color-accent)}.signin{display:flex;gap:.5rem;align-items:flex-end;flex-wrap:wrap;margin:1rem 0}.signin>div{display:flex;flex-direction:column}.signin label{display:block;font-size:.85rem;color:var(--ct-color-muted)}.signin input{font:inherit;padding:.5rem .6rem;border:1px solid var(--ct-color-border);border-radius:.35rem;background:var(--ct-color-bg);color:var(--ct-color-fg);min-width:16rem}.signin button{font:inherit;font-weight:600;padding:.55rem 1rem;border:0;border-radius:.35rem;background:var(--ct-color-primary);color:var(--ct-color-primary-contrast);cursor:pointer}.signin-msg,.quiz-msg{flex-basis:100%;margin:.4rem 0 0;color:var(--ct-color-muted);font-size:.9rem}.linkish{font:inherit;border:0;background:none;color:var(--ct-color-accent);padding:0;cursor:pointer;text-decoration:underline}.chapter-list li.passed .state{color:var(--ct-color-pass)}.chapter-list li.read .state{color:var(--ct-color-accent)}.chapter-list li.locked{color:var(--ct-color-muted)}.q{border:1px solid var(--ct-color-border);border-radius:.5rem;margin:1.25rem 0;padding:.75rem 1rem 1rem}.q legend{font-weight:600;padding:0 .35rem}.options{list-style:none;padding:0;margin:.5rem 0 0}.options li{padding:.2rem 0}.options label{display:flex;gap:.6rem;align-items:flex-start;cursor:pointer}.results{list-style:none;padding:0}.results li{border-left:3px solid var(--ct-color-border);padding:.4rem 0 .4rem .8rem;margin:.8rem 0}.results li.right{border-left-color:var(--ct-color-pass)}.results li.wrong{border-left-color:var(--ct-color-fail)}.q-stem{font-weight:600;margin:0 0 .2rem}.verdict{margin:0;font-size:.85rem;color:var(--ct-color-muted);text-transform:uppercase;letter-spacing:.05em}.why{margin:.3rem 0 0;color:var(--ct-color-muted)}.pass{color:var(--ct-color-pass);font-weight:600}.fail{color:var(--ct-color-fail);font-weight:600}.mark{margin:2rem 0 0}.certificate{border:1px solid var(--ct-color-border);border-radius:.6rem;padding:1.5rem 1.75rem}.cert-line{font-size:1.1rem;line-height:1.6;margin:0 0 1rem}.cert-holder{color:var(--ct-color-muted);font-size:.92rem;margin:0 0 1rem}.cpd{font-weight:600;margin:0 0 1rem}.covered h2{font-size:.85rem;text-transform:uppercase;letter-spacing:.06em;color:var(--ct-color-muted);margin:1.25rem 0 .4rem}.covered ol{margin:0;padding-left:1.3rem;color:var(--ct-color-muted);font-size:.94rem}.cert-ref{font-size:.86rem;color:var(--ct-color-muted);word-break:break-word;margin:1.25rem 0 .75rem}.cert-ref code{font-size:.95em}.certificate .note{font-size:.94rem;line-height:1.55;border-top:1px solid var(--ct-color-border);padding-top:.9rem}.download{display:flex;gap:.75rem;align-items:center;flex-wrap:wrap;margin:1.25rem 0 0}.download button{font:inherit;font-weight:600;padding:.55rem 1rem;border:0;border-radius:.35rem;background:var(--ct-color-primary);color:var(--ct-color-primary-contrast);cursor:pointer}.download button:disabled{opacity:.55;cursor:progress}.download .note{border:0;padding:0;font-size:.88rem}.fig{margin:1.5rem 0;padding:0}.fig svg{color:var(--ct-color-fg);max-width:100%}.fig figcaption{font-size:.9rem;color:var(--ct-color-muted);margin-top:.5rem}.calc-output{overflow-x:auto}.calc-output table{width:100%;border-collapse:collapse;font-size:.9rem;font-variant-numeric:tabular-nums}.calc-output th,.calc-output td{padding:.4rem .6rem;border-bottom:1px solid var(--ct-color-border);text-align:right}.calc-output thead th{border-bottom:2px solid var(--ct-color-border);font-weight:600;color:var(--ct-color-muted);text-transform:uppercase;font-size:.78rem;letter-spacing:.04em}.calc-output .ct-position-table