:root{--paper:#eef2ed;--card:#fff;--ink:#153126;--muted:#52675d;--line:#cbd6cf;--green:#155c42;--green2:#247858;--blue:#1c5d85;--gold:#b56d08;--gold-bg:#fff3d8;--ok:#1d6b49;--ok-bg:#e2f3e9;--bad:#9a3328;--bad-bg:#fae7e3;--shadow:0 12px 32px rgba(21,49,38,.09);--radius:14px}*{box-sizing:border-box}html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.6 Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif}button,input,select,textarea{font:inherit}:where(a,button,input,select,textarea,[tabindex]):focus-visible{outline:3px solid var(--gold);outline-offset:3px}a{color:var(--green)}.unit-header{position:sticky;top:0;z-index:20;display:flex;min-height:64px;align-items:center;justify-content:space-between;gap:20px;padding:8px clamp(18px,5vw,64px);background:var(--ink);color:#fff}.wordmark{display:flex;align-items:center;gap:9px;color:#fff;font-weight:800;text-decoration:none}.wordmark 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rgba(21,49,38,.04);color:var(--ink);text-decoration:none;transition:transform .18s,box-shadow .18s,border-color .18s}.lesson-card:hover{transform:translateY(-2px);border-color:#86a998;box-shadow:var(--shadow)}.card-number{display:grid;width:44px;height:44px;place-items:center;border-radius:50%;background:#e0eee7;color:var(--green);font-weight:900}.topic{margin:0 0 3px;color:var(--gold);font-size:.78rem;font-weight:850;letter-spacing:.08em;text-transform:uppercase}.lesson-card h3{margin:0 0 7px;font:700 1.35rem/1.2 Georgia,serif}.lesson-card p:not(.topic){margin:0;color:var(--muted)}.status{align-self:center;padding:5px 9px;border-radius:999px;background:#edf1ee;color:var(--muted);font-size:.78rem;font-weight:800;white-space:nowrap}.lesson-card.complete .status{background:var(--ok-bg);color:var(--ok)}.assessment-card{border-left:5px solid var(--gold)}footer{display:flex;justify-content:space-between;gap:20px;padding:28px clamp(18px,5vw,64px);border-top:1px solid 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14px;font:700 clamp(2.6rem,6vw,5rem)/.98 Georgia,serif;letter-spacing:-.035em}.lesson-meta{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0 0}.lesson-meta span{padding:5px 9px;border-radius:6px;background:#dfeae4;color:var(--green);font-size:.82rem;font-weight:800}.objectives{margin:26px 0 0;padding:18px 22px;border-left:4px solid var(--gold);background:var(--gold-bg)}.objectives h2{margin:0 0 8px;font-size:1rem}.objectives ul{margin:0;padding-left:20px}.content-section{scroll-margin-top:86px;padding:42px 0 18px;border-bottom:1px solid var(--line)}.content-section>h2{margin:0 0 12px;font:700 clamp(1.8rem,3vw,2.4rem)/1.12 Georgia,serif}.content-section>p{max-width:78ch}.note-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin:22px 0}.note-card{padding:18px;border:1px solid var(--line);border-radius:12px;background:var(--card)}.note-card h3{margin:0 0 6px;font:700 1.1rem Georgia,serif}.note-card 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select{width:100%;min-height:42px;border:1px solid #77847d;border-radius:7px;background:#fff;color:var(--ink)}.order-list{display:grid;gap:8px;margin:0;padding:0;list-style:none}.order-item{display:grid;grid-template-columns:auto 1fr auto;gap:10px;align-items:center;padding:11px;border:1px solid var(--line);border-radius:9px;background:#fbfcfa}.order-item .handle{color:var(--muted);font-weight:900}.order-controls{display:flex;gap:5px}.order-controls button{width:38px;height:38px;border:1px solid var(--line);border-radius:7px;background:#fff;color:var(--ink);font-weight:900;cursor:pointer}.lab-controls{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.lab-controls label{font-weight:800}.lab-controls select{width:100%;min-height:44px;margin-top:5px;border:1px solid #77847d;border-radius:8px;background:#fff;color:var(--ink)}.lab-output{margin-top:18px;overflow-x:auto}.lab-output table{width:100%;border-collapse:collapse}.lab-output th,.lab-output 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3rem/1 Georgia,serif;color:#ffe3a8}@media(max-width:840px){.lesson-grid{grid-template-columns:1fr}.lesson-shell{grid-template-columns:1fr}.lesson-rail{position:static}.lesson-rail ol{display:none}.lab-controls{grid-template-columns:1fr}.unit-header nav a:first-child{display:none}}@media(max-width:600px){.lesson-card{grid-template-columns:42px 1fr}.lesson-card .status{grid-column:2}.note-grid{grid-template-columns:1fr}.select-row{grid-template-columns:1fr}.section-title{align-items:start;flex-direction:column}.unit-header{padding-inline:16px}.lesson-shell,.hub-shell{width:min(100% - 24px,1120px)}footer{flex-direction:column}.unit-intro{padding:32px 24px}.activity{padding:17px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}