.htw-page{--htw-line:#cbd5df;--htw-soft:#eaf0fb;--htw-green:#26745c}.htw-page .shell{max-width:1320px}.htw-page [hidden]{display:none!important}.htw-page h1{font-size:clamp(2.35rem,5.7vw,5rem);line-height:1.06;letter-spacing:-.045em;max-width:1050px;margin-bottom:22px}.htw-page h2{font-size:clamp(1.6rem,3vw,2.5rem);line-height:1.15;letter-spacing:-.025em}.htw-page h3{line-height:1.25}.htw-page .site-header .header-note{letter-spacing:.08em}.htw-page .site-header nav a{text-transform:none;letter-spacing:0;font-size:14px}.htw-page .header-inner{height:auto;min-height:82px;flex-wrap:wrap;padding-block:16px}.htw-page .site-header nav{margin-left:auto;flex-wrap:wrap}.htw-kicker{text-transform:uppercase;letter-spacing:.12em;color:var(--blue);font-weight:700;font-size:.78rem;margin-bottom:15px}.htw-hero{padding-block:55px 32px}.htw-lead{font-size:1.2rem;max-width:840px;line-height:1.65}.htw-breadcrumb{font-size:.875rem;color:var(--muted);margin-bottom:25px;display:flex;flex-wrap:wrap;gap:8px}.htw-paths{display:flex;gap:9px;flex-wrap:wrap;margin:28px 0}.htw-paths a,.htw-domain-nav a{padding:10px 16px;min-height:44px;border:1px solid var(--htw-line);background:#fff;border-radius:999px;text-decoration:none;font-weight:700;font-size:.9rem}.htw-paths a[aria-current=page]{background:var(--blue);border-color:var(--blue);color:#fff}.htw-domain-nav{display:flex;flex-wrap:wrap;gap:9px;margin-top:20px}.htw-library{padding-bottom:48px}.htw-domain{padding-top:38px;border-top:1px solid var(--htw-line);margin-top:30px;scroll-margin-top:20px}.htw-domain-head{display:flex;align-items:baseline;justify-content:space-between;gap:20px}.htw-domain-head>p{max-width:470px;color:var(--muted)}.htw-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.htw-card{background:#fff;border:1px solid var(--htw-line);border-radius:14px;overflow:hidden;display:flex;flex-direction:column;transition:transform .15s,box-shadow .15s}.htw-card:hover{transform:translateY(-3px);box-shadow:0 12px 28px #19304410}.htw-card .htw-thumb{background:#f7f9fd;border-bottom:1px solid var(--htw-line);padding:12px}.htw-thumb svg{width:100%;height:auto;display:block}.htw-card-copy{padding:22px;display:flex;flex-direction:column;flex:1}.htw-card-copy h3{font-size:1.25rem;letter-spacing:-.025em}.htw-card-copy p{font-size:.9375rem;color:var(--muted)}.htw-card-copy a{margin-top:auto;font-weight:700;color:var(--blue);min-height:44px;display:flex;align-items:center;gap:8px}.htw-rhythm{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin:24px 0 10px;padding:24px 0;border-block:1px solid var(--htw-line)}.htw-rhythm strong{display:block;font-size:1rem}.htw-rhythm span{font-size:.875rem;color:var(--muted)}.htw-grade-line{display:flex;align-items:center;flex-wrap:wrap;gap:12px;margin-top:20px}.htw-grade-line label{font-size:.9rem;font-weight:700}.htw-page select{font:inherit;border:1px solid #99a9bf;border-radius:6px;padding:10px 34px 10px 12px;background:#fff;color:var(--ink);min-height:44px;max-width:100%}.htw-page button{font:inherit;cursor:pointer}.htw-page button:focus-visible,.htw-page select:focus-visible,.htw-page input:focus-visible{outline:3px solid var(--coral);outline-offset:3px}.htw-btn{border:1px solid var(--blue);background:#fff;color:var(--blue);border-radius:7px;padding:10px 16px;min-height:44px;font-weight:700}.htw-btn.primary{background:var(--blue);color:#fff}.htw-btn:disabled{opacity:.45;cursor:default}.htw-body-copy{max-width:900px;font-size:1.1rem;line-height:1.7}.htw-focus{font-size:.9rem;color:var(--htw-green);margin-top:12px}.htw-section{padding-block:38px;border-top:1px solid var(--htw-line)}.htw-lab{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(285px,.8fr);gap:35px;align-items:start}.htw-figure{margin:0;background:#fbfbf7;border:1px solid var(--htw-line);border-radius:14px;overflow:hidden}.htw-figure svg{display:block;width:100%;height:auto}.htw-figure