:root{color-scheme:dark;--bg:#090b0b;--panel:#121615;--text:#f0f2e9;--muted:#a5ada7;--line:#2b322e;--lime:#d6f589;--orange:#f3c38d;font-family:Arial,Helvetica,sans-serif;font-size:16px}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);line-height:1.65}button,a,input,textarea{touch-action:manipulation}button{font:inherit;color:inherit;cursor:pointer;background:transparent;border:1px solid var(--line);padding:10px 18px;border-radius:7px}button:hover{border-color:var(--lime);background:#20271c}a{color:inherit}button:focus-visible,a:focus-visible,textarea:focus-visible,summary:focus-visible{outline:3px solid var(--lime);outline-offset:4px}.skip{position:absolute;left:16px;top:-80px;background:var(--lime);color:#10150b;padding:12px;z-index:5}.skip:focus{top:12px}header{height:91px;display:flex;align-items:center;justify-content:space-between;padding:0 4%;border-bottom:1px solid var(--line);gap:20px}.brand{font-size:16px;letter-spacing:.08em;font-weight:800;text-decoration:none;display:flex;align-items:center;gap:12px}.mark{font-size:36px;color:var(--lime);line-height:1}.header-note{font-size:12px;letter-spacing:.16em;color:var(--muted)}.layout{display:grid;grid-template-columns:330px minmax(0,1fr);max-width:1500px;margin:auto}aside{padding:40px 28px 36px 40px;border-right:1px solid var(--line)}.eyebrow{font-size:12px;letter-spacing:.16em;font-weight:700;color:var(--lime)}h1{font-size:32px;line-height:1.13;letter-spacing:-.035em;margin:18px 0}em{font-family:Georgia,serif;font-weight:normal;color:var(--lime)}.muted{color:var(--muted)}.small{font-size:12px;color:var(--muted)}nav{display:grid;gap:5px;margin:28px 0}nav button{text-align:left;border-color:transparent;display:flex;align-items:center;gap:13px;padding:11px 12px;font-size:14px;line-height:1.35;width:100%}nav button span{font-size:12px;color:var(--muted);min-width:22px}nav button.active{background:#20281a;border-color:#3f5131;color:var(--lime)}nav button.done span{color:var(--lime)}.progress-label{font-size:12px;display:flex;justify-content:space-between;color:var(--muted)}progress{width:100%;height:5px;border:0;display:block;margin:9px 0;background:var(--line)}progress::-webkit-progress-bar{background:var(--line)}progress::-webkit-progress-value{background:var(--lime)}.audience{margin-top:30px;border-top:1px solid var(--line);padding-top:20px;font-size:14px}.audience p{color:var(--muted);margin:5px 0}main{padding:40px 6% 65px;min-width:0}.lesson-meta{display:flex;justify-content:space-between;gap:16px;align-items:center;font-size:12px;letter-spacing:.12em;color:var(--muted)}h2{font-size:clamp(35px,4.3vw,61px);line-height:1.04;letter-spacing:-.04em;margin:25px 0 22px;max-width:780px}.lead{font-size:19px;line-height:1.6;max-width:720px;color:#c1c9c2}.quote{margin:28px 0;padding:24px 28px;border-left:3px solid var(--lime);background:var(--panel);font-family:Georgia,serif;font-size:23px;line-height:1.4}.quote small{display:block;font:12px Arial,sans-serif;color:var(--muted);margin-top:12px}.section-label{font-size:12px;letter-spacing:.14em;color:var(--orange);font-weight:700}.story{border-top:1px solid var(--line);margin-top:32px;padding-top:26px}.story h3,.practice h3,.quiz h3{font-size:24px;line-height:1.3;margin:10px 0 15px;letter-spacing:-.025em}.story p{max-width:760px}.principles{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:24px 0 32px}.principle{border-top:1px solid #516044;padding-top:14px}.principle b{font-size:16px;display:block}.principle p{font-size:14px;color:var(--muted);margin:7px 0}.practice{background:#151c13;border:1px