th:nth-child(-n+3),.calc-output .ct-position-table td:nth-child(-n+3),.calc-output .ct-axial-table th:first-child,.calc-output .ct-axial-table td:first-child{text-align:left}.calc-output .ct-axial-table th:first-child{color:var(--ct-color-muted);font-weight:500}.calc-output tr.ct-row--layer-bed{background:#8f693f0f}.calc-output tr.ct-row--layer-height{background:#3f698f0f}.calc-output tr.ct-row--layer-top{background:#8f3f690f}.calc-output tr.ct-row--flagged td:first-child{color:var(--ct-color-fail);font-weight:600}.calc-output tr.ct-section-header td{background:var(--ct-color-surface);font-weight:600;font-size:.78rem;text-transform:uppercase;letter-spacing:.04em;color:var(--ct-color-muted);text-align:left}.calc-output .ct-table-footnote:empty{display:none}.calc-output .ct-headline{display:flex;gap:.8rem;align-items:flex-start;padding:.9rem 1rem;background:var(--ct-color-surface);border:1px solid var(--ct-color-border);border-radius:.5rem}.calc-output .ct-headline__sentence{margin:0}.calc-output .ct-status{display:inline-block;padding:2px 10px;border-radius:999px;font-size:.78rem;font-weight:600;text-transform:uppercase;white-space:nowrap;color:var(--ct-color-primary-contrast)}.calc-output .ct-status--pass{background:var(--ct-color-pass)}.calc-output .ct-status--marginal{background:var(--ct-color-marginal)}.calc-output .ct-status--fail{background:var(--ct-color-fail)}.calc-output .ct-listener-panel{padding:.9rem 1rem;background:var(--ct-color-surface);border:1px solid var(--ct-color-border);border-radius:.5rem}.calc-output .ct-listener-flag{display:flex;gap:.6rem;align-items:center;padding:.4rem 0;border-bottom:1px solid var(--ct-color-border)}.calc-output .ct-listener-flag:last-child{border-bottom:none}.calc-output .ct-polarity-grid{display:grid;grid-template-columns:auto repeat(4,1fr);gap:.5rem .7rem;align-items:center;min-width:560px}.calc-output .ct-polarity-grid__row-label{font-weight:600;color:var(--ct-color-muted);font-size:.9rem}.calc-output .ct-polarity-grid__col-label{text-align:center;font-size:.8rem;color:var(--ct-color-muted);text-transform:uppercase;letter-spacing:.04em}.calc-output .ct-polarity-cell{background:var(--ct-color-bg);border:1px solid var(--ct-color-border);border-radius:4px;padding:.4rem}.calc-output .ct-polarity-cell svg{display:block;width:100%;height:48px}.callout{border-left:3px solid var(--ct-color-accent);background:var(--ct-color-surface);border-radius:0 .5rem .5rem 0;padding:.8rem 1rem;margin:1.25rem 0}.callout p{margin:0 0 .6rem}.callout p:last-child{margin-bottom:0}.callout-label{font-size:.78rem;text-transform:uppercase;letter-spacing:.08em;font-weight:650;color:var(--ct-color-accent)}.callout.mistake{border-left-color:var(--ct-color-fail)}.callout.mistake .callout-label{color:var(--ct-color-fail)}.key-numbers{border-collapse:collapse;width:100%;margin:1.25rem 0;font-size:.95rem}.key-numbers th,.key-numbers td{text-align:left;vertical-align:top;padding:.45rem .6rem;border-bottom:1px solid var(--ct-color-border)}.key-numbers th{font-weight:600;width:38%}.key-numbers td+td{color:var(--ct-color-muted);font-size:.88rem}.try{border:1px solid var(--ct-color-border);border-radius:.6rem;padding:.9rem 1.1rem;margin:1.5rem 0;background:var(--ct-color-surface)}.try h3{margin:0 0 .6rem;font-size:1.02rem}.try dl{margin:0;display:grid;grid-template-columns:auto 1fr;gap:.35rem .9rem}.try dt{font-weight:600;color:var(--ct-color-muted)}.try dd{margin:0}.video[hidden]{display:none}@media print{.masthead,.foot,.try,.video{display:none}.callout{border-left-color:#000;background:none}}