figcaption{font-size:.9rem;line-height:1.6;padding:16px 20px;border-top:1px solid var(--htw-line);background:#fff;margin:0}.htw-explore-figure{border-radius:18px}.htw-steps{display:flex;gap:8px;flex-wrap:wrap;margin:15px 0}.htw-steps button{width:45px;height:45px;border:1px solid #9caec5;background:#fff;border-radius:50%;font-weight:700;color:var(--blue)}.htw-steps button[aria-pressed=true]{background:var(--blue);color:#fff;border-color:var(--blue)}.htw-step-text{min-height:75px;max-width:500px}.htw-controls{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:15px;margin:20px 0}.htw-controls label{display:block;font-size:.875rem;font-weight:700}.htw-controls label span{display:block;margin-bottom:5px}.htw-controls select{width:100%}.htw-outcomes{padding-left:20px}.htw-outcomes li{margin-bottom:10px}.htw-compare{display:grid;grid-template-columns:1fr 1fr;gap:22px}.htw-compare .htw-figure{background:#fff}.htw-practice{background:#fff;border:1px solid var(--htw-line);border-radius:16px;overflow:hidden}.htw-practice-tabs{display:flex;flex-wrap:wrap;gap:0;border-bottom:1px solid var(--htw-line);background:#f7f9fd}.htw-practice-tabs button{flex:1 1 130px;border:0;border-bottom:3px solid transparent;background:transparent;padding:14px 12px;min-height:52px;color:var(--muted);font-weight:700}.htw-practice-tabs button[aria-pressed=true]{border-bottom-color:var(--blue);color:var(--blue);background:#fff}.htw-practice-content{display:grid;grid-template-columns:minmax(0,.95fr) minmax(0,1.05fr);gap:28px;padding:26px}.htw-practice-content .htw-figure{align-self:start}.htw-question h3{font-size:1.3rem;line-height:1.45}.htw-choices{border:0;padding:0;margin:18px 0}.htw-choices legend{font-size:.875rem;color:var(--muted);padding-bottom:10px}.htw-choices label{display:flex;gap:10px;align-items:flex-start;border:1px solid #b9c6d8;border-radius:7px;padding:12px;margin-bottom:9px;cursor:pointer;min-height:48px}.htw-choices label:has(input:checked){background:#edf2ff;border-color:var(--blue)}.htw-choices input{flex:none;width:18px;height:18px;accent-color:var(--blue);margin:3px 0 0}.htw-actions{display:flex;flex-wrap:wrap;gap:10px}.htw-feedback{font-weight:700;min-height:27px;margin-top:16px;color:var(--blue)}.htw-hint{padding:12px 15px;border-left:3px solid var(--blue);background:#edf2ff}.htw-page details{border-top:1px solid var(--htw-line);padding-block:13px;margin-top:12px}.htw-page summary{cursor:pointer;min-height:44px;display:list-item;font-weight:700;color:var(--blue);padding-block:8px}.htw-worked p{padding-top:8px}.htw-assumptions{max-width:920px}.htw-status{font-size:.9rem;color:var(--muted)}.htw-footnotes{max-width:940px}.htw-footnotes li{margin-bottom:10px}.htw-page .site-footer{margin-top:30px}.htw-page .footer-inner{flex-wrap:wrap;gap:20px}.htw-page .footer-links{flex-wrap:wrap}.htw-page .footer-links a{min-height:44px}.htw-static-check{padding-block:20px;border-top:1px solid var(--htw-line)}.htw-static-check li{padding:3px 0}.htw-values{width:100%;border-collapse:collapse;margin-block:16px;font-size:.9rem}.htw-values caption{text-align:left;font-weight:700;margin-bottom:8px}.htw-values th,.htw-values td{text-align:left;border-bottom:1px solid var(--htw-line);padding:8px}.htw-back-next{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}.htw-back-next a{min-height:44px;display:flex;align-items:center;color:var(--blue);font-weight:700}.htw-root-entry{margin:28px 0;padding:26px;background:#eaf0fb;border:1px solid #bacbe7;border-radius:12px}.htw-root-entry h3{font-size:1.7rem;margin-bottom:10px}.htw-root-entry p{max-width:750px}.htw-root-entry a{display:inline-block;margin-top:7px;padding:10px 16px;min-height:44px;background:var(--blue);color:#fff;border-radius:5px;font-weight:700;text-decoration:none}.htw-overview-links{display:flex;gap:12px;flex-wrap:wrap;margin-block:20px}.htw-overview-links a{display:inline-flex;align-items:center;min-height:44px;padding:10px 14px;background:#fff;border:1px solid var(--htw-line);border-radius:6px;font-weight:700;text-decoration:none;color:var(--blue)}
