:root{--ink:#18241f;--muted:#647069;--paper:#fbfaf4;--surface:#fff;--line:#d9ded8;--green:#176b54;--green-dark:#0c4938;--green-soft:#e3f0e9;--coral:#d45f43;--yellow:#f3ca52;--blue:#2d6f9f;--radius:14px;--shadow:0 12px 36px rgba(24,36,31,.08)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:linear-gradient(rgba(24,36,31,.025) 1px,transparent 1px),linear-gradient(90deg,rgba(24,36,31,.025) 1px,transparent 1px),var(--paper);background-size:24px 24px;font-family:ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.65}button,input,select{font:inherit}a{color:var(--green-dark)}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--yellow);outline-offset:3px}.skip{position:absolute;top:-5rem;left:1rem;padding:.65rem 1rem;color:#fff;background:var(--ink);z-index:9}.skip:focus{top:1rem}.shell{width:min(1120px,calc(100% - 2rem));margin:auto}.hero{padding:4.5rem 0 3.2rem;color:#fff;background:var(--green-dark);border-bottom:7px solid var(--yellow)}.hero h1{max-width:900px;margin:0;font:500 clamp(2.7rem,7vw,5.5rem)/.98 Georgia,"Times New Roman",serif;letter-spacing:-.045em}.hero p{max-width:720px;margin:1.35rem 0 0;color:#dbece5;font-size:clamp(1.05rem,2vw,1.25rem)}.stats,.tags{display:flex;flex-wrap:wrap;gap:.55rem;margin-top:1.4rem}.pill{padding:.42rem .7rem;border-radius:999px;background:var(--green-soft);font-size:.82rem;font-weight:750}.stats .pill{color:var(--ink);background:var(--yellow);border-radius:6px}.library{padding:2.5rem 0 5rem}.finder{padding:1.2rem;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.finder-grid{display:grid;grid-template-columns:1fr 220px;gap:.9rem}.field label{display:block;margin-bottom:.35rem;font-size:.82rem;font-weight:800}.field input,.field select{width:100%;padding:.72rem .8rem;color:var(--ink);background:#fff;border:1px solid #aeb8b1;border-radius:8px}.timeline-title{display:flex;align-items:end;justify-content:space-between;margin:2.4rem 0 1rem}.timeline-title h2{margin:0;font:500 2rem/1.1 Georgia,serif}.cards{display:grid;gap:1rem}.card{display:grid;grid-template-columns:145px 1fr auto;gap:1.2rem;align-items:start;padding:1.35rem;background:var(--surface);border:1px solid var(--line);border-left:7px solid var(--green);border-radius:var(--radius);box-shadow:var(--shadow)}.card time{font-weight:800;color:var(--coral)}.card h3{margin:.1rem 0 .3rem;font:500 1.6rem/1.15 Georgia,serif}.card p{margin:.25rem 0;color:var(--muted)}.open{align-self:center;white-space:nowrap;padding:.65rem .9rem;text-decoration:none;font-weight:800;color:#fff;background:var(--green-dark);border-radius:8px}.hidden{display:none!important}.lesson-nav{padding:1rem 0;background:#fff;border-bottom:1px solid var(--line)}.lesson-nav a{text-decoration:none;font-weight:800}.lesson-hero{padding:3.7rem 0 2.6rem;color:#fff;background:var(--green-dark);border-bottom:7px solid var(--yellow)}.lesson-hero h1{max-width:870px;margin:.4rem 0;font:500 clamp(2.5rem,6vw,4.8rem)/1 Georgia,serif;letter-spacing:-.035em}.lesson-hero .question{max-width:760px;color:#dbece5;font-size:1.15rem}.lesson{width:min(900px,calc(100% - 2rem));margin:2.5rem auto 5rem}.section{margin:0 0 1.25rem;padding:1.5rem;background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.section h2{margin:0 0 1rem;font:500 1.7rem/1.15 Georgia,serif}.section h3{margin:1.25rem 0 .4rem;color:var(--green-dark)}.section p,.section li{max-width:76ch}.formula{margin:1rem 0;padding:1rem;text-align:center;font:600 clamp(1.15rem,3vw,1.55rem)/1.5 Georgia,serif;background:var(--green-soft);border-left:5px solid var(--green)}.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:.7rem}.step{padding:1rem;background:#f6f7f2;border-top:4px solid var(--coral)}.step strong{display:block;font-size:1.4rem;color:var(--coral)}.compare{width:100%;border-collapse:collapse}.compare th,.compare td{padding:.7rem;text-align:left;border-bottom:1px solid var(--line)}.practice details{margin:.7rem 0;padding:.8rem 1rem;background:#f6f7f2;border-radius:8px}.practice summary{cursor:pointer;font-weight:750}.golden-demo{display:grid;grid-template-columns:1fr 1fr;gap:1rem;align-items:center}.spiral-box{position:relative;aspect-ratio:1.618;border:4px solid var(--yellow);background:linear-gradient(90deg,transparent 61.8%,rgba(243,202,82,.24) 61.8%)}.spiral-box:after{content:"1 : 1.618";position:absolute;right:1rem;bottom:.7rem;font-weight:900;color:var(--green-dark)}footer{padding:2rem;color:var(--muted);text-align:center;border-top:1px solid var(--line)}@media(max-width:720px){.finder-grid,.card,.golden-demo{grid-template-columns:1fr}.card{border-left-width:5px}.open{justify-self:start}.steps{grid-template-columns:1fr 1fr}.hero{padding-top:3rem}}@media(prefers-reduced-motion:no-preference){.card{transition:transform .18s ease,box-shadow .18s ease}.card:hover{transform:translateY(-2px);box-shadow:0 16px 42px rgba(24,36,31,.12)}}