:root{color-scheme:light;--font-sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--text: #111827;--muted: #475569;--subtle: #64748b;--bg: #f8fafc;--surface: #ffffff;--surface-alt: #eef7f1;--border: #d8e2dc;--border-strong: #94a3b8;--primary: #0f766e;--primary-strong: #115e59;--primary-soft: #ccfbf1;--blue: #1d4ed8;--yellow: #facc15;--success: #15803d;--warning: #b45309;--error: #b91c1c;--focus: #f59e0b;--radius: 8px;--shadow: 0 1px 2px rgb(15 23 42 / .08);--container: 1160px;--content: 74ch;--space-1: .25rem;--space-2: .5rem;--space-3: .75rem;--space-4: 1rem;--space-5: 1.5rem;--space-6: 2rem;--space-7: 3rem;--space-8: 4rem}*{box-sizing:border-box}html{font-family:var(--font-sans);line-height:1.5;background:var(--bg);color:var(--text);text-size-adjust:100%}body{margin:0;min-width:320px}body,button,input,select,textarea{font:inherit}img,svg{max-width:100%}img{height:auto}a{color:var(--primary-strong);text-underline-offset:.16em}a:hover{color:var(--blue)}button,a{touch-action:manipulation}:focus-visible{outline:3px solid var(--focus);outline-offset:3px}::selection{background:var(--primary-soft)}.skip-link{position:fixed;inset-block-start:var(--space-3);inset-inline-start:var(--space-3);z-index:20;transform:translateY(-150%);background:var(--text);color:#fff;padding:var(--space-2) var(--space-3);border-radius:var(--radius)}.skip-link:focus{transform:translateY(0)}.site-shell{min-height:100vh;display:flex;flex-direction:column}.site-main{flex:1}.container{width:min(100% - 2rem,var(--container));margin-inline:auto}.content-width{max-width:var(--content)}.section{padding-block:var(--space-7)}.section-tight{padding-block:var(--space-5)}.band{background:var(--surface);border-block:1px solid var(--border)}.eyebrow{color:var(--primary-strong);font-weight:750;font-size:.9rem;text-transform:uppercase;letter-spacing:0}h1,h2,h3{line-height:1.12;letter-spacing:0;margin-block:0 var(--space-3)}h1{font-size:clamp(2.15rem,1.5rem + 2vw,4rem);max-width:13ch}h2{font-size:clamp(1.55rem,1.25rem + 1vw,2.35rem)}h3{font-size:1.18rem}p{margin-block:0 var(--space-4)}ul,ol{padding-inline-start:1.25rem}li+li{margin-block-start:var(--space-2)}.lead{font-size:clamp(1.06rem,1rem + .25vw,1.25rem);color:var(--muted)}.muted{color:var(--muted)}.small{font-size:.92rem}.grid{display:grid;gap:var(--space-4)}.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}.grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:var(--space-5)}.card h3 a{text-decoration:none}.button-row{display:flex;flex-wrap:wrap;gap:var(--space-3);align-items:center}.button{display:inline-flex;align-items:center;justify-content:center;gap:var(--space-2);min-height:46px;border:1px solid transparent;border-radius:var(--radius);padding:.72rem 1rem;font-weight:750;text-decoration:none;cursor:pointer}.button-primary{background:var(--primary);color:#fff}.button-primary:hover{background:var(--primary-strong);color:#fff}.button-secondary{background:var(--surface);color:var(--primary-strong);border-color:var(--border-strong)}.button-quiet{background:transparent;color:var(--primary-strong);border-color:transparent}.badge{display:inline-flex;align-items:center;min-height:1.8rem;border-radius:999px;padding:.2rem .65rem;background:var(--surface-alt);color:var(--primary-strong);border:1px solid var(--border);font-size:.85rem;font-weight:700}.stat-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:var(--space-3)}.stat{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:var(--space-4)}.stat strong{display:block;font-size:1.6rem}.callout{border-inline-start:4px solid var(--primary);background:var(--surface-alt);padding:var(--space-4);border-radius:0 var(--radius) var(--radius) 0}.site-header{background:#f8fafcf5;border-block-end:1px solid var(--border);position:sticky;top:0;z-index:10;backdrop-filter:blur(12px)}.header-inner{min-height:70px;display:flex;align-items:center;justify-content:space-between;gap:var(--space-4)}.brand{display:inline-flex;align-items:center;gap:var(--space-2);color:var(--text);font-weight:850;text-decoration:none}.brand-mark{display:inline-grid;place-items:center;inline-size:38px;block-size:38px;border-radius:var(--radius);background:var(--primary);color:#fff;font-weight:900}.site-nav{display:flex;align-items:center;justify-content:flex-end;gap:var(--space-2);flex-wrap:wrap}.site-nav a{color:var(--text);text-decoration:none;font-weight:700;padding:var(--space-2) var(--space-3);border-radius:var(--radius)}.site-nav a[aria-current=page],.site-nav a:hover{background:var(--surface-alt);color:var(--primary-strong)}.site-footer{background:#0f172a;color:#e2e8f0;padding-block:var(--space-7)}.site-footer