solid #37432e;padding:26px 28px;border-radius:10px;margin:30px 0}.practice label{display:block;font-size:14px;font-weight:bold;margin:20px 0 8px}textarea{width:100%;resize:vertical;min-height:108px;border:1px solid #46503f;border-radius:6px;padding:14px;background:#0c100b;color:var(--text);font:16px/1.5 Arial,sans-serif}textarea::placeholder{color:#828b7e}.save-status{min-height:24px;color:var(--muted);font-size:12px}.quiz{margin:32px 0}.answers{display:grid;gap:9px}.answers button{text-align:left;font-size:15px;padding:15px 18px}.answers button.correct{border-color:var(--lime);background:#26311c}.answers button.wrong{border-color:var(--orange)}.feedback{min-height:32px;font-size:14px;color:var(--lime);margin:12px 0}.feedback.error{color:var(--orange)}details{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:16px 0;margin:25px 0}summary{cursor:pointer;font-size:14px}details p{color:var(--muted);font-size:14px}.bottom{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-top:30px;flex-wrap:wrap}.primary{color:#17200f;background:var(--lime);border-color:var(--lime);font-weight:bold}.primary:hover{background:#e5ffad;color:#17200f}.source{font-size:12px;color:var(--muted);margin-top:36px}.finished{border:1px solid var(--lime);padding:20px;border-radius:8px;margin:24px 0}.book-layout{display:grid;grid-template-columns:210px 1fr;gap:30px;align-items:center}.book-layout img{width:100%;height:auto}.book-layout h2{font-size:36px}.book-layout p{font-size:16px}dialog{color:var(--text);background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:45px;max-width:800px;width:calc(100% - 30px)}dialog::backdrop{background:#000c}.close{position:absolute;right:10px;top:10px;font-size:22px;padding:0 10px}@media(min-width:1200px){aside{padding-left:45px}main{padding-left:65px;padding-right:65px}}@media(max-width:800px){header{height:75px;padding:0 20px}.header-note{display:none}.layout{grid-template-columns:1fr}aside{padding:25px 22px;border-right:0;border-bottom:1px solid var(--line)}aside h1{font-size:28px}aside h1 br{display:none}aside>.muted,.audience{display:none}nav{display:flex;overflow-x:auto;margin:18px 0;gap:6px;padding-bottom:5px}nav button{min-width:158px;max-width:180px}.progress-label{max-width:100%}main{padding:28px 22px 50px}h2{font-size:42px}.principles{gap:15px}.practice{padding:22px}.book-layout{grid-template-columns:1fr}.book-layout img{max-width:145px}.book-layout h2{margin-top:5px}dialog{padding:32px 24px}}@media(max-width:450px){.brand{font-size:12px;gap:8px}.mark{font-size:29px}header button{font-size:14px;padding:8px 12px}.principles{grid-template-columns:1fr}.principle{padding-top:10px}.quote{padding:20px;font-size:21px}.lesson-meta{font-size:12px;letter-spacing:.05em}h2{font-size:36px}}@media print{header,aside,.answers,.bottom,dialog{display:none}.layout{display:block}body{background:white;color:black}main{padding:0}.practice,.quote{background:white;color:black}textarea{color:black;background:white}h2{font-size:30px}}
/* Two ways to explore the same ideas. */