@media(max-width:960px){.htw-lab{grid-template-columns:1fr 1fr;gap:24px}.htw-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.htw-page .header-note{display:none}.htw-page .shell{width:calc(100% - 44px)}.htw-practice-content{grid-template-columns:1fr}.htw-practice-content .htw-figure{max-width:650px;width:100%;margin-inline:auto}}
@media(max-width:640px){.htw-page .shell{width:calc(100% - 28px)}.htw-page .header-inner{gap:14px}.htw-page .site-header nav{gap:14px;margin-left:0;justify-content:flex-start}.htw-hero{padding-block:30px 24px}.htw-lead{font-size:1.05rem}.htw-rhythm{grid-template-columns:1fr 1fr}.htw-grid,.htw-lab,.htw-compare{grid-template-columns:1fr}.htw-domain-head{display:block}.htw-domain-head>p{margin-top:-8px}.htw-section{padding-block:28px}.htw-step-text{min-height:0}.htw-practice-content{padding:16px;gap:23px}.htw-practice-tabs button{flex-basis:50%;font-size:.875rem}.htw-controls{gap:10px}.htw-controls:has(label:only-child){grid-template-columns:1fr}.htw-page .htw-breadcrumb{font-size:.8rem}.htw-card-copy{padding:20px}.htw-figure figcaption{padding:13px 15px}.htw-body-copy{font-size:1rem}.htw-page .brand{font-size:12px}.htw-back-next{display:block}.htw-root-entry{padding:20px}}
@media(prefers-reduced-motion:reduce){.htw-page *{scroll-behavior:auto!important;transition:none!important}.htw-card:hover{transform:none}}

.htw-page .site-header nav{display:flex}

/* Expanded subject library: reading routes and local topic discovery. */
.htw-library-stats{display:flex;flex-wrap:wrap;gap:18px 36px;margin:28px 0;color:var(--muted);font-size:.9rem}.htw-library-stats strong{font-size:1.6rem;letter-spacing:-.04em;color:var(--blue);margin-right:5px}.htw-domain-count{display:inline-block;font-size:.8rem;font-weight:500;letter-spacing:0;color:var(--muted);margin-left:10px;white-space:nowrap}.htw-trail-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:25px}.htw-trail-grid article{padding:24px;background:#eaf0fb;border:1px solid #becfe6;border-radius:12px}.htw-trail-grid h3{font-size:1.35rem;margin:0 0 10px}.htw-trail-grid p{font-size:.95rem;max-width:45ch}.htw-trail-grid ol{padding-left:23px;margin-bottom:0}.htw-trail-grid li{padding:7px 0 7px 4px}.htw-trail-grid a{font-weight:700;color:var(--blue);text-underline-offset:3px}.htw-trail-grid small{display:block;font-size:.75rem;color:var(--muted);margin-top:3px}.htw-browse{padding-bottom:5px}.htw-browse-controls{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(0,1fr) auto;gap:18px;align-items:end;margin-top:24px}.htw-browse-controls label{display:flex;flex-direction:column;gap:7px;font-size:.9rem;font-weight:700}.htw-browse-controls input{font:inherit;min-height:46px;width:100%;min-width:0;border:1px solid #99a9bf;border-radius:6px;padding:10px 12px;background:#fff;color:var(--ink)}.htw-browse-controls input:focus-visible{outline:3px solid var(--coral);outline-offset:3px}.htw-browse-controls .htw-btn{min-height:46px}.htw-next-ideas{padding-block:20px 30px}.htw-next-ideas h2{font-size:1.7rem}.htw-next-ideas ul{padding-left:20px}.htw-next-ideas li{padding:8px 0}.htw-next-ideas a{font-weight:700;color:var(--blue)}.htw-next-ideas span{display:block;font-size:.8rem;color:var(--muted);margin-top:3px}
@media(max-width:700px){.htw-trail-grid{grid-template-columns:1fr}.htw-trail-grid article{padding:20px}.htw-browse-controls{grid-template-columns:1fr 1fr;gap:14px}.htw-browse-controls label:first-child{grid-column:1/-1}.htw-browse-controls .htw-btn{width:100%}.htw-library-stats{gap:12px 22px}.htw-domain-count{font-size:.75rem}}
.htw-card-copy .htw-card-band{display:inline-block;align-self:flex-start;font-size:.75rem;line-height:1.4;color:#2349bd;background:#eaf0fb;border-radius:4px;padding:4px 8px;margin:0 0 12px;font-weight:700}.htw-card-copy [data-topic-preview]{min-height:3em}