a{color:#d1fae5}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:var(--space-6)}.footer-links{list-style:none;padding:0;margin:0}.breadcrumbs{font-size:.92rem;color:var(--muted);padding-block:var(--space-4)}.breadcrumbs ol{list-style:none;padding:0;margin:0;display:flex;gap:var(--space-2);flex-wrap:wrap}.breadcrumbs li:not(:last-child):after{content:"/";color:var(--subtle);margin-inline-start:var(--space-2)}.hero{padding-block:var(--space-8) var(--space-7);background:linear-gradient(135deg,rgb(15 118 110 / .1),transparent 42%),linear-gradient(0deg,#fff,#f8fafc);border-block-end:1px solid var(--border)}.hero-grid{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(280px,.75fr);gap:var(--space-7);align-items:center}.hero-panel{border:1px solid var(--border);background:var(--surface);border-radius:var(--radius);padding:var(--space-5);box-shadow:var(--shadow)}.mini-road{inline-size:100%;aspect-ratio:4 / 3}.toc{border:1px solid var(--border);border-radius:var(--radius);padding:var(--space-4);background:var(--surface)}.toc a{text-decoration:none}.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:var(--space-6);align-items:start}.article-body{max-width:var(--content)}.article-body h2{margin-block-start:var(--space-6)}.sidebar{position:sticky;top:90px;display:grid;gap:var(--space-4)}.source-list{list-style:none;padding:0}.source-list li{border-block-start:1px solid var(--border);padding-block:var(--space-3)}.faq{display:grid;gap:var(--space-3)}.faq details{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:var(--space-4)}.faq summary{cursor:pointer;font-weight:750}.road-sign-card{display:grid;gap:var(--space-3);text-decoration:none;color:var(--text)}.road-sign-card:hover h3{color:var(--primary-strong)}.sign-figure{display:grid;place-items:center;min-height:150px;background:#f1f5f9;border-radius:var(--radius);border:1px solid var(--border)}.ad-slot{min-height:var(--ad-height, 120px);border:1px dashed var(--border-strong);background:repeating-linear-gradient(45deg,#f8fafc,#f8fafc 12px,#eef2f7 12px 24px);display:grid;place-items:center;color:var(--muted);border-radius:var(--radius);padding:var(--space-4);text-align:center}.progress-bar{background:#e2e8f0;border-radius:999px;min-height:10px;overflow:hidden}.progress-bar span{display:block;inline-size:var(--value, 0%);block-size:10px;background:var(--primary)}.quiz-shell{display:grid;gap:var(--space-5)}.quiz-panel{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:clamp(1rem,3vw,2rem);box-shadow:var(--shadow)}.quiz-topline{display:flex;align-items:center;justify-content:space-between;gap:var(--space-4);flex-wrap:wrap}.answer-list{display:grid;gap:var(--space-3);margin-block:var(--space-5)}.answer-option{width:100%;min-height:58px;display:grid;grid-template-columns:auto 1fr;align-items:center;gap:var(--space-3);border:2px solid var(--border);border-radius:var(--radius);background:var(--surface);color:var(--text);padding:var(--space-4);text-align:start;cursor:pointer}.answer-option:hover,.answer-option[aria-pressed=true]{border-color:var(--primary);background:var(--surface-alt)}.answer-option[data-state=correct]{border-color:var(--success);background:#ecfdf5}.answer-option[data-state=incorrect]{border-color:var(--error);background:#fef2f2}.answer-key{inline-size:2rem;block-size:2rem;display:inline-grid;place-items:center;border-radius:999px;background:#e2e8f0;font-weight:850}.feedback{border-radius:var(--radius);border:1px solid var(--border);padding:var(--space-4);background:#f8fafc}.feedback[data-tone=success]{border-color:var(--success);background:#ecfdf5}.feedback[data-tone=error]{border-color:var(--error);background:#fef2f2}.question-image{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;background:#f1f5f9;margin-block:var(--space-4)}.result-list{display:grid;gap:var(--space-4)}.hidden{display:none!important}.visually-hidden{position:absolute;inline-size:1px;block-size:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}@media(max-width:900px){.grid-2,.grid-3,.grid-4,.hero-grid,.article-layout,.footer-grid{grid-template-columns:1fr}.sidebar{position:static}.header-inner{align-items:flex-start;flex-direction:column;padding-block:var(--space-3)}.site-nav{justify-content:flex-start}h1{max-width:100%}.stat-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:560px){.container{width:min(100% - 1rem,var(--container))}.section{padding-block:var(--space-6)}.button,.button-row>*{width:100%}.site-nav a{padding-inline:var(--space-2)}.stat-grid{grid-template-columns:1fr}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;scroll-behavior:auto!important;transition-duration:.01ms!important}}