[hidden]{display:none!important}.header-actions{display:flex;gap:16px;align-items:center}.skin-switch{display:flex;gap:3px;padding:4px;border:1px solid var(--line);border-radius:999px}.skin-switch button{font-size:14px;padding:6px 15px;border:0;border-radius:999px}.skin-switch [aria-pressed=true]{background:var(--lime);color:#17200f;font-weight:700}.intro-nav{width:100%;margin-bottom:24px;text-align:left;font-size:14px}.intro-nav[aria-current]{border-color:var(--lime);color:var(--lime)}.aside-title{font-size:32px;line-height:1.13;letter-spacing:-.035em;font-weight:700;margin:18px 0}main h1{font-size:clamp(36px,4.1vw,60px);line-height:1.06;letter-spacing:-.045em;margin:23px 0;overflow-wrap:normal}main h2{font-size:clamp(28px,3vw,43px);line-height:1.14}.intro-hero{display:grid;grid-template-columns:1.08fr 1fr;gap:24px;align-items:center}.intro-hero h1{font-size:clamp(36px,4.05vw,59px)}.intro-lead{font-size:19px;color:#c1c9c2;line-height:1.65}.hero-actions{display:flex;align-items:flex-start;flex-direction:column;gap:12px;margin-top:26px}.hero-actions span{font-size:12px;color:var(--muted)}.hero-art{margin:0;min-width:0}.hero-art img{display:block;width:100%;height:auto;aspect-ratio:4/5;object-fit:cover;border-radius:18px}.hero-art figcaption{font-size:12px;color:var(--muted);margin-top:12px;line-height:1.5}.intro-story{padding-top:35px;margin-top:42px;border-top:1px solid var(--line)}.story-columns{display:grid;grid-template-columns:1fr 1fr;gap:28px}.story-columns p{margin:5px 0;color:#c1c9c2}.story-columns strong{color:var(--text)}.intro-manifesto{margin:38px 0;display:flex;align-items:center;gap:24px;background:#182013;border:1px solid #39492a;border-radius:12px;padding:24px}.manifesto-number{font-size:14px;font-weight:bold;letter-spacing:.08em;color:var(--lime)}.intro-manifesto p{font-size:22px;line-height:1.45;margin:0}.intro-map{margin:40px 0}.idea-steps{list-style:none;padding:0;display:grid;grid-template-columns:1fr 1fr;gap:25px 28px}.idea-steps li{display:flex;gap:16px;padding:20px 0;border-top:1px solid var(--line)}.idea-steps li:last-child{grid-column:1/-1;max-width:650px}.idea-steps li>span{width:36px;height:36px;flex-shrink:0;border-radius:50%;display:grid;place-items:center;font-size:14px;color:var(--lime);background:#222c19}.idea-steps h3{margin:0 0 8px;font-size:20px;line-height:1.35}.idea-steps p{margin:0;color:var(--muted);font-size:16px}.together{display:grid;grid-template-columns:1.1fr 1fr;gap:28px;align-items:center;border-top:1px solid var(--line);padding-top:36px}.together img{width:100%;height:auto;border-radius:16px}.together img.intro-cover{max-width:240px;justify-self:center;box-shadow:0 15px 45px #0008}.together p{color:var(--muted)}.lesson-opening{display:grid;grid-template-columns:1.4fr 1fr;gap:24px;align-items:center}.lesson-art{margin:20px 0}.lesson-art img{width:100%;height:auto;aspect-ratio:1;object-fit:cover;border-radius:16px}.lesson-art figcaption{font-size:12px;color:var(--muted);line-height:1.5;margin-top:8px}button:disabled{opacity:.5;cursor:default}.skin-switch button:hover{background:#26321b}.skin-switch [aria-pressed=true]:hover{background:var(--lime)}
/* Youth skin: ink-blue type, saturated chapter colours and playful paper panels. */
html[data-skin=ragazzi]{color-scheme:light;--bg:#f4f7ff;--panel:#fff;--text:#17234d;--muted:#536080;--line:#cbd6ed;--lime:#4433bb;--orange:#b23a0a;font-family:'Trebuchet MS',Arial,sans-serif}
[data-skin=ragazzi] body{background:#f4f7ff}
[data-skin=ragazzi] header{background:#fff;border-bottom:2px solid #17234d}
[data-skin=ragazzi] .brand{color:#17234d;letter-spacing:.045em}
[data-skin=ragazzi] .mark{color:#5a38d3}
[data-skin=ragazzi] .skin-switch{border:2px solid #17234d;background:#f0efff}
[data-skin=ragazzi] .skin-switch button{color:#17234d}
[data-skin=ragazzi] .skin-switch button[aria-pressed=true]{color:white;background:#5136cb}
[data-skin=ragazzi] .skin-switch button:hover{background:#ded8ff}
[data-skin=ragazzi] .skin-switch button[aria-pressed=true]:hover{background:#3f28ab}
[data-skin=ragazzi] aside{background:#eaf0ff;border-right:2px solid #d1daf0}