.htw-collection-note{background:#eaf0fb;border-left:4px solid var(--blue);padding:18px 22px;margin-top:22px;max-width:950px}.htw-collection-note h2{font-size:1.3rem;margin:0 0 10px}.htw-collection-note p{margin:8px 0;max-width:80ch}.htw-prerequisites{font-size:.92rem;max-width:850px;background:#edf3ee;border-left:3px solid #26745c;padding:13px 16px;margin-top:20px}
.htw-journey-card{border-top:4px solid var(--htw-green)}.htw-journey-card .htw-kicker{color:var(--htw-green)}.htw-journey-card .htw-status{font-size:.8rem;line-height:1.6}.htw-journey-stages{list-style:none;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:22px;margin:26px 0}.htw-journey-stages>li{background:#fff;border:1px solid var(--htw-line);border-radius:12px;padding:25px;display:flex;flex-direction:column}.htw-journey-stages h3{font-size:1.35rem}.htw-journey-stages h3 a{color:var(--ink);text-underline-offset:4px}.htw-connecting-question{border-left:3px solid var(--htw-green);padding-left:13px;color:#235c4b}.htw-journey-lesson{margin-top:auto;padding-top:12px;color:var(--blue);font-weight:700;min-height:44px}.htw-transfer-case{padding-block:28px;border-top:1px solid var(--htw-line)}.htw-transfer-case>.htw-lab{grid-template-columns:minmax(0,1fr) minmax(0,1fr);margin-top:20px}.htw-transfer-case .htw-figure{align-self:start}.htw-transfer-case [data-controls][hidden]+[data-static]{display:block}.htw-lesson-journeys{padding-block:20px}.htw-lesson-journeys h2{font-size:1.7rem}.htw-lesson-journeys a{font-weight:700;color:var(--blue)}.htw-journey-return{display:inline-flex;align-items:center;text-decoration:none;margin-top:20px}
@media(max-width:760px){.htw-journey-stages,.htw-transfer-case>.htw-lab{grid-template-columns:1fr}.htw-journey-stages>li{padding:20px}}

/* Reading first: one continuous column, with the illustration in the exposition. */
.htw-page .htw-reading{max-width:840px;padding-block:42px 54px}.htw-reading-header h1{font-size:clamp(2rem,4.6vw,3.7rem);line-height:1.12;margin:0 0 32px;max-width:100%;letter-spacing:-.035em}.htw-reading-header .htw-kicker{font-size:.78rem;margin-bottom:13px}.htw-reading-prose{font-size:1.13rem;line-height:1.85;color:var(--ink)}.htw-reading-prose p{margin:0 0 24px;max-width:72ch}.htw-reading-figure{margin:30px auto;max-width:700px;background:#fff}.htw-reading-figure figcaption{font-size:.97rem;line-height:1.65;color:var(--ink);padding:17px 22px}.htw-reading-prose .htw-reading-legend{font-size:.9rem;line-height:1.6;color:var(--muted)}.htw-reading-further{margin-top:34px;font-size:.95rem;line-height:1.7}.htw-reading-further details{margin:0;padding-block:7px}.htw-reading-further summary{font-size:.95rem;color:var(--muted);font-weight:600}.htw-reading-further details[open] summary{color:var(--blue)}.htw-reading-further .htw-next-ideas{padding:0}.htw-reading-further .htw-next-ideas ul,.htw-reading-further .htw-lesson-journeys{margin:10px 0;padding:0 0 0 20px}.htw-reading-further .htw-next-ideas li{padding:4px 0}.htw-reading-further .htw-figure{margin:18px 0}.htw-reading-further #reset-scene{margin-bottom:16px}.htw-reading-back{display:inline-flex;align-items:center;min-height:44px;margin-top:30px;font-weight:700;color:var(--blue);text-underline-offset:4px}.htw-reading[data-reading-grade=k2] .htw-reading-prose{font-size:1.23rem;line-height:1.85}.htw-journey-card .htw-card-copy>p:not(.htw-kicker){display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:3;overflow:hidden}
@media(max-width:640px){.htw-page .htw-reading{padding-top:28px}.htw-reading-header h1{margin-bottom:25px}.htw-reading-prose{font-size:1.06rem;line-height:1.8}.htw-reading[data-reading-grade=k2] .htw-reading-prose{font-size:1.14rem}.htw-reading-figure{margin-block:24px}.htw-reading-figure figcaption{padding:14px 16px;font-size:.93rem}}