[data-skin=ragazzi] .aside-title{font-weight:900}
[data-skin=ragazzi] em{font-family:inherit;font-style:normal;font-weight:900;color:#5635ca}
[data-skin=ragazzi] main h1,[data-skin=ragazzi] main h2{font-weight:900;letter-spacing:-.045em}
[data-skin=ragazzi] .primary{background:#ffd84d;border:2px solid #17234d;color:#17234d;border-radius:12px;box-shadow:4px 4px 0 #17234d;font-weight:800;transition:transform .15s,box-shadow .15s}
[data-skin=ragazzi] .primary:hover{background:#ffe77f;transform:translate(2px,2px);box-shadow:2px 2px 0 #17234d}
[data-skin=ragazzi] .intro-nav{background:#fff;border:2px solid #17234d;border-radius:12px;box-shadow:3px 3px 0 #17234d}
[data-skin=ragazzi] .intro-nav[aria-current]{background:#ffd84d;color:#17234d}
[data-skin=ragazzi] nav button{background:#fff8;border:1px solid #d1daf0;border-radius:11px;font-weight:700}
[data-skin=ragazzi] nav button:hover{background:#fff;border-color:#5136cb}
[data-skin=ragazzi] nav button.active{background:#5136cb;border-color:#5136cb;color:#fff;box-shadow:3px 3px 0 #17234d}
[data-skin=ragazzi] nav button.active span{color:white}
[data-skin=ragazzi] nav button span{font-weight:900;background:#e3dcff;color:#4433a6;width:27px;height:27px;border-radius:50%;display:grid;place-items:center}
[data-skin=ragazzi] nav button:nth-child(3n+2) span{background:#ffe086;color:#6b4700}
[data-skin=ragazzi] nav button:nth-child(3n+3) span{background:#a9eee5;color:#07554e}
[data-skin=ragazzi] nav button.active span{background:#ffffff30;color:white}
[data-skin=ragazzi] nav button.done:not(.active) span{background:#b6eee1;color:#174e3d}
[data-skin=ragazzi] .hero-art img{border:2px solid #17234d;box-shadow:7px 7px 0 #b4a7f5;border-radius:24px;transform:rotate(2deg)}
[data-skin=ragazzi] .hero-art figcaption{margin-top:20px}
[data-skin=ragazzi] .intro-lead,[data-skin=ragazzi] .lead,[data-skin=ragazzi] .story-columns p{color:#455373}
[data-skin=ragazzi] .intro-manifesto{background:#ffd84d;border:2px solid #17234d;box-shadow:5px 5px 0 #17234d;border-radius:14px}
[data-skin=ragazzi] .manifesto-number{color:#17234d}
[data-skin=ragazzi] .idea-steps li{border:2px solid #17234d;padding:23px;border-radius:16px;background:#e6dfff;box-shadow:4px 4px 0 #17234d}
[data-skin=ragazzi] .idea-steps li:nth-child(2){background:#fff0aa}
[data-skin=ragazzi] .idea-steps li:nth-child(3){background:#c5f2eb}
[data-skin=ragazzi] .idea-steps li:nth-child(4){background:#ffdbd5}
[data-skin=ragazzi] .idea-steps li:nth-child(5){background:#d9eaff;max-width:none}
[data-skin=ragazzi] .idea-steps p{color:#394966}
[data-skin=ragazzi] .idea-steps li>span{background:#17234d;color:#fff}
[data-skin=ragazzi] .lesson-art img{border:2px solid #17234d;box-shadow:5px 5px 0 #ffcc70;border-radius:20px}
[data-skin=ragazzi] .quote{background:#e6dfff;border:0;border-radius:18px;font-family:inherit;font-size:22px;font-weight:700;position:relative}
[data-skin=ragazzi] .principle{border-top:4px solid #7654d9}
[data-skin=ragazzi] .principle:nth-child(2){border-color:#ec9236}
[data-skin=ragazzi] .principle:nth-child(3){border-color:#2ba494}
[data-skin=ragazzi] .practice{background:#d2f4ed;border:2px solid #17234d;border-radius:18px;box-shadow:6px 6px 0 #a6dccf}
[data-skin=ragazzi] textarea{background:#fff;color:#17234d;border:1px solid #778ea3;border-radius:12px}
[data-skin=ragazzi] textarea::placeholder{color:#68748c}
[data-skin=ragazzi] .answers button{background:#fff;border:2px solid #c3cce2;border-radius:12px;color:#17234d}
[data-skin=ragazzi] .answers button:hover{background:#f0ecff;border-color:#674bcb}
[data-skin=ragazzi] .answers button.correct{border-color:#17775b;background:#d2f4e5}
[data-skin=ragazzi] .answers button.wrong{border-color:#aa4616;background:#fff0df}
[data-skin=ragazzi] .feedback{color:#155b46}
[data-skin=ragazzi] .feedback.error{color:#9a3611}
[data-skin=ragazzi] button:hover{background:#e8e1ff}
[data-skin=ragazzi] dialog{background:#f4f7ff;border:2px solid #17234d}
[data-skin=ragazzi] .finished{background:#fff0aa;border:2px solid #17234d}
[data-skin=ragazzi] .audience{border-color:#c0cce9}
[data-skin=ragazzi] .together>img:not(.intro-cover){border:2px solid #17234d;box-shadow:6px 6px 0 #8cced4}
@media(min-width:1450px){.layout{max-width:1600px;grid-template-columns:330px minmax(0,1fr)}.intro-hero h1{font-size:62px}}
@media(max-width:1150px) and (min-width:801px){.layout{grid-template-columns:270px minmax(0,1fr)}aside{padding:28px 20px}main{padding:32px}.intro-hero{grid-template-columns:1fr}.hero-art{max-width:580px}.hero-art img{aspect-ratio:3/2;max-height:330px}.lesson-opening{grid-template-columns:1fr}.lesson-art{max-width:400px}.lesson-art img{aspect-ratio:3/2}.story-columns{grid-template-columns:1fr;gap:10px}.idea-steps{grid-template-columns:1fr}.together{grid-template-columns:1fr}.together>img{max-width:450px}.intro-hero h1 br{display:none}}
@media(max-width:800px){header{height:auto;min-height:80px;flex-wrap:wrap;padding:14px 22px;gap:12px}.header-actions{gap:10px}.skin-switch button{padding:6px 12px}.layout{display:flex;flex-direction:column}aside{padding:16px 22px;border-bottom:1px solid var(--line)}.aside-title,aside>.eyebrow{display:none}.intro-nav{width:auto;margin:0 0 5px;padding:7px 13px}.intro-hero{grid-template-columns:1.05fr 1fr;gap:20px}.intro-hero h1{font-size:39px}.hero-art img{aspect-ratio:4/5}.intro-lead{font-size:17px}.intro-story{margin-top:32px}.story-columns{grid-template-columns:1fr;gap:14px}.lesson-opening{grid-template-columns:1.3fr 1fr}.lesson-opening h1{font-size:37px}.lesson-opening .lead{font-size:17px}.idea-steps{gap:18px}.together{gap:22px}.aside-title br{display:none}nav{margin:12px 0}.layout aside>.small{margin-bottom:0}[data-skin=ragazzi] aside{border-right:0}.hero-actions{margin-top:20px}.hero-actions button{font-size:14px}}
@media(max-width:560px){header{justify-content:center}.header-actions{justify-content:space-between;width:100%;gap:12px}.brand{font-size:15px}.skin-switch{flex:1}.skin-switch button{flex:1;font-size:14px}.intro-hero,.lesson-opening,.together{grid-template-columns:1fr}.intro-hero h1{font-size:43px;line-height:1.08}.hero-art{margin:10px 3px 0 0}.hero-art img{aspect-ratio:3/2;transform:none!important}.hero-art figcaption{margin-top:12px!important}.hero-actions button{font-size:16px}.lesson-art{max-width:none;margin:0 5px 10px 0}.lesson-art img{aspect-ratio:16/9}.intro-story h2,main h2{font-size:30px}.intro-manifesto{gap:15px;padding:20px 16px}.intro-manifesto p{font-size:19px}.manifesto-number{font-size:12px}.idea-steps{grid-template-columns:1fr}.idea-steps li{padding:20px!important}.together img{margin-top:12px}.lesson-opening h1{font-size:38px}.intro-lead{font-size:18px}.hero-actions{margin-bottom:5px}.intro-nav{font-size:13px}aside{padding-top:14px}.skin-switch button:hover{background:transparent}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
@media print{.hero-art,.lesson-art,.together img,.intro-nav,.hero-actions{display:none}.intro-hero,.story-columns,.together,.lesson-opening{display:block}html[data-skin] body{background:#fff;color:#000}.intro-manifesto,.idea-steps li{box-shadow:none!important}}