.htw-path-entry{margin:26px 0;padding:23px 26px;background:#edf3ee;border:1px solid #bfd1c6;border-radius:12px;max-width:950px}.htw-path-entry h2{font-size:1.35rem;margin:0 0 10px}.htw-path-entry p{max-width:72ch;margin:0 0 12px}.htw-path-entry a{display:inline-flex;align-items:center;min-height:44px;font-weight:700;color:var(--htw-green)}.htw-path-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}.htw-path-card{background:#fff;border:1px solid var(--htw-line);border-top:4px solid var(--htw-green);padding:26px;border-radius:12px}.htw-path-card h2{font-size:1.7rem}.htw-path-card>a{display:block;padding:18px 0;border-top:1px solid var(--htw-line);text-decoration:none;color:var(--blue)}.htw-path-card>a>span,.htw-path-card>a>strong,.htw-path-card>a>small{display:block}.htw-path-card>a>span{font-size:.8rem;color:var(--muted);margin-bottom:4px}.htw-path-card>a>strong{font-size:1.1rem}.htw-path-card>a>small{font-size:.85rem;color:var(--muted);margin-top:5px}.htw-path-units{max-width:950px!important}.htw-path-unit{border-top:1px solid var(--htw-line);padding:28px 0;scroll-margin-top:25px}.htw-path-unit h2{font-size:1.7rem}.htw-path-unit>p{max-width:75ch}.htw-path-unit ol{padding-left:27px}.htw-path-unit li{padding:12px 0 12px 8px;border-bottom:1px solid #dce3eb}.htw-path-unit li>a{font-weight:600;font-size:1.05rem;line-height:1.5;color:var(--ink);text-underline-offset:4px}.htw-path-unit li>span{display:block;font-size:.8rem;color:var(--muted);margin-top:5px}.htw-path-start{display:inline-flex;align-items:center;text-decoration:none;margin-top:14px}.htw-path-footer{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap;padding-block:25px 45px}.htw-path-footer>a{min-height:44px;display:inline-flex;align-items:center;font-weight:700;color:var(--blue)}.htw-reading-sequence{border-top:1px solid var(--htw-line);padding-top:22px;margin-top:30px}.htw-reading-sequence>p{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;font-size:.85rem}.htw-reading-sequence>p>a{color:var(--muted)}.htw-reading-sequence>div{display:grid;grid-template-columns:1fr 1fr;gap:18px}.htw-reading-sequence>div>a{display:block;background:#eef3fd;border:1px solid var(--htw-line);border-radius:8px;padding:16px;font-weight:600;text-decoration:none;color:var(--blue);line-height:1.5}.htw-reading-sequence>div>a>span{display:block;font-size:.8rem;font-weight:400;color:var(--muted);margin-bottom:7px}
@media(max-width:680px){.htw-path-grid{grid-template-columns:1fr}.htw-path-card{padding:21px}.htw-path-entry{padding:20px}.htw-reading-sequence>div{grid-template-columns:1fr}}

/* Wonder discovery uses the same age-curated topic collection. */
.htw-wonder-entry{margin:30px 0;padding:28px;background:#f0f4fe;border:1px solid #bdccec;border-radius:16px}.htw-wonder-entry h2{margin-bottom:12px}.htw-wonder-entry>p{max-width:780px}.htw-wonder-starts{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:22px}.htw-wonder-starts a{display:flex;flex-direction:column;gap:8px;padding:20px;background:#fff;border:1px solid #bdccec;border-radius:10px;text-decoration:none;color:var(--ink);min-height:44px}.htw-wonder-starts a:hover{border-color:var(--blue)}.htw-wonder-starts a:focus-visible{outline:3px solid var(--coral);outline-offset:3px}.htw-wonder-starts strong{color:var(--blue)}.htw-wonder-starts span{font-size:.95rem;line-height:1.6}.htw-wonder-starts small{font-size:.85rem;color:var(--blue);font-weight:700;margin-top:auto}.htw-card-copy .htw-wonder-label{color:#5c3d83;font-size:.78rem;font-weight:700;margin:0 0 10px}.htw-browse-controls{grid-template-columns:minmax(0,1.5fr) minmax(0,1fr) minmax(0,1fr) auto}.htw-browse-controls select{width:100%}
@media(max-width:850px){.htw-browse-controls{grid-template-columns:1fr 1fr}.htw-browse-controls label:first-child{grid-column:1/-1}}@media(max-width:600px){.htw-wonder-entry{padding:20px}.htw-wonder-starts{grid-template-columns:1fr}.htw-browse-controls{grid-template-columns:1fr}.htw-browse-controls label:first-child{grid-column:auto}}